coptzer

iTrader: (2)

So I'm close to getting this done, and I'm ordering an S60 with Truetrac this week. I've got a H/C/I LS1/T56, nothing too crazy, 230/238 cam / 243 heads / LS6 intake. I will be using stock IROC wheels and tire size for now, and I'm trying to decide which gear to use. This is mostly going to be a street car with minimal track time and I am leaning towards 4.10's. I have heard that with 4.10's it is fun as hell to drive, but am hearing mixed opinions between 3.73's and 4.10's and I only want to do gears once!

A lot of it is personal preference, but I'm trying to get some input from people who have their butt in the seat of a similar setup. Of the 2 choices, what are you running and are you happy with your choice?

86White_T/A305

Im debating what gears to use also..but im still stock rear which is not very strong if I take it to the track more often.Im leaning towards 3.73.Would like to see what others recommend

Jaysz28

iTrader: (30)

match the gears to the cam and then you won't be wrong

I am personally running 3.73's in my setup and I like it for around town driving. I don't go to the track enough to warrant 4.10's

QwkTrip

iTrader: (22)

A lot of people are worried 4.10 gears are too aggressive. That's old school thinking before double overdrive transmissions and engines that scream to nearly 7000 RPM. If I put you in a LS powered car with 4.10 gears, I bet you would not even know unless I told you. It just feels right with a T56 and will help a cammed LS1 get into power band where it needs to be to perform.

Similar concept with modern auto transmissions. You can run with much higher stall speed than in the past and it will drive fine.

STREETDEMON

4.10s in my 8.8 hybrid and it works great. mine is not a dedicated track car and i was worried when i first put it together, but they have been pretty awesome.

at 80mph i'm still around 2k rpm in 6th gear. with my 230/232 cam it was very sluggish with the 3.23s, the 4.10s made a great difference. i would like to try 3.90s, but definitely would not go to a 3.73.

coptzer

iTrader: (2)

Completely agree! I guess I just needed some enlightening from someone with experience...haha! I went ahead and ordered it with the 4.10's last night. "Go Big or Go Home" right... Even though I was leaning 4.10's, the guy I ordered it from completely convinced me once and for all. I can't wait! Gonna be fun!

Thanks for the input.

25th327RS

iTrader: (2)

I am running a 232-234 cam with ls6 heads and intake on a 6.0.

I have 3.90s in a 10bolt rear. Had 4.10s at one point, and may go back to them with my 8.8 hybrid swap that is currently in the works.

Either way, I love both the 3.90 and 4.10 for a t56 car.

coptzer

iTrader: (2)

Thanks for the input guys. I know I will love them. I have a brand new set of 3.73's and was originally going to use them on my 10 bolt for the short term. But they will not work in my rear. My car was supposed to have 3.23 from the factory. Window sticker says 3.23, build sheet says 3.23, but when I removed the rear it has 2.73. So the gears must have been changed by the original owner at some point and now the 3.73's I have are the wrong series. So I just decided to suck it up and go with the new rear now and sell the 3.73.

I was going to build an 8.8 but could not find a decent one around here with a good gear ratio and posi.

86White_T/A305

I got a 9 bolt so all i can try is a 3.70 gear iirc

QwkTrip

iTrader: (22)

3.90 gears is the practical limit to what you can do with a 10 bolt because 4.10 pinion will snap like a pretzel. Also, experience among my circle of friends is that GM gears have the highest quality and best metal of any gear on the market for a 10 bolt.

tvc 15

I have 4:10s in mine and first gear is pretty much useless. If I had it to do over I would go 3:73s.

STREETDEMON

time for you to invest in some sticky tires.....

coptzer

iTrader: (2)

Hey STREETDEMON, how do you like the 4.10's? Just curious. I can't wait to try mine out. I'm going from one extreme to the other. I found out my old rear had measly 2.73's... blah!

1991sleeper

iTrader: (-3)

Also remember our gear ratio is based on s 26" tall tire ... bump that up to 28-28.5 and u have 3.73's

91' bird 305 TBI T-5, trick flow heads, 4.10 gears, full UMI setup, track times coming soon!

1991sleeper

iTrader: (-3)

91' bird 305 TBI T-5, trick flow heads, 4.10 gears, full UMI setup, track times coming soon!

STREETDEMON

They are way better than the 3.23s. The factory gears made my cammed 6.0l sluggish off idle. Now it just rips to 7k rpm. Definitely invest in a set of sticky tires if you want to dig in 1st gear. I have read that the 4.10s aren't dyno friendly and that showed during my session. Track times will prove the real numbers. I'm happy I went this deep for sure.