What is a good gear Ratio for me?

[LT1MAN]

Ive been looking around for more modifications for my lt1 and a rear end gear set seems to be a pretty good option. i was just wondering if yall could tell me what some of the different ratios did, for instance more off the line or top speed. basically i want to get more grunt off the line and still at least be able to go 150. i also heard these gears kill your gas milage, and you have to reprogram your computer for your speedo etc.

preciate the input fellaz.

[FormulaLT1]

I'm very happy with my 3.73's but if you have a 6 speed you can go upto a 4.10's without a top end problem because of the extra overdrive ratios. Also I didn't notice that big of MPG difference with my new gears but off the line is amazing.

[lckycharm713]

3.73 are good. but i dont think you will get to 150. i dont think you'll get that at all. no matter what gear you have. the bigger the gears (4.10) more off the line. smaller the number, (3.73, 3.55) more high speed. i read that ppl that put 3.55 in there cars (not sure it was the mustang or camaro) didnt get much of a difference. im not sure about this, but if you put 4.10, you have to get a posi rear? i dont know if you have that or not.

[FormulaLT1]

LT1's can easily break the 150 MPH barrier, Infact L98 Camaro's with 60 Less horsepower can hit the 150 MPH Mark, Also all LT1's came with Posi (or actually Limited slip). but with 3.73's top end will be somewhere in the 140 -150 MPH mark in Overdrive not that , that should matter because street racing that fast is dumb as hell

[LT1 Kayker]

does an 89 Z28 have posi? I think it does but just wanna make sure, and Im getting one with an LT1 swap in it, and i want to put in a T56 after it gets shipped. (already baught it) would 4.10's be good for that? Its in the Sig.

[FormulaLT1]

Yes 89 came with a 7.5 Auburn style Posi unit same one used in s10 trucks and yes a 6 speed would work great with some 4.10's

[LT1 Kayker]

Ok cool thanks.

[lckycharm713]

i dont think 89 had posi, both my 85 z28 did not have it. they have a Limited slip. my cousins friend has a worked 3rd gen. camaro and he burnt up rears like crazy i was told. i heard the guy knew his stuff, but i never seen what he did. im not saying your wrong FormulaLT1 , just make sure.

[FormulaLT1]

Limited slip and Posi are basically the same thing

[LT1 Kayker]

Basically both tires will spin in a burnout, and power is put to both back wheels....? Right?

[FormulaLT1]

Well there are 3 type's of Posi units
1. Locker- which supply's 100 % of equal power to both wheels at same time unless your turn which will cause the outside wheel to continue turning while the inside wheel will be unlocked.
2. Limited slip- Sense's slipping and uses bearing to allow other wheels to take on more power. These units usually supply more power to one wheel than the other. Thats why they fishtail on wot take off's.

3. Traditional Posi . Provide 50/50 split of power between both wheels and usually will produce equal length and darkness strip upon burning out

[lckycharm713]

when i did a burn out, it was ONE tire. "one wheel peel" both would spin in the dirt. you dont want this. less tires spinning = less traction. both tires more grip.

[twdz28]

3:73, Did 155+ in a 6spd car... Love the gears for take off...

[89IROC&RS]

My 89 IROC has posi, although its not auburn style, its a borg warner rear end, auburn was fourth gen camaros, and then torsen followed that. the posi for third gens is the 9 bolt rear end with the borg warner option.

[FormulaLT1]

I'm sorry to disagree 89 but a Auburn style 10 Bolt was used on production cars in 89 there may have been a 9 bolt used too but the 10 bolt from 88 1/2 -02 are interchangable 10 bolts. Just check this salvage yard site www.car-parts.com and do a search for your rear