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If I shift out of second at 5000 rpms on any road except a highway I'm getting points... If I do that for third I lose my licence. Actually if I do that at 4500 the same thing happens.
1st tops at 40
2nd 67ish
3rd at 94
And it takes about 13 seconds to be going that fast. Stock third gen or 84 vette. Limiting yourself to those rpms isn't saving you much.
That is exactly the mph range by the time I hit 5000 in first gear, I quick shift to second and floor it up to maybe 3000 before I have to let off in a 45 mph zone. Don't you see, I drive like I have a TPI car.
Last edited by Phoenix'97; Jan 1, 2018 at 09:51 PM.
Go read my previous post, why would you shift at 4500 RPM, it makes no sense. You would get no advantage doing that! Both engines have more then enough power to allow you to drive that car fine in the 2000 RPM to 2500 RPM range but when you decide to let loose then shift at 5500 plus with the LT1 while you must shift at 4500 with the L98 since it is way over its power band. As I listed before the power band of the LT1 allows you to shift later which allows more power/torque and acceleration in each gear then the L98 intake and possibly do. If you have some self imposed 4500 RPM limit then use the L98 intake but it will only slow your car down from stock while providing no performance gain.
The car has it's speed limiter set at around 6500 RPM. When I get into 6000 RPM, the car does not feel right, but that is probably the computer getting ready to kick in for the limiter. So this is what developed my shift point at 5000 RPM. I really have no need to shift later in the RPM band and the most my car is set for is 7000 RPM but I dare not put that kind of pressure and wear-and-tear on my daily driver! This is why the TPI intake is ideal for my driving style... I don't think I can make my case any more clear than this.
Originally Posted by bjankuski
Side note the 1991 L98 has 10.25 compression and the 1992 LT1 has 10.5 compression that is why I chose that graph to negate the compression difference. That .3 difference will only add up to a 1% difference in power so it is a non factor. The real difference is the L98 intake hurts mid and top RPM power with a small increase in low RPM power which is negated by the vast increase in mid and upper RPM power that the LT1 intake provides.
Well, this I did not know! You got me with this one. However, the lower torque number may be remedied with a B-body camshaft paired with the TPI intake on my motor, and with the compression increased to 12. Also I found these comments on the subject and I can't help but lean towards the TPI intake.
Originally Posted by MTVette
The L98 has lots more bottom end torque, and is generally quicker off the line. Its limited air intake slows it down at higher RPM. The LT1 doesn't give as powerful a launch, but has more top end power. Both can be modified to give much more power and torque.
Originally Posted by DarkHalo
Sure the LT1 has a few more ponies and at the top end 10+ mph more...I tend to drive a lot more stoplight to stoplight than at 150 mph though....Its a non-stop E-Ticket ride and Ill put my L98 ZF 6 speed w/ Dana 44 & 3.45 rear gears up against about anything on the road stoplight to stoplight....just my 2 cents.
Originally Posted by soundkillr
I prefer my 91. Drove both lt1 and l98 before I bought on and the l98 was more fun. I probably have a factory freak, but lt1's never gave me a problem in a race...
Last edited by Phoenix'97; Jan 1, 2018 at 10:08 PM.
That is exactly the mph range by the time I hit 5000 in first gear, I quick shift to second and floor it up to maybe 3000 before I have to let off in a 45 mph zone. Don't you see, I drive like I have a TPI car.
Uh... if you shift from first to second at 40 mph you're already at 3000 in second...
Uh... if you shift from first to second at 40 mph you're already at 3000 in second...
Yes? It's not much fun, is it? This is why I seek a torque increase on the low to mid-range using a very mild small camshaft set-up. The TPI intake is instrumental in this.
Well you have the LT1 intake, which is not set up for low end and midrange torque, its an intake that comes into its own in the midrange and on up. Its not the camshaft or the heads that will change that.
Best thing you could do to improve that low end and midrange feeling is to add 4.10 gears if its a manual, or 3.54(or 3.73) in an automatic with a higher stall TC. Then it will feel more like an L98 off the line because you're getting into that power band more quickly.
So then my focus would be on a midrange & up cam, more like the LE Custom or LT4 Hotcam. Have the heads redone and install either of those, and I think you'll be happy, AFTER you do the gears.
10% more rear gear is 10% more torque at the wheels. Relatively easy to do and will make everything else that much better down the road.
Yes? It's not much fun, is it? This is why I seek a torque increase on the low to mid-range using a very mild small camshaft set-up. The TPI intake is instrumental in this.
So you shift to second to go right to 4th... and you're already out of the so called sweet spot of the tpi as it peaks around 2800-3000 with torque... maybe 3200. I'd rather just be coming into the power band on that shift and have it stay vs in the middle of it then droping off but hey. I got a pos crossfire so what do I know.
