Harrop intake
Safety Car
Joined: Jun 2009
Posts: 3,888
Likes: 2
From: Frederick, Maryland
Ill cover the remedies I explained earlier in this quotation. To explain some remedies, one in which you seem to be mainly concerned with is the increase of IAT's.
I was aware that our engine bay (any for this matter) is inevitably hot. Actions I have already taken to decrease this is for one, Wrapping the manifolds. It will do nothing but good. and The bay's temps will most certainly drop, and even like the factory, you could fab up heatshields as well. I cannot post IAT's of my setup to show a decrease and Im unsure if Robz has made a provision for the IAT sensor (Harrop did not) and logged data regarding IAT's.
Another action I took, one for function, another for looks is a pretty expensive purchase but well worth it.
The VIS SCV Heat extractor hood.
Now not many run this hood (as much as Ive seen, but Its hard to deny that with the front bumper I have (2Fperformance) and this vented hood that my engine bay temps could possibly remain uneffected. Sadly I havnt had time to record info (Id love to actually)
But with those two things, with out adding other ways to draw air out, I feel are enough, to justify the switch to an ITB.
Second, your post about rec. vs cath. is questionable............please post up all the records that the rec. port heads have "taken" from the cath. port heads. Because the cath. own 90% of the records.
Unless your referring to dyno queens......and in that case......I'm out.........
As I'm sure your aware of......there is way more to an induction system than max flow.......LOL.
Thanks...........and I'm only in this thread because I have a real interest in the ITB.
Unless your referring to dyno queens......and in that case......I'm out.........
As I'm sure your aware of......there is way more to an induction system than max flow.......LOL.
Thanks...........and I'm only in this thread because I have a real interest in the ITB.
This is why The C5R is ITB'd and not a shared plenum intake.
Debating Rec. vs Cath seems very opinionated and very debatable. I will just say that the C5R (Coming from the Cath. port C5) uses Rect. port heads with their ITB. I wont debate in drag racing because Im not sure, its not in my interests. But Im sure your well aware that in the C5, I believe Robz (Itb'd C5) runs holds or held the fastest NA C5. Maybe he'll join to explain his reasoning for using an ITB in drag racing and what port style heads he has (Im assuming cath.) Drag racing is out of my knowledge.
I dont mind the questions LSHOLIC.
Hopefully Ive outlined everything thoroughly. I hope this becomes helpful to many members on the fence about ITB's
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
I had to quote this specifically because it needed to be addressed. If someone (the owner) would have sleepless nights over trumpet placement then an ITB IS NOT FOR THEM. The cross ram style is a widely "accepted" placement for them. Unless you go with Borla's setup which I dislike anyway. So simply, if they immediately fear the trumpets being over their manifolds, spend the 5k+ somewhere else. Now if they can move past that and utilize some "remedies" then thats a different story.
Let me clarify.....if they radiant issue is not resolved...AKA; trumpet placement "out of the box", needs a heat sink and/or thermal barrier in place. By the way.....what are you IAT's with your ITB after driving for a couple miles ?? Real IAT's...not the air coming in down by the rad shroud.
I believe you're mistaking (or at least under the assumption) that an ITB is designed for mainly numbers and max effort builds. In my eyes it is specifically for maximum efficiency. I say that because for the simple fact that instead of sharing one plenum for 8 cyl. you are effectively treating EACH cyl as one self-contained motor, Agree? One cyl gets its own amount of fuel,air and spark, making it nearly independent from the others. Therefore its extremely efficient, and yes there is added power (because of flow). This is why you don't see ITB's are not on many drag cars (No I have'nt forgotten about Robz, I said many) because they serve a different purpose, that being throttle response and its ability to make power in high rpms.
Yes I understand the ITB concept....the real question is which wave/reflection is your trumpet length taking advantage of ?? And here is what I believe to be the truth.....written below......And I always assume this section to be a drag race majority....and my response reflects that.
"Idle quality and low speed drive ability will generally be much better with individual runners/throttles because you don't have a shared plenum chamber with a depression under a closed throttle that allows a cylinder that is filling to also pull in exhaust from another cylinder that's on overalp at the same time.
And why ITB's work so well........What Is Ram Tuning?
Ram tuning surfaced in the racing community during the early 1950s. The idea is both simple and quite complicated, depending on how deep you dig. On the surface, ram tuning simply takes advantage of the inertia contained within a moving column of air/fuel mixture as it comes to a stop against the closed intake valve. Traveling at close to 100 mph through the intake runner, you can imagine there is plenty of energy waiting to be released. By adjusting the length of the intake runners, this energy can be used to improve cylinder filling when the valve opens again. The more pent-up energy waiting to crash the gate, the more air to pack the chamber. But there's much more to it than this.
It all begins at the piston. After expelling spent combustion gases through the open exhaust valve during the exhaust stroke, the piston reaches TDC. At approximately the time the piston begins its journey back down the cylinder during the intake stroke, the intake valve opens and suction draws in a fresh air/fuel charge through the intake tract. By the time the piston reaches BDC, the intake valve is closing, and it is here that we can begin our examination of the occurrences along the length of the intake tract. For these few milliseconds, we aren't concerned about what is happening inside the cylinder or the combustion chamber. Our attention is focused on the column of air that exists between the back of the closed intake valve and the opening of the ram tube or, on a carbureted engine, the entrance to the plenum directly below the carburetor.
The instant the intake valve closes, it initiates a chain of events within that column of air. A set of four of these events will always occur in a particular order. These four events constitute a harmonic cycle. Each event involves a change in the pressure and velocity of the air/fuel mixture in the tube. These changes always begin at one end of the tube (either the closed valve or the open end) and progress to the other end. This progression, or traversal, occurs at the speed of sound; a harmonic cycle consists of four traversals.
