Topic: Posi Differential help

[cerider43]

Hi I need help On my 1994 Mustang Gt. currently i have a stock differential and I want to switch it to a Posi as well as adding 420 gears. does anyone have advice how to do this step by step I really appreciate it

[ol dirty doug]

the gt should have a stock 8.8 posi unit in it from the factory. 4.10 gears is the way to go, i have not seen 4.20 gears and im sure they are 3 times more expensive due to the odd ratio.

[Soaring]

Yeah, I've never heard of 4:20 gears either. 

[cerider43]

it has the limited slip diff. and sorry about that i did meant 4.10 gears. so it's just the same as a posi unit?

[ol dirty doug]

ya if it slips just replace the springs and clutchs fairly easy if you are ok with tools

[Soaring]

Limited slip is Ford's way of saying posi traction.  Chevy uses the term posi tractiion.  If stuck in mud, one wheel will continue to pull even if the other one is stuck or off the ground. 

[cerider43]

thanks these advices really help. any more suggests you guys recommend. to actually get my horse power down to the wheels?

[Soaring]

What mods do you already have on it?

[cerider43]

bbk long tube headers with a x pipe, bbk intake forgot the suspension brand but it's lowered. i think that's about it. the previous owner took off the ac for lighter car? i have no idea why?

[Soaring]

Taking off the compressor for a street  car like you have won't make it faster for the street at WOT.  If you want AC, then get a Sanden compressor and have an AC mechanic install it. 

[cerider43]

yeah i thought so too, yeah im sure i'm going to do that the ac you need it sometimes.

[Jeff73Mach1]

simplest way to get your tires to hook up is to get sticky drag radials and run the pressure lower than you would for the street.

A pair of Mickey Thompson Drag radials will give you a much better launch for about 3-400 bucks or less if you can find some slightly used ones.

There are a ton of suspension mods you can do, but you have to have good tires if you really want to hook up

[cerider43]

thanks i will look into that and see what I can find