The car has it's speed limiter set at around 6500 RPM. When I get into 6000 RPM, the car does not feel right, but that is probably the computer getting ready to kick in for the limiter. So this is what developed my shift point at 5000 RPM. I really have no need to shift later in the RPM band and the most my car is set for is 7000 RPM but I dare not put that kind of pressure and wear-and-tear on my daily driver! This is why the TPI intake is ideal for my driving style... I don't think I can make my case any more clear than this.
Do you think the factory would have put the stock rev limiter at 5700 RPM if then engine could not safely be run there?
Is your car stock or have a stock tune?
Well, this I did not know! You got me with this one. However, the lower torque number may be remedied with a B-body camshaft paired with the TPI intake on my motor, and with the compression increased to 12. Also I found these comments on the subject and I can't help but lean towards the TPI intake.
You cannot run 12 to one compression with a short duration cam, the cylinder pressure will get too high and cause detonation. That is why people raise the compression when they add larger cams, the increased static compression ratio makes up for the lower low rpm cylinder pressure. That is why I stated in my previous post to pick a cam with more lift, same overall duration but greater .050 duration to allow more air to enter the engine for more power and more low end power. You need to understand what each component on an engine does before you can decide how to modify it for more power/torque and power band. How does each item complement the other? I understand your goals of low end power but do not understand your lower then factory designed RPM limit because that goes against your other goal of faster 0 to 50 MPH times.
Go read my previous post, why would you shift at 4500 RPM, it makes no sense.
Because he's either a moron or a troll...or a moronic troll.
Originally Posted by Penix
Okay buddy, how does the TPI behave when you push it beyond 4500 RPM? No one wants to answer this one! Please, give me an idea about how the TPI effects the motor.
Asked and answered by many (including me) a number of times already. You're a troll. Can somebody please ban this jackass? Who here actually knows the moderators? I sent them all PMs a while ago asking them to ban this guy, but got no response. He has **** up this entire forum with this garbage, and somewhere there's a guy posing as an addle-brained F-body owner laughing his *** off at all the grief he's causing...probably over beers with friends.
Your comments are what foul up this forum, not people like me who have technical questions about motors and how certain modifications may work on those motors.
You've got it backwards....kind of like when you tried to tell me, that I was "full of it"...then you come back citing a broken car.
YOU foul up the forum. If you knew what was good for you, you'd listen to the experts...not argue with them.
Here, this is the last help I'm offering your :ing waste of forum space...
What's your custom intake & a cam swap going to cost you? It's going to cost you at LEAST $2k.
How about a solution for all of your criterial for 1/2 that? Spend a couple hundred for a stroker crank for your rebuild...there is your "low RPM TOWAK MONSTAH...then buy this(or some facsimile thereof) for winter....
Also I found these comments on the subject and I can't help but lean towards the TPI intake.
Originally Posted by MTVette
The L98 has lots more bottom end torque, and is generally quicker off the line.
What a slow learning, dunce. All of this^ was covered...THREADS ago, and many times. But ya still don't "get it"...do ya?
First, the very graph that bjankuski posted for you, very clearly shows that the LT1 actually makes more low end TQ. I bet that if you clench real hard, you can recall a similar but different graph that I posted (threads ago) that showed the exact same thing. The TPI doesn't make more low RPM tq; it make it's tq in the mid range; ~3200 RPM. That's not "low end" on a 5000 RPM limited motor.
The quote you're citing? The L98 is NOT "quicker off the line". You've been told this too, many times. Both cars 60' about the same; ~2.0x seconds and the LTq car is quicker in 0-60 tests...so how is a TPI car "quicker off the line"? It's not. So how is it going to give you that "real muscle car feel" that you wet-dream about? Best of luck with your overpriced, underperforming build plan.
Last edited by Tom400CFI; Jan 1, 2018 at 11:46 PM.
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Originally Posted by MatthewMiller
Because he's either a moron or a troll...or a moronic troll. Can somebody please ban this jackass? Who here actually knows the moderators? I sent them all PMs a while ago asking them to ban this guy, but got no response.
I saw when you did that and figured you wouldn't succeed. In general, the guy isn't being rude...so much as inanely stubborn. And, at times very slow. I don't know that there are rules against that.
I would submit it's just as much your continued "engagement" that perpetuates the thread(s), frustration, and feelings of regret. I've been through those stages -- when addressing the points early on. To a certain extent, I may understand the guy more than himself or others. But, he is like my last girlfriend and the president. He's too egotistical, stubborn, and short-sided to UNDERSTAND other points of view. In both their cases, I finally accepted they won't change because they are INCAPABLE. Same with this guy. That's why I gave up....even though there's more to say.
In some ways, the responders including you/I are being as much/more abusive than him. Again, he is incapable of understanding what mistakes, statements and aspects of his approach CAUSE that reaction. Just as my ex-girlfriend and our dunce president, the light is on -- but no one is really home.
Is that enough to be banned? I'll be surprised if it happens. Just like I'll be surprised if impeachment ever happens. Stupid talk, poor understanding...and even dumb links/pictures (tweets...LOL) isn't the smoking gun needed to pull the plug. Sometimes, the ONLY course of action is to avert your eyes and just look away.