The first traversal is the result of the fuel mixture adjacent to the valve coming to a sudden stop. As it does, it builds up a pressure which is equal to the product of the air density, the air velocity, and the sonic velocity. As the incoming molecules of air hit this pocket of air that is already stopped, they also stop, and the volume of stalled air grows in size, creating a division between the two zones; this "front" is like a weather front on the evening news. The front separates regions that are at different pressures. This front moves away from the valve and toward the open end of the tube at sonic velocity. It is the front between the two regions that traverses the tube at the speed of sound, not a portion of the air/fuel mixture itself. Each wave actually moves through the air without being of it.
When the front reaches the open end of the tube, the molecules of air nearest the open end begin to flow away from the opening of the tube. This volume of zeropressure air flowing away from the engine then extends toward the closed valve at the speed of sound, constituting the second traversal, where the air in the tube is at zero pressure and negative flow. Then, the air at the closed valve experiences a negative pressure equal in magnitude to the positive pressure initially developed when the valve first closed, thus initiating the third traversal which also travels away from the engine. Once the front reaches the end of the tube, the air inside is entirely stagnant, and at the negative pressure, air once again begins to flow into the open end of the tube. This represents the beginning of the fourth traversal, where all the air in the tube is at zero pressure and has a positive velocity traveling toward the engine.
With this fourth traversal, one harmonic cycle is completed, although it's difficult to imagine all of this taking place in the short timespan between valve closure and valve opening. The beginning of the first cycle of the next harmonic occurs when this flow region reaches the closed valve, and, again the pressure rise is equal to the product of the density of the charge, the velocity of the charge, and the speed of sound, which - at 60 degrees F - is equal to 13,420 inches per second! Shope divulged that tests conducted at Chrysler in the mid-'50s concluded that the most effective time to open the valve was after the third harmonic - the intake valve is opened just as the pressure rise begins to occur at the valve head after the 12th traversal. These experiments also showed that when tuning for the fourth harmonic, the intake runner had to be too short and couldn't contain enough air/fuel mixture to completely charge the cylinder. And efforts to tune for the second harmonic resuited in extremely long runners and the acceleration of an excessive air/fuel mass, so the third harmonic was the most advantageous.
Chrysler testing resulted in a formula to calculate where the ram effect will come into play. To wit: N x L = 84,000, where N represents the desired engine rpm to tune for and L is the length in inches from the opening of the ram tube to the valve head. Shope explains: "Let's say you're running at Bonneville with an engine that develops peak horsepower at 8,400 rpm and want to tune for maximum ram effect at that level. Then, L should equal 10 inches, as in 8,400x10 inches = 84,000." To achieve ram tuning at 5,500 rpm, simply divide the constant, 84,000 by 5,500 rpm. The result of 84,000-5,500 = 15.27, the ideal distance for the intake tract as measured from the opening of the ram tube to the valve head.
The effects of ram tuning reveal themselves as blips in the horsepower and torque curves which can either be tailored (by manipulating runner length) to coincide with, and enhance, the power peak or to bolster some other area of the power curve. In other words, just because a given engine may make maximum horsepower at 7,000 rpm doesn't mean you have to utilize the benefit of ram tuning at that speed. In fact, in most cases, you wouldn't. A drag-race engine, for instance, would have its intake system tuned for a speed a bit above the midpoint of the engine-speed range. Is ram tuning responsible for where peak torque and horsepower are made? Well, it can shift the peaks a few rpm, but the more dominant contributors are found elsewhere (camshaft, compression ratio, and so on). But there is no doubt ram tuning can be a useful tool for enhancing the power curves."~per EMAP-USA
I suggested how another Harrop owner has K&N filters on each trumpet, so that will filter the air for normal driving (Not tracking). I will add that I believe Robz uses covers when driving here and there, and takes them off at the track.
Ill cover the remedies I explained earlier in this quotation. To explain some remedies, one in which you seem to be mainly concerned with is the increase of IAT's.
I was aware that our engine bay (any for this matter) is inevitably hot. Actions I have already taken to decrease this is for one, Wrapping the manifolds. It will do nothing but good. and The bay's temps will most certainly drop, and even like the factory, you could fab up heatshields as well. I cannot post IAT's of my setup to show a decrease and Im unsure if Robz has made a provision for the IAT sensor (Harrop did not) and logged data regarding IAT's.
Another action I took, one for function, another for looks is a pretty expensive purchase but well worth it.
A insulated air pan like this which would encompass the complete ITB trumpets, with the air pan being feed by a cold air system from the front of the car...and would enter at the front of the air pan, which is sealed to the bottom of the hood. Which would be filtered in route (like the Vararam) as to not "dirty" the air at the trumpet entrance.
The VIS SCV Heat extractor hood.
Now not many run this hood (as much as Ive seen, but Its hard to deny that with the front bumper I have (2Fperformance) and this vented hood that my engine bay temps could possibly remain uneffected. Sadly I havnt had time to record info (Id love to actually)
But with those two things, with out adding other ways to draw air out, I feel are enough, to justify the switch to an ITB.
I'm unfamiliar with your hood but if the "opening" is beyond the "midway" point on the hood it will have a deteriorating effect on cooling at speed. The C5 wind tunnel test show a high pressure area from about midway on the hood all the way to, half way up the windshield. Look at the C5R hood....the ducting is midway to forward placement on the hood. Your looking for a negative pressure to "equalize" the under hood high pressure. Bernoulli principle....
If your hood is exiting in the rear...its high pressure...so how is the high pressure under the hood going to exit/or be "pulled" out ??
By records I assume you mean only drag racing. Id rather not spend time in searching for ITB members drag racing because honestly I dont know many, which I stated earlier.Its centralized in road coursing.
And I always assume this section to be a drag race majority....and my response reflects that.
This is why The C5R is ITB'd and not a shared plenum intake.
