85F-body

i am thinking about getting a whole new drive train and getting a 410 posi in it and i know that the 410 gives fast acceleration but will i be able to take it on the highway and does positraction help performance wise?

Nitro Don

If you have an auto,I wouldnt get the 4.10's
Your RPMs will be REALLY HIGH.Take it from me,I ran 4.10's in a 700R4 for one year before I went to a 3.73,which is a much better gear for a street drivin 700R4 car.
Nitro Don

spud

I have 4.11's and a th350 so my final drive ratio is 4.11, with a TH700 the final drive ratio would be 2.59. Or about 2200-2400 rpms at 65mph. They shouldn't hurt your gas mileage to much, but it will dip slightly. I'd recommend it especially if you race it often, Just by changing gears I cut one half of a second of my 1/8 mile time, in which translates in to three-quarters in the 1/4. It was worth it to me.
John

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82 Firebird,355,Cam 224/234, .466/.488,TH350 Tranny,650 HolleyDP,Hooker Headers(I.E. POS) Manual steering
Best 8th et 8.62@80mph.
NEW for 01
A 408,dart iron eagle heads,street dominator intake, 750 SD,cam 229/239, .497/.520, Also a big hole in the hood.
Shooting for 12's.

85F-body

if i get a 410 should i have to recalibrate

Killer-Z

I read once that 3.42 and 3.73 are the best gears for tpi with 3.42 being the more desireable.

The ODB

my own testing has shown that 3.23 gears work best with TPI. The 3.42 ratio is really close to this.
The 3.73 was actually equal in performance to the 2.73 ratio when used with the TPI.
just FYI

410GEARRATIO

I have 4:10;s and it is the best thing for my car considering i have the 170bhp 305tbi and 700r4 auto, gas has not really changed and I
love the fact that i can keep up or beat most of cars that would stomp on me...
jon
mods: 14x3 open element air filter,
underdrive pulleys, hypertech stage 2 chip,
160 thermo, 160 fan switch,gutted cat and of course the 410 gears.

import'sdread

I've had good luck with my 3.73's. At least on the street. When I don't spin the tires, I get huge leads on cars that are much more powerful than mine. On the street, that's all that matters to me. The gears seem to make my car appear more powerful than it really is. I'm running the stock TPI, and I've beaten cars rated at 300HP on the street! This racing is pretty much light to light, but I think you can see my point.

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1989 Trans Am, 305 TPI 5-speed, T-Tops(love 'em),4-wheel disc, 3.73 posi