First off, here's the facts: 99 Z28, A4, 2.73 gear with 96,000 on the clock and 100% bone stock on 16" street tires. Weather was pretty good, low 70's and low humidity, kinda windy though. Only made 2 passes, with about a 20min break between runs. They looked like this:

First run:
Reaction: +.269
60 ft: 2.071
330ft: 5.813
1/8 ET 8.872
1/8 MPH 81.20

Second run:
Reaction: +.146
60 ft: 2.051
330ft 5.791
1/8 ET 8.844
1/8 MPH 81.23


I was really hoping the car could pull 82mph, as you can see it didnt happen. Should I be disappointed or is the car on par for the mileage/tranny/gearing? Any feedback is greatly appreciated. Thanks.

Joe.

 

Sounds about like mine.

99Z Auto

Reaction - +.232
60 ft. - 2.099
330ft. - 5.733
1/8 ET - 8.712
MPH - 83.30

Only thing I know that's done to mine is an SLP lid. First time ever racing too. Best reaction of the night was a +.014.

 

That's closer to the MPH I was hoping for, but I guess I shouldnt complain too much for the mileage. How many miles do you have on your car? Those are nice times by the way. I take it you never ran the car without the lid, huh? I guess that's my next plan is to go with a lid/exhaust and see how much that helps out.

Joe.

 

60's look alright, to sure what that calculates to 1/4...never ran a 1/8 track here

 

No I never went without the lid. I just got it not too long ago and it has 37,000 miles on it. I had to upgrade from my 94 3.4L.... it's a little bit of a difference.

I know this is a dumb question, but where do you look to find out what gears you have? I looked on the rear end and don't see anything. The owners manual wasn't included either. It has 1, 2, D, OD... A post I searched earlier stated that meant it was a series 3 carrier, but then another post said that GU was the code for the gears and on my door it says GU2. Any clue????

 

GU2=2.73 gears, or you can more or less tell from the rpm's at 80mph, it should be turning ~2000rpm with 2.73's.

I guess almost 3 times your mileage and I've only lost a couple mph, so I shouldnt complain too much, huh? Dang, I can feel my wallet getting lighter already from just thinking about the modding, lol.

 

13.7's@102 is about what you would have ran in the quarter. A little on the slow side, but nothing wrong it.

 

Uhhh....no.

I think you mean 9.0. My car did 8.4 in 1/8th and ran 13.31. Then before the converter it ran 8.8 and did a 13.5. 8.0 in the 1/8th would be well into the 12s.

 

2000rpms at 70mph.

If you have the 1st gear selector, you have 3.23s. If you don't have the 1st gear selector then you have 2.73s.

 

I'm not sure if that only applied to LT1 cars or not because I also have the selectable 1st gear but with the code of GU2, which is definately a 2.73 gear. And it does turn ~2000rpm @ "80"mph, not 70. 3.23's may run 2000rpm at 70mph, but I was referring to 2.73's. Can someone back me up on this?

Joe.

 

My 2.73 car runs 70 at 2000 rpms. And I really doubt the LS1 A4 cars got different gear ratios.

 

Would have been a 13.6-13.7 @ 102-103 in the 1/4.

 

98 mph. 1st gear ends at 52. I am so happy that I got rid of those.