Debating Rec. vs Cath seems very opinionated and very debatable. I will just say that the C5R (Coming from the Cath. port C5) uses Rect. port heads with their ITB. I wont debate in drag racing because Im not sure, its not in my interests. But Im sure your well aware that in the C5, I believe Robz (Itb'd C5) runs holds or held the fastest NA C5. Maybe he'll join to explain his reasoning for using an ITB in drag racing and what port style heads he has (Im assuming cath.) Drag racing is out of my knowledge.
Here is some good reading for ya.....and if its not "deep" enough, we can get into coefficient of discharge and curtain areas. But I will sum up the article....MAST Motorsports provided their top cathedral and rectangle heads for a comparison. As well as custom cams for both heads....and cross check the cams in the "other" head. Summary......despite the rec. have higher "flow" numbers, they "peaked" only 1-2 hp higher than the cath. heads. But the cath. heads provided almost an additional 20 lb-ft below 4000rpm.
http://www.gmhightechperformance.com...ead/index.html
I dont mind the questions LSHOLIC.
Hopefully Ive outlined everything thoroughly. I hope this becomes helpful to many members on the fence about ITB's
Let me clarify.....if they radiant issue is not resolved...AKA; trumpet placement "out of the box", needs a heat sink and/or thermal barrier in place. By the way.....what are you IAT's with your ITB after driving for a couple miles ?? Real IAT's...not the air coming in down by the rad shroud.
I believe you're mistaking (or at least under the assumption) that an ITB is designed for mainly numbers and max effort builds. In my eyes it is specifically for maximum efficiency. I say that because for the simple fact that instead of sharing one plenum for 8 cyl. you are effectively treating EACH cyl as one self-contained motor, Agree? One cyl gets its own amount of fuel,air and spark, making it nearly independent from the others. Therefore its extremely efficient, and yes there is added power (because of flow). This is why you don't see ITB's are not on many drag cars (No I have'nt forgotten about Robz, I said many) because they serve a different purpose, that being throttle response and its ability to make power in high rpms.
Yes I understand the ITB concept....the real question is which wave/reflection is your trumpet length taking advantage of ?? And here is what I believe to be the truth.....written below......And I always assume this section to be a drag race majority....and my response reflects that.
"Idle quality and low speed drive ability will generally be much better with individual runners/throttles because you don't have a shared plenum chamber with a depression under a closed throttle that allows a cylinder that is filling to also pull in exhaust from another cylinder that's on overalp at the same time.
And why ITB's work so well........What Is Ram Tuning?
Ram tuning surfaced in the racing community during the early 1950s. The idea is both simple and quite complicated, depending on how deep you dig. On the surface, ram tuning simply takes advantage of the inertia contained within a moving column of air/fuel mixture as it comes to a stop against the closed intake valve. Traveling at close to 100 mph through the intake runner, you can imagine there is plenty of energy waiting to be released. By adjusting the length of the intake runners, this energy can be used to improve cylinder filling when the valve opens again. The more pent-up energy waiting to crash the gate, the more air to pack the chamber. But there's much more to it than this.
It all begins at the piston. After expelling spent combustion gases through the open exhaust valve during the exhaust stroke, the piston reaches TDC. At approximately the time the piston begins its journey back down the cylinder during the intake stroke, the intake valve opens and suction draws in a fresh air/fuel charge through the intake tract. By the time the piston reaches BDC, the intake valve is closing, and it is here that we can begin our examination of the occurrences along the length of the intake tract. For these few milliseconds, we aren't concerned about what is happening inside the cylinder or the combustion chamber. Our attention is focused on the column of air that exists between the back of the closed intake valve and the opening of the ram tube or, on a carbureted engine, the entrance to the plenum directly below the carburetor.
The instant the intake valve closes, it initiates a chain of events within that column of air. A set of four of these events will always occur in a particular order. These four events constitute a harmonic cycle. Each event involves a change in the pressure and velocity of the air/fuel mixture in the tube. These changes always begin at one end of the tube (either the closed valve or the open end) and progress to the other end. This progression, or traversal, occurs at the speed of sound; a harmonic cycle consists of four traversals.
The first traversal is the result of the fuel mixture adjacent to the valve coming to a sudden stop. As it does, it builds up a pressure which is equal to the product of the air density, the air velocity, and the sonic velocity. As the incoming molecules of air hit this pocket of air that is already stopped, they also stop, and the volume of stalled air grows in size, creating a division between the two zones; this "front" is like a weather front on the evening news. The front separates regions that are at different pressures. This front moves away from the valve and toward the open end of the tube at sonic velocity. It is the front between the two regions that traverses the tube at the speed of sound, not a portion of the air/fuel mixture itself. Each wave actually moves through the air without being of it.
When the front reaches the open end of the tube, the molecules of air nearest the open end begin to flow away from the opening of the tube. This volume of zeropressure air flowing away from the engine then extends toward the closed valve at the speed of sound, constituting the second traversal, where the air in the tube is at zero pressure and negative flow. Then, the air at the closed valve experiences a negative pressure equal in magnitude to the positive pressure initially developed when the valve first closed, thus initiating the third traversal which also travels away from the engine. Once the front reaches the end of the tube, the air inside is entirely stagnant, and at the negative pressure, air once again begins to flow into the open end of the tube. This represents the beginning of the fourth traversal, where all the air in the tube is at zero pressure and has a positive velocity traveling toward the engine.
With this fourth traversal, one harmonic cycle is completed, although it's difficult to imagine all of this taking place in the short timespan between valve closure and valve opening. The beginning of the first cycle of the next harmonic occurs when this flow region reaches the closed valve, and, again the pressure rise is equal to the product of the density of the charge, the velocity of the charge, and the speed of sound, which - at 60 degrees F - is equal to 13,420 inches per second! Shope divulged that tests conducted at Chrysler in the mid-'50s concluded that the most effective time to open the valve was after the third harmonic - the intake valve is opened just as the pressure rise begins to occur at the valve head after the 12th traversal. These experiments also showed that when tuning for the fourth harmonic, the intake runner had to be too short and couldn't contain enough air/fuel mixture to completely charge the cylinder. And efforts to tune for the second harmonic resuited in extremely long runners and the acceleration of an excessive air/fuel mass, so the third harmonic was the most advantageous.
