Hey guys, haven't been on in a while. I'm in need of some help/advice. I need to know what rear gear would be optimum for me. Engine is a 327 that makes peak hp at 5500 and peak tq at 4800. Lunatic VooDoo 268 cam. The tranny is a WC-T5 from a '92 Z28. Would I be better off with 3.73, 3.90, 4.10 rear gear? I'm thinking the 4.10 will be too short. If it matters, the engine makes 360.7 hp and 361.3 tq.

 

well, gas is supposed to hit $5.oo a gallon this summer. id go with 3.73s. just one opinion.

 

ya, I heard about that 5 dollar a gallon price too. So much for a improving the economy. Its already 3.99 here for 87 octane and usually were cheaper than the national average

Id go with 373 or 342s. those 5 speeds have a low first like a 700r4 i think. Ive read on here some guys start out in 2nd because they went to a 373 with a manual trans cause 1st is to low.

Im thinking about 4.10 in my car but I'm thinking it might be to low. And i got a th350 trans in my car. 3.90 and lower is more for race only as far as my opinion goes.

 

Thanks for that, but this car is definitely not a daily driver. Our gas prices are $3.62 for 87. I hope that a 3.42 wouldn't be too high since this is a short stroke 327, but I am thinking that between a 3.42 and 3.73 is gonna be my best option.

Come on with some more feedback guys.

 

Ive had both a 3.42 and a 3.27. I wouldnt go more than a 3.42/3.45 honestly unless you really dont care about the engine screaming on the highway. With a 3.73 you will be running the motor at 2,900-3000 rpms at 75 or so. My buddy has 3.73s and a t5 in his car in back of a vortec high comp 355 and he likes it but he doesnt drive it on the highway all that often (or drive it often at all lol). 3.42s would be a nice balance between cruising and all out from a dead stop. The only reason i still have 3.27 gears is that my first gear in my tko is retarded deep (3.27 first :O). With a t5 you'll like the 3.42s.

Basically gearing is all about compromise in one form or another. Do you want to go really really fast from a dead stop up until redline or do you want to be able to cruise on the highway at a low rpm? With your peak power coming in at 5500 i dont see 3.73s being that much use to you. If you were making power up until say 6500 or 7000 then i would say go for it.

 

Hmm, I was wondering about this too. If I have a T56 in my car, do you think 3.42 / 3.45 or 3.73s would be better.

I have been looking at 3.73s because I was thinking the 6th gear in the T56 would make up for them when cruising on the highway?

 

With a 10-bolt I wouldnt suggest going past 3.73's. The pinion gear teeth start getting pretty thin when you go to 4.10s.

However, with a T56 streetability with 3.73's is a complete non issue. Im below 2k RPMs at 70mph. You can run 4.56's with a T56 and still be at less RPMs on the interstate than a 700r4. I think in general 4.10s are probably the best gear for T56s because they do have a relatively tall first gear, but I blow through first gear so fast with my 3.70's as it is that Im not sure 4.10's would make my car faster at all.

I think the rule of thumb is to pick either peak torque RPM or peak hp rpm... I forget, and target that to be your final RPM at the end of the track. So if you go to the track and you trap 100 mph. Get gears that put you at 100 mph in 4th gear. I dont think even in a T56, that the 5th and 6th gears can handle any kind of aggressive usage, although you'd have to have a pretty ridiculous gear to get to them.

 

Since this car won't really be on the highway I'm really leaning towards the 3.73's but something is telling me to go with 3.42's. I guess the 3.73's just sound better and will get me into my rpm band quicker, but at the same time, they will basically make my 1st gear useless. I forgot to mention that I'm still not sure what wheel size I'm going with, it's definitely 18's or 20's though. I know it won't be street slicks though, I DO want my tranny to last a lil while. LOL. What suggestions you guys have now since I forgot to mention my wheel size? Thanks again in advance.

 

No more opinions guys? I want to be very sure before I change my gears. I think the car has 3.23's in it now and with the stock 305, it pulls pretty good for what it is. I can get thru the gears pretty quick as well. Thanks in advance for any more help anyone can give.

 

Why do you say 3.73s will not be that much use to me. I know that the rpm band is a lower than you would think with the 327 but I also know this t5 won't hold up forever. The plan is to swap to a t56 after I destroy the t5,which hopefully isn't soon. Any insight to my wheel size with the combo. The car only has 15s on it right now but I will probably be going with a 20 in wheel combo since this isn't a racecar, just a fun street toy that maybe I can turn a few heads in the process.
http://www.tirerack.com/wheels/MiniW...d=true&sw=1280
This is what I'm thinkin I want with a satin black paint job. Wheels are staggered and will have 265/30 on the rear and 245/30 on the front.

 

If your already planning on doing the t56 and are sure your going to do it than go for the 3.73s. You wont be sorry then. If you were going to stick with the 5 speed though i would tell you to reconsider just because its a LOT of gear for something that is just going to be a fun cruiser. You will be up and out of your power band REALLY fast with 3.73s and a 5 speed. Yes it will get you into your power band quicker but also up and out of it, meaning sooner shifts which will actually slow u down a bit. Your highway cruising will be affected as well. As i said compromise. If you dont mind the higher rpms in every gear then go for it....especially if your going to throw a t56 in later. 3.73s with a t56 is about ideal. Hell i i know people with 4.11 gears and a t56 that can still cruise on the highway at 2500 rpms.