FIRST Intake Arrived; Looking It Over
01-24-2018, 05:05 PM
#42
Race Director
I'm confused. If the primary benefits of the tri-y is the increased air velocity and decreased reversion at low to mid RPMs (increased low to mid RPM torque) and the fuel economy improvement that results, then why the discussion on high RPMs?
If you're saying that a TRI-Y designed for 8,500 RPM wouldn't help a street engine at normal RPMs and driving conditions, then I agree completely; that would be dumb. But a TRI-Y designed for 6,000 RPM vs. a 4:1 designed for 6,000 RPM, the TRI-Y is going to see more low and mid RPM torque and they'll have the SAME HP at the peak. That's what you want in a street motor- a broad torque peak and people like me want the fuel economy, too.
Adam
If you're saying that a TRI-Y designed for 8,500 RPM wouldn't help a street engine at normal RPMs and driving conditions, then I agree completely; that would be dumb. But a TRI-Y designed for 6,000 RPM vs. a 4:1 designed for 6,000 RPM, the TRI-Y is going to see more low and mid RPM torque and they'll have the SAME HP at the peak. That's what you want in a street motor- a broad torque peak and people like me want the fuel economy, too.
Adam
At 25% throttle do you think either will make a difference? What about 50%? Or 75%?
My point was that unless your at 100% throttle...a lot, will either design make a difference?
01-24-2018, 05:14 PM
#43
Melting Slicks
Thread Starter
My guess would be "yes". If a tri-y design increases exhaust velocity and reduces reversion, then it will make a difference at part throttle where reversion is the biggest problem.
-It is very common for people to report a small increase in highway fuel economy moving to Tri-Y / 4:2:1 headers- highway cruising is done at low throttle openings. Where's the mpg coming from??? -Increased scavenging and the associated increased VE at those RPMs and throttle openings (MOHR TORX!!!).
I can ask that very pointed question on SecTalk and see if Calvin Elston or some of the other engine super nerds will chime in on it. I'd LOVE to know the answer to this one.
My Tri-Y's-are-better "Proof": TRIY + YourEngine == MOHR AVG TORX --> MOHR AVG TORX+ Your Car == Your Butt Going MOHR FASTER. --> Going MOHR FASTER is Better, hence TRIY IS BETTER!! *The Defense Rests, Your Honor!*
Adam
Last edited by NewbVetteGuy; 01-24-2018 at 05:35 PM.
01-24-2018, 05:33 PM
#44
Le Mans Master
The best doesn't sell. The best marketing and bragging rights and big HP #'s at mostly unused RPMs sells. (You think people buy soft metal Comp Cams sewing machine cams and rebranded springs of questionable origin because they're "Best"?!? You think people buy tiny, tinny Chinese paper cone Bose speakers because they're "best"?!?)
The market largely defines "best" as highest HP at max RPM; the SBC market adds "at the cheapest price" to that demand, so that's what you see in the marketplace.
HP #'s at max RPM sell; ft lbs at low to moderate RPMs doesn't (but should); the aftermarket and especially the historical SBC aftermarket shows people often making TERRIBLE trade-offs to get bragging rights for max HP at the cost of useable, streetable torque.
"An engine is just an airpump; make everything bigger and you'll go faster" -is far too prevalent an opinion. A blunt instrument philosophy for blunt instruments. -The market is asking for the wrong thing, so the market is full of the wrong product for most street motors, IMO.
Ton of motors out there with oversized cams, oversized heads, and oversized headers with lazy bottom ends.
Too many people underthinking it for far too long.
The LS market has a lot more Tri-Ys in lot more diameters and lengths available and the good ones show good gains.
Adam
The market largely defines "best" as highest HP at max RPM; the SBC market adds "at the cheapest price" to that demand, so that's what you see in the marketplace.
HP #'s at max RPM sell; ft lbs at low to moderate RPMs doesn't (but should); the aftermarket and especially the historical SBC aftermarket shows people often making TERRIBLE trade-offs to get bragging rights for max HP at the cost of useable, streetable torque.
"An engine is just an airpump; make everything bigger and you'll go faster" -is far too prevalent an opinion. A blunt instrument philosophy for blunt instruments. -The market is asking for the wrong thing, so the market is full of the wrong product for most street motors, IMO.
Ton of motors out there with oversized cams, oversized heads, and oversized headers with lazy bottom ends.
Too many people underthinking it for far too long.
The LS market has a lot more Tri-Ys in lot more diameters and lengths available and the good ones show good gains.
Adam
Look at the fastest cars. The winners. Tell me how many are using tri Y headers. I bet you won’t find a single one.
Yes, while there is pressure to but cheap by many, the best does sell.