Chrysler testing resulted in a formula to calculate where the ram effect will come into play. To wit: N x L = 84,000, where N represents the desired engine rpm to tune for and L is the length in inches from the opening of the ram tube to the valve head. Shope explains: "Let's say you're running at Bonneville with an engine that develops peak horsepower at 8,400 rpm and want to tune for maximum ram effect at that level. Then, L should equal 10 inches, as in 8,400x10 inches = 84,000." To achieve ram tuning at 5,500 rpm, simply divide the constant, 84,000 by 5,500 rpm. The result of 84,000-5,500 = 15.27, the ideal distance for the intake tract as measured from the opening of the ram tube to the valve head.
The effects of ram tuning reveal themselves as blips in the horsepower and torque curves which can either be tailored (by manipulating runner length) to coincide with, and enhance, the power peak or to bolster some other area of the power curve. In other words, just because a given engine may make maximum horsepower at 7,000 rpm doesn't mean you have to utilize the benefit of ram tuning at that speed. In fact, in most cases, you wouldn't. A drag-race engine, for instance, would have its intake system tuned for a speed a bit above the midpoint of the engine-speed range. Is ram tuning responsible for where peak torque and horsepower are made? Well, it can shift the peaks a few rpm, but the more dominant contributors are found elsewhere (camshaft, compression ratio, and so on). But there is no doubt ram tuning can be a useful tool for enhancing the power curves."~per EMAP-USA
I suggested how another Harrop owner has K&N filters on each trumpet, so that will filter the air for normal driving (Not tracking). I will add that I believe Robz uses covers when driving here and there, and takes them off at the track.
Ill cover the remedies I explained earlier in this quotation. To explain some remedies, one in which you seem to be mainly concerned with is the increase of IAT's.
I was aware that our engine bay (any for this matter) is inevitably hot. Actions I have already taken to decrease this is for one, Wrapping the manifolds. It will do nothing but good. and The bay's temps will most certainly drop, and even like the factory, you could fab up heatshields as well. I cannot post IAT's of my setup to show a decrease and Im unsure if Robz has made a provision for the IAT sensor (Harrop did not) and logged data regarding IAT's.
Another action I took, one for function, another for looks is a pretty expensive purchase but well worth it.
A insulated air pan like this which would encompass the complete ITB trumpets, with the air pan being feed by a cold air system from the front of the car...and would enter at the front of the air pan, which is sealed to the bottom of the hood. Which would be filtered in route (like the Vararam) as to not "dirty" the air at the trumpet entrance.
The VIS SCV Heat extractor hood.
Now not many run this hood (as much as Ive seen, but Its hard to deny that with the front bumper I have (2Fperformance) and this vented hood that my engine bay temps could possibly remain uneffected. Sadly I havnt had time to record info (Id love to actually)
But with those two things, with out adding other ways to draw air out, I feel are enough, to justify the switch to an ITB.
I'm unfamiliar with your hood but if the "opening" is beyond the "midway" point on the hood it will have a deteriorating effect on cooling at speed. The C5 wind tunnel test show a high pressure area from about midway on the hood all the way to, half way up the windshield. Look at the C5R hood....the ducting is midway to forward placement on the hood. Your looking for a negative pressure to "equalize" the under hood high pressure. Bernoulli principle....
If your hood is exiting in the rear...its high pressure...so how is the high pressure under the hood going to exit/or be "pulled" out ??By records I assume you mean only drag racing. Id rather not spend time in searching for ITB members drag racing because honestly I dont know many, which I stated earlier.Its centralized in road coursing.
And I always assume this section to be a drag race majority....and my response reflects that.
This is why The C5R is ITB'd and not a shared plenum intake.
Debating Rec. vs Cath seems very opinionated and very debatable. I will just say that the C5R (Coming from the Cath. port C5) uses Rect. port heads with their ITB. I wont debate in drag racing because Im not sure, its not in my interests. But Im sure your well aware that in the C5, I believe Robz (Itb'd C5) runs holds or held the fastest NA C5. Maybe he'll join to explain his reasoning for using an ITB in drag racing and what port style heads he has (Im assuming cath.) Drag racing is out of my knowledge.
Here is some good reading for ya.....and if its not "deep" enough, we can get into coefficient of discharge and curtain areas. But I will sum up the article....MAST Motorsports provided their top cathedral and rectangle heads for a comparison. As well as custom cams for both heads....and cross check the cams in the "other" head. Summary......despite the rec. have higher "flow" numbers, they "peaked" only 1-2 hp higher than the cath. heads. But the cath. heads provided almost an additional 20 lb-ft below 4000rpm.
http://www.gmhightechperformance.com...ead/index.html
I dont mind the questions LSHOLIC.
Hopefully Ive outlined everything thoroughly. I hope this becomes helpful to many members on the fence about ITB's
AMP Racing
Joined: Aug 2006
Posts: 10,754
Likes: 589
From: Washington TWP NJ
2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
It seems to me the base of the windshield is considered a high pressure area.
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
It seems to me the base of the windshield is considered a high pressure area.
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
Thanks.............and I saw you dirty old man post !!!!! I laughed out loud !!!!
Last edited by LSOHOLIC; Jul 28, 2012 at 07:55 PM.
Safety Car
Joined: Jun 2009
Posts: 3,888
Likes: 2
From: Frederick, Maryland
I can't beleive you copy/ pasted all that 
lol
The issues you keep describing are in the design, and thats nothing I can control lol. If your unhappy with the design of the ITB not having a sealed and filtered enclosure, protected from heat, then I guess your best bet is to mock up something. With all what your saying idk if an ITB is what you even want. The closest thing your describing is the C5R/C6R ITB. otherwise Kinsler, harrop, twm and Jenvey, all are nothing of what your looking for by the sounds of it, especially if you want it out of the box. Again, your talking about drag racing, ok I understand, but the high pressure build up your referring to is at pretty high speeds (170-200)
Many road racers are at the tracks doing 150, no problem. I never said my hood would elimiminate the pressure build up. I just said how it was vented and most likely reduce heat. Im sure the hood would reduce temps on the street and road course use. But if your concerned with trapping 170 in the 1/4 (being NA of course) and the pressure building up, and not being able vent the heat lol Im sure I'd have your same worries. I'm sure you could work some meth into the equation.
