I have a stock firebird with a 305 tbi and its a one legger what gears do i have in it right now? and if i put in a 3.42 posi rear what kind of difference, would it be noticeable?
thanks

 

Stock was a 2:73 10-bolt. So do some reasearch for replacement parts.
A 3:42 is 3-series ratio and you will need the same Limited slip carrier.
Your biggest concern would be the spline count on your axle shafts,they could be 26 or 28. 89 was the changeover to the 28 splines. Not a simple job changing gears, its up to you to decide if its worth it.

 

no im not replacing the gears im looking into buying a whole rear end with the 3.42 gears already installed. Whats the difference between the 26 and 18 spline? and would i feel a difference?how much?
thanks again

 

You won't have to worry about axle splines if you are replacing the whole rear end, b/c they will already be the right ones. If you are going from a 2.73 to a 3.42 you will feel a big difference in acceleration, especially with a posi. It's probably one of the most noticable mods you can do.

 

how in the hell would anyone know what you have in it now if you don't? why don't you get under the car and look.

 

how about theres no reason to be an a$$hole and i have been under my car sorry i dont check whick rear i have. Thanx for the responses other than the last one and is it a huge difference in acceleration? cause i just got a ticket and cant afford to get another

 

how about there's no reason to be lazy or stupid but it didn't stop you did it

 

as far as stock. it may not be the one mentioned. it depends on what options there were for it.. I now my berlinetta can with the 3.08 rear stock.. but it also had options for the lower (numerically) ones as well

 

thankyou angelis and for all the rest of you i dont have time to do it sorry. With all the school and work i hardly have time until winter. I havent even had the car a year now

 

you could have 2.72, 3.08, 3.23, or 3.42 gears, best way to check is punch in the rpo codes to find out which you have... (without having to tear open the rear)