New times...slower after 4:10s..why?
 

Okay last fall I ran a 14.2 with my 04 GT Automatic.

Well I have full exhaust,tune and 4:10s now.

the 14.2 was without Longtube headers and the 4:10s.

Well tonight i did 3 runs... these are with the 4:10s,LT's and new shift points

1st run... 14.49/93.26mph
2nd run... 14.50/93.24mph
3rd run... 14.84/93.07mph


I did feel in the 1st 2 runs that the car felt like it stopped accelerating when she hit 4th.


3rd run a spun so I know why that is slow.

But what gives? I thought I would have done much better

What were your 60 foot times?

By the looks of it, you either are driving poorly, or you are not making power. Your trap speed is really slow.

my 14.2 run before was...

r/t .5223
60ft 2.1479
330 ft 6.0358
1/8 e/t---9.21
1/8mph---78.41

ET 14.21
MPH 97.95





14.49 run tonight was...

r/t .5746
60ft--2.24
330 ft--6.11
1/8 e/t-- 9.31
1/8 mph-- 76.98
1/4 e/t--14.49
1/4 mph-- 93.26

Never let your car shift into 4th at wide open throttle:nono:
Turn off traction control and lock out overdrive to race.
As far as your times being slower there is only one way to compare trips to the track. You have to correct your times so you can compare. Atmospheric conditions, your 60' time all play into the equation. Good cold low humidity air will drop 2-3 tenth's off of your time. It's a pretty good chance that you had alot more tire spin with 4.10's than your stock gears. Bad sixty foot times equal slow et's. Gears will make you faster if you can hook. Also the tune on a automatic is a huge deal. If your car is short shifting due to the gear change you will be slower. Looking at your info I'd say you are shifting short, that trap speed is way low.

I had it shifting at redline from 1-2, i think 2-3 too. I never checked 2-3 or 3-4 cuz i was watchin the other car :bash:

O yeah i forgot... i was O/R last fall. I am catted now, dont know if that would affect much tho.

Cats cost you 10 hp. I know that when I started changing gears on mine the stock tune was poop. I had mine road tuned, we set the convertor lock up and shift points. To give you an idea of how much it can affect you my SCT chip has four positions. Position 0 is street tune car runs 13.60's pos. 2 & 3 are track tunes, car runs 12.80's - 13.20's depending on the 60'. It makes a world of difference.

Yeah, i need a new tune bad. I forgot about O/D too. I did have traction control off though. I just feel like **** having put new gears in her and getting this. I was hoping to break in the 13's

As to the 3-4 shift you don't want to go into overdrive for two reasons.
1. The tranny is not made to shift into 4th at w.o.t. it will brake in time.
2. It slows you down the gearing is way too high and you also drop your rpm's too low to make power hence the feeling of falling flat on your face. With your limited mod's you should be shifting at 5,600 - 5,800 rpm. Check and see how long it's taking to shift, mine would rev too high because it shifted too slowly. I put in a PA valve body and that went away. You can also do the J mod and that will clear up the slow shifting.

yea it felt like she died going into 4th. i need to find someone to do the jmod for me. i dont wanna drill a wrong hole of somthing. man i wish i had gotten a 5-spd :wallbash:

Not me. :devil2:

when dragging with an auto, O/D ON or OFF?

Looks like your car is having problems. You dropped 4mph and thats just like 40hp. I would make sure that your car is running right and yes the tune is the best way to go. I trapped 100mph last night with major traction issues in 1st gear. With your mods you should be able to run some 13s.

off, you do not go into 4th gear in an auto at wide open throttle at all.