Long story short, idk what to tell you. Your argument is over design that should be corrected "out of the box" .....probably not gonna happen for a realistic amount, even then 5k+ for an NA add on is a stretch.
Capt that would be nice, one hood that comes to mind that could possibly be made functional is Rk sports ram air hood.
The issues stated above IMO is in the design, and if someone is not willing to modify, or adjust accordingly to remedy the "cons" then it's not meant to be.
I think I've made it clear from a street/ road race and drag that it makes for a great intake, outflows the fasts, and doesn't die out up high. I believe robz's makes power to about 9k rpm.
lolThe issues you keep describing are in the design, and thats nothing I can control lol. If your unhappy with the design of the ITB not having a sealed and filtered enclosure, protected from heat, then I guess your best bet is to mock up something. With all what your saying idk if an ITB is what you even want. The closest thing your describing is the C5R/C6R ITB. otherwise Kinsler, harrop, twm and Jenvey, all are nothing of what your looking for by the sounds of it, especially if you want it out of the box. Again, your talking about drag racing, ok I understand, but the high pressure build up your referring to is at pretty high speeds (170-200)
Many road racers are at the tracks doing 150, no problem. I never said my hood would elimiminate the pressure build up. I just said how it was vented and most likely reduce heat. Im sure the hood would reduce temps on the street and road course use. But if your concerned with trapping 170 in the 1/4 (being NA of course) and the pressure building up, and not being able vent the heat lol Im sure I'd have your same worries. I'm sure you could work some meth into the equation.
Long story short, idk what to tell you. Your argument is over design that should be corrected "out of the box" .....probably not gonna happen for a realistic amount, even then 5k+ for an NA add on is a stretch.
It seems to me the base of the windshield is considered a high pressure area.
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
if you made a pan similar to the one pictured above but one on each side surrounding the trumpets and fed air from the back of the hood, it could work pretty good.
You wouldn't be able to use a stock hood though...
Interesting discussion, nonetheless...
The issues stated above IMO is in the design, and if someone is not willing to modify, or adjust accordingly to remedy the "cons" then it's not meant to be.
I think I've made it clear from a street/ road race and drag that it makes for a great intake, outflows the fasts, and doesn't die out up high. I believe robz's makes power to about 9k rpm.
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
I can't beleive you copy/ pasted all that lol
The issues you keep describing are in the design, and thats nothing I can control lol. If your unhappy with the design of the ITB not having a sealed and filtered enclosure, protected from heat, then I guess your best bet is to mock up something. With all what your saying idk if an ITB is what you even want. The closest thing your describing is the C5R/C6R ITB. otherwise Kinsler, harrop, twm and Jenvey, all are nothing of what your looking for by the sounds of it, especially if you want it out of the box. Again, your talking about drag racing, ok I understand, but the high pressure build up your referring to is at pretty high speeds (170-200)
Many road racers are at the tracks doing 150, no problem. I never said my hood would elimiminate the pressure build up. I just said how it was vented and most likely reduce heat. Im sure the hood would reduce temps on the street and road course use. But if your concerned with trapping 170 in the 1/4 (being NA of course) and the pressure building up, and not being able vent the heat lol Im sure I'd have your same worries. I'm sure you could work some meth into the equation.
Long story short, idk what to tell you. Your argument is over design that should be corrected "out of the box" .....probably not gonna happen for a realistic amount, even then 5k+ for an NA add on is a stretch.
Capt that would be nice, one hood that comes to mind that could possibly be made functional is Rk sports ram air hood.
The issues stated above IMO is in the design, and if someone is not willing to modify, or adjust accordingly to remedy the "cons" then it's not meant to be.
I think I've made it clear from a street/ road race and drag that it makes for a great intake, outflows the fasts, and doesn't die out up high. I believe robz's makes power to about 9k rpm.
lolThe issues you keep describing are in the design, and thats nothing I can control lol. If your unhappy with the design of the ITB not having a sealed and filtered enclosure, protected from heat, then I guess your best bet is to mock up something. With all what your saying idk if an ITB is what you even want. The closest thing your describing is the C5R/C6R ITB. otherwise Kinsler, harrop, twm and Jenvey, all are nothing of what your looking for by the sounds of it, especially if you want it out of the box. Again, your talking about drag racing, ok I understand, but the high pressure build up your referring to is at pretty high speeds (170-200)
Many road racers are at the tracks doing 150, no problem. I never said my hood would elimiminate the pressure build up. I just said how it was vented and most likely reduce heat. Im sure the hood would reduce temps on the street and road course use. But if your concerned with trapping 170 in the 1/4 (being NA of course) and the pressure building up, and not being able vent the heat lol Im sure I'd have your same worries. I'm sure you could work some meth into the equation.
Long story short, idk what to tell you. Your argument is over design that should be corrected "out of the box" .....probably not gonna happen for a realistic amount, even then 5k+ for an NA add on is a stretch.
Capt that would be nice, one hood that comes to mind that could possibly be made functional is Rk sports ram air hood.
The issues stated above IMO is in the design, and if someone is not willing to modify, or adjust accordingly to remedy the "cons" then it's not meant to be.
I think I've made it clear from a street/ road race and drag that it makes for a great intake, outflows the fasts, and doesn't die out up high. I believe robz's makes power to about 9k rpm.
Do you have any track data to back up what Harrop is "selling" you ?? In reference to your cars build and intentions ??