I suggest everyone tries it.
Last edited by GREGGPENN; Jan 2, 2018 at 02:15 AM.
Reason: Added the last sentence
2020 Corvette of the Year Finalist (appearance mods)
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One more thing when talking about being banned. After seeing the graph below posted for about the 100th time BEYOND what it SHOULD be, it should be banned too. It's not representative of the differences in intakes/power.
The scale is so entirely skewed, that it makes the difference(s) LOOK much worse than they are. Stretch the graph sideways 2-3 times before you get a better comparison to a modern, more representative dyno graph.
I saw when you did that and figured you wouldn't succeed. In general, the guy isn't being rude...so much as inanely stubborn. And, at times very slow. I don't know that there are rules against that.
I bet you're right about the rules. However, I suggest at this point that he isn't stubborn, but is purposefully trolling this entire forum. This is a guy who claims to want to discuss engine theory in-depth for a special project, but every time you try to pin down a goal and make a facts-based case for a good way to accomplish it, he introduces some asinine new constraint or discovery, like: "My 02 sensor hasn't been working this whole time," or "But I refuse to shift my LT1 past 4500rpm even though my engine is set for 7000rpm." It's no longer credible that he is seriously trying to have a discussion.
But more important than his intentions are the effects on the usefulness of this forum. Thread-shitting like this ruins the search functions for those who actually want useful information. Basically, someone has to sift through so much garbage in any results of a search that the forum becomes useless. I'm used to another forum where stuff like this is never allowed, for that very reason. You also aren't allowed to start multiple threads about the same topic for that same reason, but that's something Penix has done here also. So it's really for the good of the forum that he should be banned, and this abortion of a thread should be locked.
You are 100% right about not engaging him, though.
One more thing when talking about being banned. After seeing the graph below posted for about the 100th time BEYOND what it SHOULD be, it should be banned too. It's not representative of the differences in intakes/power.
The scale is so entirely skewed, that it makes the difference(s) LOOK much worse than they are. Stretch the graph sideways 2-3 times before you get a better comparison to a modern, more representative dyno graph.
I'm going to have to disagree with that. Both the horizontal and vertical scales on this graph start at 0 and go beyond the top data, and they are perfectly linear. And both axes' scales are similar in size: i.e., the graph is almost square, so neither rpm nor torque/power are emphasized unduly. And of course both engine's data are plotted on the same scales. So it's the opposite of skewed. You can certainly stretch it out horizontally if you want to make it look similar to another graph, but that isn't going to change what it shows.
I bet you're right about the rules. However, I suggest at this point that he isn't stubborn, but is purposefully trolling this entire forum. This is a guy who claims to want to discuss engine theory in-depth for a special project, but every time you try to pin down a goal and make a facts-based case for a good way to accomplish it, he introduces some asinine new constraint or discovery, like: "My 02 sensor hasn't been working this whole time," or "But I refuse to shift my LT1 past 4500rpm even though my engine is set for 7000rpm." It's no longer credible that he is seriously trying to have a discussion.
This^.
Originally Posted by MatthewMiller
But more important than his intentions are the effects on the usefulness of this forum. Thread-shitting like this ruins the search functions for those who actually want useful information.
And this. The unwitting, coming here looking for GOOD information, may stumble upon this guys threads and become severely misled with horse manure.
I'm going to have to disagree with that. Both the horizontal and vertical scales on this graph start at 0 and go beyond the top data, and they are perfectly linear. And both axes' scales are similar in size: i.e., the graph is almost square, so neither rpm nor torque/power are emphasized unduly. And of course both engine's data are plotted on the same scales. So it's the opposite of skewed. You can certainly stretch it out horizontally if you want to make it look similar to another graph, but that isn't going to change what it shows.
If you want to get picky it is skewed if you are comparing HP and TQ and wondering why they do not cross at 5252 RPM. For it not to be skewed in relationship to each other the y axis which is the HP and TQ are not shown with same vertical numbers so the HP and TQ graph cross at 2500 instead of 5252. When I print dyno sheets for the customers at the shop I make sure I plot HP and TQ on the same vertical axis so it does not confuse people.
If you want to get picky it is skewed if you are comparing HP and TQ and wondering why they do not cross at 5252 RPM. For it not to be skewed in relationship to each other the y axis which is the HP and TQ are not shown with same vertical numbers so the HP and TQ graph cross at 2500 instead of 5252. When I print dyno sheets for the customers at the shop I make sure I plot HP and TQ on the same vertical axis so it does not confuse people.
Good point. It doesn't really skew the comparison, except that it makes the differences in torque look smaller than the differences in power. But it's a goofy and inaccurate graph in the sense that you pointed out.
Last edited by MatthewMiller; Jan 2, 2018 at 12:04 PM.
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.
:ing waste of forum space... 
Best of luck with your overpriced, underperforming build plan. 
It doesn't really skew the comparison, except that it makes the differences in torque look smaller than the differences in power. But it's a goofy and inaccurate graph in the sense that you pointed out.
