welp, my rear has about had it so its time to beef it up a tad.I will be buying all the parts and having a drivetrain shop set the rear.
i want to stick with the 10 bolt for now and have a few questions. What all do i need? i want driveablity and able to hold up at the track with some et streets. I was thinking about the eaton posi http://store.summitracing.com/partde...=ETN-19557-010
(is this even the right one??)

moser axles
http://store.summitracing.com/partde...rt=MSR-A102804

and the hardest part the gears. I have no clue what i should get. I want at least 3.73's for the engine i have, but running a 700r4 could i go 4.10 and not be kicking myself all the time car has to drive 23 miles a day and 35 miles to the track. It has a 2500 stall if that matters at all.
so what am i looking for in gears?? all i know for sure is it has to be 10 bolt. i dont kow what pinion spline i need or tooth count

last part. I want to be able to say here are all the parts. What extras will i need?

any help is greatly apreciated THANKS!!

1988 Firebird
350, 700r4

 

No no no! That posi is for a GM 8.5" 10 bolt, ie a 1976 Camaro for example.

You want something like this
http://store.summitracing.com/partde...5&autoview=sku

Those axles look good. Look seriously at Superior axles. They are heat treated after machining for more strength.

3.73's is as high as you want to go. The 700R4 has a very low first gear. with steep rear gears you get.... Well, you remember learning to drive on Grandpa's old truck? Yea, you remember the "creeper" gear, first gear? And how you skipped it? yea, like that....

Your engine, cam and stall scream 3.73 gears.

You will also want a "girdle". Summit house brand one is $230 or so. Look at Ratech's 4111 part. The solid pinion spacer. Other then that, I think you're set.

 

For a differential carrier, you might consider a Detroit Truetrac, a gear-type limited slip, I have heard good things about them.

Summit Parts Link

I would suggest 3.42 or 3.73, like Sonix said, the 700R4 has a steep first gear (3.06 as I recall). 4.10 would be a lot of gear.

You might read this too:

ThirdGen technical article

For what it's worth, I was in the same spot as you and decided to save my money for a Strange or Moser 12-bolt. I couldn't justify spending a lot of coin on a weak rear end, when for a bit more, I could have something virtually bulletproof.

 

Thanks for the replys guys. If cost of parts and labor are close to a 12 bolt i will baby the car till i have enough for the 12 bolt. I would prefer to get a moser 12, but my car is a cash car. Yeah grandpas old farm truck sucked!! I think im letting that lil bit of cash burn a hole in my pocket. Thanks again for the info. Another question though. Is setting up a rear really that hard? i mean i built my engine and people said that is a pain but i liked it.

 

sonix. i see in your mod list you run the tru trac, how do you like it. it is quite a bit cheaper that the eaton posi unit.