And what are some of the details of your build that warrant an ITB ??
And fyi, none of this is meant to come across condescending of rude.....but when we start talking tech/facts....I tend to be of a passionate nature.
Thanks..........and pasting only takes 4 key strokes...really simple procedure.
Safety Car
Joined: Jun 2009
Posts: 3,888
Likes: 2
From: Frederick, Maryland
On the contrary....if your willing to live with Harrop's the short comings in a "street" car, then it sounds like its the manifold for you.........
Do you have any track data to back up what Harrop is "selling" you ?? In reference to your cars build and intentions ??
And what are some of the details of your build that warrant an ITB ??
And fyi, none of this is meant to come across condescending of rude.....but when we start talking tech/facts....I tend to be of a passionate nature.
Thanks..........and pasting only takes 4 key strokes...really simple procedure.
Do you have any track data to back up what Harrop is "selling" you ?? In reference to your cars build and intentions ??
And what are some of the details of your build that warrant an ITB ??
And fyi, none of this is meant to come across condescending of rude.....but when we start talking tech/facts....I tend to be of a passionate nature.
Thanks..........and pasting only takes 4 key strokes...really simple procedure.
Either way lets get back on track....
I feel for NA people yes the ITB is the single greatest thing I put on my car. I don't understand though why you say what Harrop is "selling" me? I'm no rep for them but I have driven the car with it and have experience with this intake.mwhat you see above is my personal intake being polished. The Harrop was kind of love at first sight. As soon as I saw it I wanted it. So I spent weeks and weeks researching ITB's, different brands. Talking to robz even. And I knew it was something I wanted to experience.
At the time of purchase I had two things done to my car
Dynatech lung tube system
M12 Transmission
Those two things, my 120k mile car dyno'ed
355hp and 365tq. and the torque was at idle hahahahah
The throttle response was so vicious, gently taking off from a stop light was really hard to do
I don't think I can convey it to you though to where you'll understand the benefit or experience.
I'm in the process of having a low mile ls1, ms3, prc heads,UD, and 4.10 gears put in my car. This is a temp build till I decide what to do with this twin turbo kit I have lol
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
Not rude, but combative yes lol especially at the end. I know how to C/P, but I won't do 8 paragraphs for the sake of the Convo lol see my point?
Either way lets get back on track....
I feel for NA people yes the ITB is the single greatest thing I put on my car. I don't understand though why you say what Harrop is "selling" me? I'm no rep for them but I have driven the car with it and have experience with this intake.mwhat you see above is my personal intake being polished. The Harrop was kind of love at first sight. As soon as I saw it I wanted it. So I spent weeks and weeks researching ITB's, different brands. Talking to robz even. And I knew it was something I wanted to experience.
At the time of purchase I had two things done to my car
Dynatech lung tube system
M12 Transmission
Those two things, my 120k mile car dyno'ed
355hp and 365tq. and the torque was at idle hahahahah
The throttle response was so vicious, gently taking off from a stop light was really hard to do
I don't think I can convey it to you though to where you'll understand the benefit or experience.
I'm in the process of having a low mile ls1, ms3, prc heads,UD, and 4.10 gears put in my car. This is a temp build till I decide what to do with this twin turbo kit I have lol
Either way lets get back on track....
I feel for NA people yes the ITB is the single greatest thing I put on my car. I don't understand though why you say what Harrop is "selling" me? I'm no rep for them but I have driven the car with it and have experience with this intake.mwhat you see above is my personal intake being polished. The Harrop was kind of love at first sight. As soon as I saw it I wanted it. So I spent weeks and weeks researching ITB's, different brands. Talking to robz even. And I knew it was something I wanted to experience.
At the time of purchase I had two things done to my car
Dynatech lung tube system
M12 Transmission
Those two things, my 120k mile car dyno'ed
355hp and 365tq. and the torque was at idle hahahahah
The throttle response was so vicious, gently taking off from a stop light was really hard to do
I don't think I can convey it to you though to where you'll understand the benefit or experience.
I'm in the process of having a low mile ls1, ms3, prc heads,UD, and 4.10 gears put in my car. This is a temp build till I decide what to do with this twin turbo kit I have lol
And we disagree on so many levels.....we will leave it at that. Did I hear you correct...4.10's in a turbo car ?? PRC's ??........OK, your build and $$'s.
Good luck with your project.....
Thanks...........btw, what are your goals and design of the car ??
.
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Safety Car
Joined: Jun 2009
Posts: 3,888
Likes: 2
From: Frederick, Maryland
Ok...TriplBlk, I posted the info for everyone. Not just you, I would assume if you own a Harrop that you would understand the benefits. So the copy and past was for the benefit of the "thread".
And we disagree on so many levels.....we will leave it at that. Did I hear you correct...4.10's in a turbo car ?? PRC's ??........OK, your build and $$'s.
Good luck with your project.....
Thanks...........btw, what are your goals and design of the car ??
.
And we disagree on so many levels.....we will leave it at that. Did I hear you correct...4.10's in a turbo car ?? PRC's ??........OK, your build and $$'s.
Good luck with your project.....
Thanks...........btw, what are your goals and design of the car ??
.
Idk how we disagree, we're just not on the same page. You keeping thinking about things that I can't see purposeful aka the extreme worry for IAT's when that can be remedied. Venting a hood. Just because my hood does it one way, doesn't mean ACP's is bad for instance (wind tunnel tested)
It must be getting late because your really starting to jump the gun on things lol. I stated the parts I had prc head btw, and said it was a temp. Build. I still have my old rear. Yes an M12 with 4.10's and boost would be...ridiculous lol
And for goals, it's hard to say. Right now I just want to enjoy my car to its greatest ability, that IS something we both can agree on
Op sry for being the focal point of the thread, just wanted to inform. Hope you find what you want
Last edited by TriplBlk; Jul 28, 2012 at 09:23 PM.