I paid $1,000 for my headers to have the best. I could have done far cheaper, but they wouldn’t be as good, and no way would they have the quality I expect.
I’m not saying you haven’t found good theory on the benefit of a tri Y header. What I’m saying is street and drag racing, properly designed long tubes have the advantage. Not just my opinion, but this comes from the top header manufacturers as well as engine race shops, too. And they could make tri Y headers just as easy, and they would if they offered better performance.
I’ve also been active in the LS world. I don’t even think anyone has made a tri Y for a modern vette.
Last edited by AirBusPilot; 01-24-2018 at 05:35 PM.
01-24-2018, 05:53 PM
#45
Melting Slicks
Thread Starter
Go to your local drag strip.
Look at the fastest cars. The winners. Tell me how many are using tri Y headers. I bet you won’t find a single one.
Yes, while there is pressure to but cheap by many, the best does sell.
I paid $1,000 for my headers to have the best. I could have done far cheaper, but they wouldn’t be as good, and no way would they have the quality I expect.
I’m not saying you haven’t found good theory on the benefit of a tri Y header. What I’m saying is street and drag racing, properly designed long tubes have the advantage. Not just my opinion, but this comes from the top header manufacturers as well as engine race shops, too. And they could make tri Y headers just as easy, and they would if they offered better performance.
I’ve also been active in the LS world. I don’t even think anyone has made a tri Y for a modern vette.
Look at the fastest cars. The winners. Tell me how many are using tri Y headers. I bet you won’t find a single one.
Yes, while there is pressure to but cheap by many, the best does sell.
I paid $1,000 for my headers to have the best. I could have done far cheaper, but they wouldn’t be as good, and no way would they have the quality I expect.
I’m not saying you haven’t found good theory on the benefit of a tri Y header. What I’m saying is street and drag racing, properly designed long tubes have the advantage. Not just my opinion, but this comes from the top header manufacturers as well as engine race shops, too. And they could make tri Y headers just as easy, and they would if they offered better performance.
I’ve also been active in the LS world. I don’t even think anyone has made a tri Y for a modern vette.
It's weird you keep lumping street and drag together; seems like you'd want very different things between street and drag.
For C7 Vettes checkout the Pfadt RAce Engineering Tri-Ys available in 1 3/4" (up to 650HP) and 1 7/8" (>650HP).
Adam
01-24-2018, 06:13 PM
#46
Le Mans Master
Is drag racing a scenario where a broad torque curve and low and mid RPM torque makes a difference?
It's weird you keep lumping street and drag together; seems like you'd want very different things between street and drag.
For C7 Vettes checkout the Pfadt RAce Engineering Tri-Ys available in 1 3/4" (up to 650HP) and 1 7/8" (>650HP).
Adam
It's weird you keep lumping street and drag together; seems like you'd want very different things between street and drag.
For C7 Vettes checkout the Pfadt RAce Engineering Tri-Ys available in 1 3/4" (up to 650HP) and 1 7/8" (>650HP).
Adam
Test your argument. Buy tri Y’s and use them. You might even get a custom set made, if you have the money $$$$.
I like your build, that TPI looks killer, best looking intake manifold I know of.
01-24-2018, 06:21 PM
#47
Race Director
Member Since: Apr 2007
Location: South Western Ontario
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Those look really nice but didn't work so well....
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
Last edited by lionelhutz; 01-24-2018 at 06:23 PM.
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AirBusPilot (01-24-2018),
NewbVetteGuy (01-24-2018)
01-24-2018, 06:27 PM
#48
Melting Slicks
Thread Starter
Just trollin at this point.
Adam
Last edited by NewbVetteGuy; 01-24-2018 at 06:28 PM.
01-24-2018, 06:34 PM
#49
Le Mans Master
Those look really nice but didn't work so well....
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
There you go, Adam. Real world results.
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NewbVetteGuy (01-24-2018)
01-24-2018, 07:05 PM
#50
Race Director
This makes no sense. Tri-Ys should be an easier fit than a standard 4:1 and "correct" tube diameter and length is dependant upon the output, at 400hp and below 1 5/8" is the right diameter and they're readily available from Stans.
From a fitament perspective TRI-Ys have the added benefit of essentially all being "step" headers so they can start at a smaller diameter near the head where the space is at a premium and then at the first "y" they step up to the next largest size but you've only got 2 tubes vying for 3 dimensional space.
Adam
From a fitament perspective TRI-Ys have the added benefit of essentially all being "step" headers so they can start at a smaller diameter near the head where the space is at a premium and then at the first "y" they step up to the next largest size but you've only got 2 tubes vying for 3 dimensional space.
