So I did a bit of searching and found out that my 4-speed automatic is geared for 2.73 (according to the GU2 code in the glove box).

I'm not sure if I want to start messing with it yet by going with 3.23 gears (I read up some old threads about it).

Anyway, probably a dumb question but it's unclear to me; do I have a 4L60 transmission or the 4L60E?

Also, would a transgo shift-kit be any good or should I leave it as is? Do the benefits outweigh the cons? What are the cons if any? Car is a daily driver and I don't take it to the track and won't for another 2 years or so.

The car is completely stock so I'm thinking when extra funds become available I'll look into upgrading the exhaust system as well as the intake so I won't be doing anything to the transmission for awhile.

Thanks for any advice! Loving the Z28 that's for sure, especially after getting rid of my turbo'd front-wheel drive.

Guess what I was looking at was the B&M Shift Improvement kit.

Should I mess with this at all?

Or should I look into;

Transgo HD-2 kit or the E-3 kit?

I saw that the E-3 and HD-2 are the same, however the E-3 basically converts your transmission into manual (full manual valve body conversion kit). If that's the case, guess I'll look into getting the HD-2.

So Transgo HD-2 or B&M Shift Improvement kit?

It's the 4l60E. As for the gears I would go with 3.73s.

I haven't really read up on the shift kits so I can't really offer you any good advice on them.

The TransGo HD2 kit is a very nice shift kit. The B&M is generally considered lacking in many areas.
Your 4L60e is not geared to any particular rear end ratio. From the factory they came with a 2:73 rear unless you got the performance package, which came with a 3:23 from the factory. The most widely accepted upgrade for a normally aspirated automatic is the 3:73 ratio.
Only the 93 came with the 4L60. The "e" stands for electronic control, which came out in 94.

Thanks guys.

I've read about 1-2 different posts on older threads stating that 3.23 gears eat up a bit more gas when they're upgraded from 2.73 gears? Not sure how true that statement is.

Also, there's a type of whine made when doing this change? I think that's the whine I'm hearing now coming from the rear?

As for shiftkits, I'll go with the HD-2 kit then when funds become available. Wonder how much a kit would cost to upgrade to 3.73/3.23 gears. As for a reputable shop, I know of a father-son shop that's done work for me on my other cars when I didn't have the tools for it.

I believe that with the 3.23 gears, it will hurt your fuel mileage compared to the 2.73's, the lower gear you have the lower your mpg is. In this case lower is higher (I think). Meaning a 4.10 gear ratio is low and a 2.73 is high.

Not to throw a wrench in here but at one point I had an '87 Camaro with stock 2.73 gears and switched them out for 3.42s. I actually ended up getting better gas mileage with the 3.42s than the 2.73s. I noticed that the trans did not "lug around" in high gear as much with the 3.42s. It seemed like it was more efficient and had noticeably more power, or at least the power band was more useable. It may depend on how much highway driving you do, or visa versa. The rpm difference at 60mph was about 1700/1800 for the 2.73s compared with ~2200 for the 3.42s. This was with a 700R4.

Just wanted to add a differing point of view.

Greg

Yenkohead, you are correct in that optimal fuel economy will be achieved when the vehicle is operating most efficiently. Slipping the torque converter by lugging the engine will decrease fuel economy. Clearly on the highway the 2.73s will deliver better fuel economy. Around town it depends on the type of driving. Obviously, when you put your foot in it the 3.42s will deliver more performance at the cost of decreased fuel economy.