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
No cliff notes? Lol
Idk how we disagree, we're just not on the same page. You keeping thinking about things that I can't see purposeful aka the extreme worry for IAT's when that can be remedied. Venting a hood. Just because my hood does it one way, doesn't mean ACP's is bad for instance (wind tunnel tested)
It must be getting late because your really starting to jump the gun on things lol. I stated the parts I had prc head btw, and said it was a temp. Build. I still have my old rear. Yes an M12 with 4.10's and boost would be...ridiculous lol
And for goals, it's hard to say. Right now I just want to enjoy my car to its greatest ability, that IS something we both can agree on
Op sry for being the focal point of the thread, just wanted to inform. Hope you find what you want
Idk how we disagree, we're just not on the same page. You keeping thinking about things that I can't see purposeful aka the extreme worry for IAT's when that can be remedied. Venting a hood. Just because my hood does it one way, doesn't mean ACP's is bad for instance (wind tunnel tested)
It must be getting late because your really starting to jump the gun on things lol. I stated the parts I had prc head btw, and said it was a temp. Build. I still have my old rear. Yes an M12 with 4.10's and boost would be...ridiculous lol
And for goals, it's hard to say. Right now I just want to enjoy my car to its greatest ability, that IS something we both can agree on
Op sry for being the focal point of the thread, just wanted to inform. Hope you find what you want
Your willing to spend $5G's on a manifold then put PRC's on it......I really do not understand the logic....
...You effectively moved the bottle neck from the manifold to the head....How is your manifold suppose to be a "badazz" if the heads wont move the air....its a system.......and its the sum of its parts.Ported by Ray Charles heads are digitized from whos work ?? Exactly !!
I'm not trying to be crappy.....I really dont see your system. Similar to the Harrop in a mild street car build......
Yeah, if you setting records or in a class where hundredths separate a 16 car field...then sure. And a shelf cam..........like I said your car your $$$$.And yes we can agree you just want to enjoy your car to its greatest ability.
Good luck with your build.
Thanks.....I'm really a super nice guy.........LOL.....this is reflecting badly on me.....
(being opinionated on someone else's build)
Le Mans Master
Joined: Mar 1999
Posts: 6,029
Likes: 84
From: Palm Coast, FL
I recall there were a lot of issues getting a corvette computer to not shut the gas flow off after 8k (or something close to that number) ... RobZ had to work pretty hard to get a computer to see and willing to provide fuel @ 9K ... The 600 rpm idle is what impresses me the most
interesting post!
interesting post!
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
LSOHOLIC TriplBlk
We buried the hatchet PM style......
Sorry to the OP.....the harrop is a wayyyyyyyyyyyy awesome intake....but to me its a last bridge to cross, after all I's have been dotted and T's crossed. I mean chit Robz went 9.98 w/sbe 346" with a Fast manifold.
Thanks..............
TriplBlkWe buried the hatchet PM style......
Sorry to the OP.....the harrop is a wayyyyyyyyyyyy awesome intake....but to me its a last bridge to cross, after all I's have been dotted and T's crossed. I mean chit Robz went 9.98 w/sbe 346" with a Fast manifold.
Thanks..............
Safety Car
Joined: Jun 2009
Posts: 3,888
Likes: 2
From: Frederick, Maryland
I recall there were a lot of issues getting a corvette computer to not shut the gas flow off after 8k (or something close to that number) ... RobZ had to work pretty hard to get a computer to see and willing to provide fuel @ 9K ... The 600 rpm idle is what impresses me the most
interesting post!
interesting post!
LSOHOLIC TriplBlk
We buried the hatchet PM style......
Sorry to the OP.....the harrop is a wayyyyyyyyyyyy awesome intake....but to me its a last bridge to cross, after all I's have been dotted and T's crossed. I mean chit Robz went 9.98 w/sbe 346" with a Fast manifold.
Thanks..............
TriplBlkWe buried the hatchet PM style......
Sorry to the OP.....the harrop is a wayyyyyyyyyyyy awesome intake....but to me its a last bridge to cross, after all I's have been dotted and T's crossed. I mean chit Robz went 9.98 w/sbe 346" with a Fast manifold.
Thanks..............
And yea I didn't know that, I know he added the harrop and went 9.6 with the same ls6?
I'd love details on the build. Seems hush hush lol
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
Thanks.............and I could be wrong....but I am a student of history.....
.........and a student of the game.
Last edited by LSOHOLIC; Jul 30, 2012 at 10:49 PM.
Thread Starter
Dig
Joined: Jan 2006
Posts: 5,460
Likes: 1,125
From: Port Saint Lucie FLORIDA & HONDURAS
Interesting on both sides.
The intake is a "pull that last drop of hp" from your ride. This can be on a simple street build or something as mad as my 416" motor. In any case, if someone wants to spend 5K on an intake thats up to them even if they have under 400 rwhp. The Harrop styles is gorgeous and the throttle response making the cake. Tuning.... that's just part of the game we play getting our combo's working to the best they can.
I'm still waiting on a response from robz (PM'd a while back) regarding some questions we all want (need) to know.
Let's just face it... if the Harrop was only $690.00 we would all find a way to make things work.
The intake is a "pull that last drop of hp" from your ride. This can be on a simple street build or something as mad as my 416" motor. In any case, if someone wants to spend 5K on an intake thats up to them even if they have under 400 rwhp. The Harrop styles is gorgeous and the throttle response making the cake. Tuning.... that's just part of the game we play getting our combo's working to the best they can.
I'm still waiting on a response from robz (PM'd a while back) regarding some questions we all want (need) to know.
Let's just face it... if the Harrop was only $690.00 we would all find a way to make things work.
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
Interesting on both sides.
The intake is a "pull that last drop of hp" from your ride. This can be on a simple street build or something as mad as my 416" motor. In any case, if someone wants to spend 5K on an intake thats up to them even if they have under 400 rwhp. The Harrop styles is gorgeous and the throttle response making the cake. Tuning.... that's just part of the game we play getting our combo's working to the best they can.
