How can I find out what spline axles I have in the rear-end on my '92 RS?

 

I think they are 26 spline....yeah 26 spline, it's in all the literature....They are crap by the way....along with the hole rear end, but if you up-grade it it'll be alright

 

So, how can I change that into a posi?

Or would I be better off to go get an old IROC rear-end?

 

INFO: After mid-1989 All 3rd Gen cars were made with 28 spline axle shafts for both V-6 & V-8 models and all had 10-bolt rears after 1990. Also you will have a 2-series rear (2:73 gears) and that is another problem for you. Best solution would be to find a
1989 BW 9-bolt with a limited slip (aka posi) and the big rear disc brakes. Or with a stock LO3 RS, just live with it and only do one wheel burn outs with your power monster.

 

Your best bet is gonna be to find a 9-bolt rear. They came in the 85-89 IROCs and Trans Ams and can be easily identified by the 9 bolts that hold the diff cover on (as compared to 10 with the 10-bolt.) The only problem you'll run into is gearing. If you look you can find 3.27 or 3.45 gears, but most of the 9-bolts had the worthless 2.77 gearing. If you're REALLY lucky you might find a rear with a set of factory 3.70's....they're rare but they're out there.


You do have a 28-spline rear, and you could just get a $100 take-off posi from SLP and throw it in there, but you'll still have 2.73 gears and drum brakes. You can swap in a 9-bolt and have a better gearing and posi and disc brakes for about $250-300.

 

You know those LO3's are beasts when it comes to power! LOL. But seriously, I went to the local strip this weekend and did my burnout and actually got both tires to light up so....it looked as if i had a posi to everybody else. This was my first time at a strip EVER. I ran a 10.88 @ 64mph. this was on a 1/8 mile track. My reaction time was a .267 and 60' time was 2.416. Not too bad for the first time out in a pretty much stock 305.

 

wouldnt a .2XX be a red light??

 

No, not since they change from .500 being the best to .000 being the best reaction time.