Adam
Space at the head isn't actually all that problematic (minus spark plug access), it's the space about 4-6" below the port where you're interacting with the starter and idler arm on the passenger side, steering box/linkage and clutch linkage on the driver's side.
That said, I think I've gotten close to my limit of trying to converse with you. Good luck on your HP quest.
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NewbVetteGuy (01-24-2018)
01-24-2018, 07:12 PM
#51
Melting Slicks
Thread Starter
Those look really nice but didn't work so well....
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
https://www.corvetteforum.com/forums...ts-inside.html
The AR headers easily outperformed them down low.
So what's the conclusion? -Getting a really good header well-matched to your combo is far more important than the type of header?!? or something else entirely?
Adam
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AirBusPilot (01-24-2018)
01-24-2018, 10:38 PM
#53
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
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Exhaust tuning is fairly complicated and the details never seem to end. Us hobbiest's don't have the resources to optimize it normally. Many times owners are stuck very few choices due to smog testing.
Many overlook what happens when they use long tube headers and long tube intake runners they expect a large power increase and they get one but it could be very peaky. You may end up with high torque motor but in a narrow power band. I've read of a trend to unequal length header tubes to broaden the power band even though many will disagree I'm sure.
IMHO don't make it to complicated and lose sleep over it. A good set of headers with unrestrictive exhaust wins the low cost battle. Let the big budget teams do all the science.
Many overlook what happens when they use long tube headers and long tube intake runners they expect a large power increase and they get one but it could be very peaky. You may end up with high torque motor but in a narrow power band. I've read of a trend to unequal length header tubes to broaden the power band even though many will disagree I'm sure.
IMHO don't make it to complicated and lose sleep over it. A good set of headers with unrestrictive exhaust wins the low cost battle. Let the big budget teams do all the science.
01-24-2018, 10:57 PM
#54
Race Director
Member Since: Apr 2007
Location: South Western Ontario
Posts: 11,061
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One conclusion is that a pair of tri-Y headers no optimized for the engine but instead fit into the application don't reap any expected rewards. Just looking at the AFE headers, to me it appears the primary tubes to the first Y are too long. Possibly, that was the only area where the Y's would fit into the car. It's also possible that was the engineered location but they got it wrong.
Another conclusion you can make is that ARH actually knows a few things and did some engineering and is not simply throwing together a header with 4 long tube that fits into the car so they can make money.
Another conclusion you can make is that ARH actually knows a few things and did some engineering and is not simply throwing together a header with 4 long tube that fits into the car so they can make money.
01-25-2018, 01:11 AM
#55
Drifting
Adam,
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
01-25-2018, 03:48 PM
#56
Melting Slicks
Thread Starter
Adam,
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
Adam
01-25-2018, 03:49 PM
#57
Melting Slicks
Thread Starter
Adam,
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
I don't recall seeing what size headers you have but I am also running Profiler 195s with some mild porting and I couldn't use 1 5/8" headers and had to step up to 1 3/4".
Do a gasket match between the heads and the headers to confirm-
I found out in the 11th hour that my 1 5/8" headers would restrict the exhaust ports right at the head.
Elm
Adam
01-25-2018, 04:23 PM
#58
Melting Slicks
Thread Starter
If I wanted to make my own custom headers (I never will; I suck at welding) or pay for someone to fab them up, I'd definitely take advantage of the Burns Stainless X-Design service. (Burns is the guy who co-created the merge collector with Calvin Elston.) -If you buy your merge collectors from Burns, you fill out the Engine Spec form (you'll need a HUGE list of intricate details including exhaust port height and area) and your goals and they'll give you a complete end-to-end design of the exhaust that's ideal for your goals / engine. -Then take it to a header fabricator and have them weld it up. (I'd love to give my Vette a custom set of headers for it's 40th birthday next year, but it's probably getting a paint job instead...)
This way you're just paying for a set of merge collectors and you get a professionally engineered exhaust system that you could have someone local/cheaper fab up.
http://www.burnsstainless.com/x-design.aspx
Last edited by NewbVetteGuy; 01-25-2018 at 04:24 PM.
01-25-2018, 04:59 PM
#59
Drifting
I've heard loads of fitament issues with the raised Profiler exhaust ports. Was the restriction just at the top of the exhaust ports because of the raised exhaust ports in the heads? -If so, would elongating the bolt holes so the exhaust ports can be centered on the heads' exhaust ports work, you think?
Give it a close look to make sure you aren't creating a restriction.
Elm
01-25-2018, 05:14 PM
#60
Drifting
Sorry if it has been covered as I only scanned through the thread but...
What's your plan for a hood? That thing has got some height too it. Almost looks the same as my mini blower.
What's your plan for a hood? That thing has got some height too it. Almost looks the same as my mini blower.