I'm still waiting on a response from robz (PM'd a while back) regarding some questions we all want (need) to know.
Let's just face it... if the Harrop was only $690.00 we would all find a way to make things work.
The intake is a "pull that last drop of hp" from your ride. This can be on a simple street build or something as mad as my 416" motor. In any case, if someone wants to spend 5K on an intake thats up to them even if they have under 400 rwhp. The Harrop styles is gorgeous and the throttle response making the cake. Tuning.... that's just part of the game we play getting our combo's working to the best they can.
I'm still waiting on a response from robz (PM'd a while back) regarding some questions we all want (need) to know.
Let's just face it... if the Harrop was only $690.00 we would all find a way to make things work.
I look at it like this.............if you feel that you have extracted every bit of power (under the curve) and can USE the extra air and rpm the manifold provides then.......yes it may be for you. I would ask you this.......where is your current manifold falling short ?? I could only guess that your valve events are based on the conventional LS style manifold....meaning switching the manifold only would yield a "small" return....useless other parameters of your combo were changes to capitalize on the ITB setup.
Also, do you have the ability to tune it your self or do you have a local tuner that can tackle this manifold ?? Or are you going to drag it across the country for the "specialized" tuner to work the bugs out ?? IMO, a manifold like this is not a 1 dyno session kind of tune or drive it for half a day tune...........its more of a everyday tweak kind of manifold....until every parameter of the manifold is "touched". May take weeks to get it perfect.....and perfect is the only way that manifold "pays for its self".
I also feel 80% of the vette guys make more than plenty of rwhp to run the number their after.....most of the time people are so "ate up" with making more power that they forget its a system. Many people over look the "other" critical items on the car. Clutch/convertor, proper trans ratios, vehicle static weight, vehicle rotational weight (inertia), wheel package, tires, shocks and the most important item.................................... ........................................ ........................................ ..seat time...AKA; driver mod !!
Here is some good reading for ya.........this was a conversation between a buddy of mine and Monte aboout getting down the track with his current power....He (buddy) felt he should be going faster (f-body guy).
I would NOT limit the front end to 1" of travel. Let the front have plenty of travel, just control it with the shocks. That is what shocks are for, is to "control" the front end. No shock can work well, with no range to operate. Also remember, when a car hits the limiter, it is DONE transferring weight, at that point. You have stopped the pitch rotation, dead in its tracks. Where as, you let the front extend, but do it "slowly", with shock control, the transfer happens over a much greater amount of time and is smooth. You effectively want the car to be carrying the wheels, with the shocks still dropping out of the wheelwell slowly. Look at your pics.........the car has the fronts way in the air, is barely off the line and the front is at full droop. Slow this down and you will be faster. Most radial cars, with decent power...I shoot for full droop at 1 sec out. We are about 1.3 on Pro-Mod stuff
I can explain, why it does both those things.
The goal of the rear shock, is to control the rear end housing. The car is always trying to do two things to the rear end......one, is to line up the pinion and two, throw the housing out from under the car. The shocks job is to control this and help apply those forces to the chassis. The first reaction, of ANY rear suspension, is to seperate, what it does after that, depends on the type suspension, anti-squat percenatge and so on. But first, it wants to seperate. So if you have the rear extension, very loose, it just hammers the rear tire and throws the housing at the ground rapidly. If the compression is loose, is basically trys to "bounce" the housing and you can get shake as you describe.........but it does not shake because you loosened the compression, it shakes because the extension is so loose, the shocks can't control the housing. The tight compression, is a crutch, that happens to help the issue. If the extension was tighter and the housing more under control, the compression would be better able to do its job, which is to control the rebound of the housing and also let the car absorb bumps in the track. Unless your shocks are worn, I would imagine bumps upset it, or it is very stiff in the rear, with the shocks set on "full tight".
In addition, to very loose, rear extension settings, you also have a loose front, so you have two things, pounding the tire into the pavement. Obviously the goal of the front shock, is to control the rate of front end rise and weight transfer. While you may think you are low on power, you do have a bit of torque, with the hose on. Torque is what accelerates a car forward, but with your car so loose, it is basically fighting itself on each end of the car. Try to focus your power on moving the car forward, instead of making it "pitch rotate" so rapidly.
All this going on, is one reason the car seems to 60ft decent, but is slow to 330. It is just crushing the tire, for the amount of power you have. It needs to be smoother and apply the power smoother. People focus way too much on 60ft numbers. 330 numbers are what counts. We all know, you have to dead hook a radial...........but, do you think it will be faster to 330, with the sidewall "stood up" or "crushed".
One last thing, you are about to change your launch procedure, from basically having the converter maxxed out and THEN the nitrous comes on, to now leaving ON the hose and letting the converter get a run at the motor. Just one more thing, that is going to hammer the tire.
The tighter you can run your settings on extension, the faster the car will be............that is a proven fact
Just a few things to think about.~per Monte Smith
Good luck with your project 123sugey
Thanks.........granted its about a f-body...and does not translate 100%....but you get the idea. IMO, just start thinking about the "rest" of the car.
.
Last edited by LSOHOLIC; Jul 29, 2012 at 03:56 PM.
Thread Starter
Dig
Joined: Jan 2006
Posts: 5,460
Likes: 1,125
From: Port Saint Lucie FLORIDA & HONDURAS
Good read.
I'm installing drag shocks (all 4 corners) that I purchased from robz a while back. Will be tweaking everything once up in NJ in November with "the guys".
I have the hp and the drivers mod is being worked on. Swapped out the 3:42's and now dealing with a new animal with the 4:10's.
Any input is a great thing !!
I'm installing drag shocks (all 4 corners) that I purchased from robz a while back. Will be tweaking everything once up in NJ in November with "the guys".
I have the hp and the drivers mod is being worked on. Swapped out the 3:42's and now dealing with a new animal with the 4:10's.
Any input is a great thing !!
