JT76

My car used to run 13.6's at 101 or so, now its 13.9's from anywhere between 95 and 99 mph.....I had the car re tuned after the LT headers but something isnt right obviously.....i have been waiting to make another appointment at the Dyno shop but the guy just had a kid and who knows how long he will be out....this weekend is the "Khumo street wars" aka rice fest and i want to go lay down some hurt on the 16 and 17 second ricers....is there any way i can fix this or what? Im taking it to the dyno as soon as i can but anyone know a "patch".....watch the vid and see what i mean, several ppl have told me the car is "pulling timing"...car is an auto

http://www.youtube.com/watch?v=ngu3Pn-g-zc

falls on its face after the shift to 3rd

again, in car, you can see the tach at the left hand side
http://www.youtube.com/watch?v=06EfveS296M

adam_ferguson

sounds like a ECU problem. when they tuned it did they tune your AFR? that would cause it if they did it wrong.

LetThePoniesRunFree

Do you have comparative time slips from pre/post LT's?

The reason I ask is that some times with a n/a motor you will actually loose torque with headers in the lower rpm band depending on the diameter of the tubes.

Nothing replaces the screw driver of the muscle car days like a lap top computerand data logging.

2000GT4.6

youtube FTL man, streetfire FTW! I can't see the vid at work but...

So far as pulling timing, why would it do so only in 3rd gear? The only reason I can see they would pull timing is if the IAT reading increases... but thats usually only a concern on FI cars.

What is making you think the car is "falling on its face" in 3rd? Have any of your times before 3rd gear changed at all? Launch?

What was your a/f ratio on the dyno? What kind of timing setup did they put in? Did you tune with a handheld or a chip? If its a handheld, try dialing in another degree of timing and see if your runs change (so long as you get no ping).

JT76

currently my timing is maxed out as far as the predator is concerned....my launch times are consistant and my times in general are pretty consistant up to the 330 foot mark, its downhill from there.....as soon as it hits 3rd gear the car just falls flat, the rpm's "stick" you might say for like 1/2 a second it seems

ackuric

your problem is third is a 1.00 gear ratio and it doesnt really kick in until 100+ mph, from 85-95 its a turd gear, so, dont ever expect it to put you back in your seat w/o f/i or a major build. you're better off getting some cam/head work and revving up a few more hundred rpms to help the powerband in third when you hit it at wot.

the lt/s and midpipe wont do you any good w/o f/i.

i bet if you posted the specifics on your 1/4 mile times from pre-lt to post-lt we would be able to tell if you are losing the power at launch/low end, or on the stretch/top end

JT76

well if this is the case....these cars are now officially garbage....probably the only car i have ever herd of where adding mods slows you down....unbelieveable

Pest007

You just have to add the right mods to get what you want out of it......not garbage

JT76

how the hell would adding long tube headers make me go from a 13.68@101 to 13.9 @ anywhere from 95-99...makes no sense at all...apparentlyi picked up rwhp (17 to be exact and a similar tq)....i still gotta believe its in the tune

2000GT4.6

How can you possibly say that? LTs and the midpipe are the two single biggest gains to be had on a bolton only car, nothing else bolton wise compares.

LTs and a midpipe will take a stock 225 WHP car and make 245+ WHP easily. Typical gains are 10-15 for the LTs and 8-10 for a good midpipe.

Something isn't right, it should not be pausing when it goes into 3rd gear, regardless of ratio. None of the other auto cars are having this problem. I would take the car back to the tuner and explain the problem.

One last thing, how were the track temps? I know temp hurts me a TON, and so does humidity.