Well 101.99 to be exact, I mean I'm not saying that for 100% sure, as its hard to tell exactly when you are crossing the 1/4 while looking at the tach, but it felt like it was. Maybe it was shifting exactly on the 1/4 mark, or a few feet before, I mean close. Is the stock shift point controlled by MPH like that? I thought it would just shift at the programmed WOT RPM and not be controlled by MPH? if not, you can hold it for at least a few MPH before the rev limiter correct? Maybe it has to do with wheel/tire setup since we're getting down to just a few MPH variance?

End point is that, 3.42s are trash for cars with similar mods as me, your better off with 2.73s in an auto. Only options should be 2.73 or 3.73, don't waste your time with anything in between. IMO of course.

 

Two things:
-Did you get your speedo recalibrated when the gears changed?
-Did you get your shift points reprogrammed when the gears were changed?

These are two different things that if omitted would definatly affect your 1/4 mile performance. Generally you should have seen the same or better times with a steeper gear and the proper tuning.

Oh and yes, the computer shifts based on SPEED not by RPM when WOT.

 

Yea, adressed thoose earlier in this thread. I did not know that about the shift point being based off speed however, so I would assume that I was technically in third then @ 102 trap, so I would be dead wrong in my assumption, just felt like I was crossing the mark while still in 2nd, damn camaros, just to fast!!! But still, seems that the 3.42s did hurt me overall though in the 1/4.

 

I would think there would be an improvement as well. IMO, how can you justify the loss it ET when the runs were made over a year apart? I mean, what was the corrected ETs for weather? And as I always thought, the trap speed is not the speed you cross the 1/4 or 1/8 mark, it is an average speed of the last xx feet at the track. Someone correct me here as its been a while, but if I remember right thats why all of those Gtechs posted higher mphs.

 

When I had my old hotcam/heads setup I ran consistent 13.50s at 106 with my 2.73s. With swaping to a 3.42 My first run was a 12.9 at 109. I opened the cutout and ran a 12.7 at 110. Best run ever with 3.42s was 12.56 at 111.8. My 60s dropped by 3ths.

It was a great mod. My mileage only dropped by a mpg or two.

 

No, No, I totally understand what your saying, I personally rag on people 24/7 that run at 50k mi, add a cat-back and go back at 100k and see a .2 decrease are all pissed, I'm like LOL 50k mi of abuse, god only knows what SES codes are up, weather, tires, etc...its all variables. I mean hell, the LT1 is so finiky and temp. related, I can turn my car off, and turn it on and gain 10hp, stupid computers =( But in my case, I made NUMEROUS performance modifications, that should have more than made up for the extra miles/time lapsed, everything in my sig except the K&N FIPK was done after the gear swap, then new times....and also the runs were similar dates and weather, just a year or so apart, similar tire wear, everything....I know for a fact that if you take a car with similar mods as mine, and swap from 2.73s---->3.42s you will see a decrease in ET, shoebox said it perfect, its just a matter of the wrong parts combination on my car, continued below......


My point exactly, your car is making way more HP than mine, therefore you are taking advantage of the 3.42s.....just like shoebox said in the earlier thread.....makes perfect sense. With low HP like my car, I can't rev the 3.42s out in 3rd before the 1/4 mark, also we cant really compare anyway as your not even running a 4l60e, I can't say for the gearing on 1-2-3, is it similar, whats the numbers?

Oh well though, I'm really wanting to do the T56 conversion, so the 3.42s should be ok for that for awhile.....getting tired of the autos, m6 is so much more fun, you guys think I'd see a pretty decent time decrease with just the t56 swap seeing the 3.42s situation, obviously driver dependent, but all things constant most people see a decent increase eh? from a 120k mi auto lol?

 

with a 6 speed it would be hugely driver dependent. i drive my car to the tune of a 13.4 whereas a friend of mine can easily cut a 13.1 without even getting used to it. It is really hard to digest the whole gearing slowing you down thing. i know for a fact that a 3.73 makes an auto car run a quarter faster. maybe 3.42's are just a weak spot for your car

 

Thats a very good point. A good example would be my old 92 Vette. With an LT4 Hotcam, ported heads, intake and exhaust with the stock 2.59s, the car trapped a best of 108 MPH. Now, with the addition of just 3.73s, with a slightly WORSE DA, the car trapped 114.1. My point is with significant mods, the gears will REALLY wake the car up versus just swapping the gears on a car with just boltons.

 

exactly... 2.73s on a minor bolton car are optimal... just my 2 cents.. 2.73s can surprise you sometimes...

 

I agree with all three statements 100% - and recommend that anyone swapping gears in an a4 car go with 3.73s minimum, don't be dumb like me and go with 3.42s to save a few bux at the pump

 

oh yeah...refer to sig...lol my car is almost a hustler no one expects the 2.73 gear car to run 12.2's...let alone a 1.5 60'

 

Nice.. Yea.. 2.73s are uhh sweet.. I like em... Imma keep em... With nitrous there good to.. Look at your car! Spraying outta the whole tho eh? with 2.73s im sure your rearend wasnt caring tho lol

 

ya, sprayin out of the hole, its only fun for hte first 1/8 mile, once it shifts to third, its pretty boring...

 

I have a 94 auto/3.73 gears and full bolt ons. I cross the line right at redline. See sig for my times. Only weight reduction is spare and I run an 1/8of a tank of gas. This is at ATCO raceway in NJ where it is only 40 feet above sea level/

I had an 88 350 Z28 w/2.77 gears. Like someone stated, great for highway and will pull more up top but for drag racing, go with 3.73 gears.

 

When I first got my 95z it had a factory 3.23 gear and I was running 14.10-14.20 @95-97mph with a k&n panel filter and airfoil. I had upgraded with flowmaster exauhst, no cat, Hughes shift kit, Hughes servos, Hughes 3000 stall, and a pcmforless tuning just for the converter. With that setup I was a running fastest time of 13.29@100mph 1.83 60ft crossing at 4800-4900. Now I have added a 3.73 gear and hold a new record of 13.27@101.5mph 1.80 60ft crossing at a tad under, if not, redline. I probally will be running 13.10s with a complete tuning but my car definatley could you use a cam.