Can someone please explain what will give my C5 more low end torque????? And what mods are going to adversely effect it???? A schooling on the subject would be great...lol

Doesnt back pressure cause low end torque(and if this holds true why do some claim x pipes give you more low end torque if they make gases mix and flow smoother??) So flowing more air decreases low end but helps upper end?(adding perf exhausts, hf cats, etc)


Thanks Guys
(gotta learn somehow)

:conehead

 

ttt

 

A set of TTS Long Tube Headers with 1 5/8" diameter primary tubes will help out big time in the low end.. This is why I love these headers so much, they add torque down in the lower RPMs which you feel everytime you drive your car.. This is also why these headers were designed this way, so that their biggest gains arent found over 4000rpms.. Their very long primaries, as compared to some other popular LT Headers, also help greatly with low end grunt. These are also VERY well built headers with 1/2" flanges at the head, 3/8" collector flanges, jet hot coating inside and out..

Email me if you have any interest in a set!

 

I had the same request, I installed Long tube headers/X pipe and a 4:10 rear (I have an MN6) all I can say is WOW, it is totaly different car.
If you have a 6 speed, go with the 4:10's, if you have an auto go to a 3:42 and change the tq converter, you will feel it low/mid range.

 

I have a question for you, how do the 4:10's effect gas mileage, driveability, and top end power?

 

I do a lot of freeway driving, at 80MPH, I am reving at just over 2,100 RPM, my gas mileage has dropped maybe 1-2MPG, hard to tell, as I keep hitting the gas to feel the woosh. Top end, I really don't know, I have never taken the car over 140, and do not plan to, I drive only on the street, and found it much easier to drive away from a light/stop sign with these gears, also, fo some reason the GAGS is gone, I never hit it anymore. 6th gear is really useable now.
The car feels like it has more power, as it pulls harder, is this from the gears or headers or both, don't know. I made these changes about 5 weeks ago, if I knew how the car would feel, I would have made them months ago. The car really feels like it gained 30+foot pounds of TQ, it justy jumps off the line now.
Hope this helps

 

Back pressure does NOT cause low end torque, but backpressure can be used to cure a poorly designed/matched Cam/header combination.

Take the typical 1000cc sport bike motorcycle engine. These things have a valve in the exhaust that increases back pressure in the 4000 RPM bank. They need this because the headers are tuned for 8,000 RPM peak torque, and the cam is designed to allow the air pump to breatth at 12,000 RPMs. At 1/2 the peak torque RPM, instead of the header tune helping the exhaust flow by sending back a negative wave, it is sending back a positive wave, hurting torque. The exhaust valve damps the waves in the header, and cures the flat spot.

Back to automotive engines: A properly designed header for the LS1 should create a torque peak in the 4,000 RPM band, the flat spot at 2,000 RPM is so low on the rpm band, that not much wave action is taking place in the WELL TUNED header. So not much flat spot to overcome. The Cam in the LS1/6 has only moderate duration and overlap, so the engine is producing a good deal of TQ at the flat spor point (not true with sport bike engines) and the flat spot is not easily notices and not supported by the cam timing. Finally, the gearing of the automobile is designed to sprint through the flat spot quickly, so most of us never notice.

Therefore, Backpressure is not required well tuned automotive engines to avoid flat spots (n.e. create low end torque). And has in effect, been desinged out of typical high performance FACTORY engines used in typical high performance applications.

 

What gears did you get (brand)? whats involved cost wise and any computer recalib needed, etc?

Thanks for the help

Marc

 

yes;a rear gear ratio change will give a very noticeable SOTP improvement. You didn't say whether your Vette was 6 speed or Auto; but if its a 6 speed, there is absolutely no reprog or recalibration required. And in some circumstances, none is needed on the A4 either.

swapping rear carriers in a C5


[Modified by Mike Mercury, 4:18 PM 11/20/2002]

 

Got my gears from Andy, a forum vendor, as I have an MN6, needed no PCM programing. Cost for gears+ install was around $1700