79 cutlass in need of posi looking for help and info

[cutlass79]

ok so im new to the gbf i have a 1979 cutlass that had stock the buick 3.8 v6 i swaped to a sbc 350 out of a 70 chevelle the motors all stock inside i put on a new 650cfm eb gbody headers 3''stright pipes into 3'' 40s flowmasters that dump infornt of the rearend set up sounds mean and its backed with a th400 love the set up for a daly driver but the stock 7.5 just aint gettin it i need a posi the car is my daly summer driver so im not looking to build a lot of power mit try to get more out of it in time but not till after i pull the motor in trans next winter for a full rebuild im just looking for the best posi set up for a 79 cutlass with out bumping a ton of money into it so whats a cheap set up to go with that i could find in a junkyard now i do still have my first car that is a 83 trans am that will be done up for the strip some day but its got the stock fbody posi in it any way i could ues that in any way? iv also heard good and bad things things bout the older s10 rearends just looking for a posi that i can do brakestands donuts and blow rice burners off the line daly driver to play with just looking for some info form a few guys thats been down the road im on with my gbody

 

[496kid]

i grab a posi unit from ether a g body with the g80 on the trunk,or i find a 4x4 s10 with a posi.f body's came with posi's also.

 

[pontiacgp]

it would help if you put down your location

 

[cutlass79]

is the s10 4x4 rear end any good as for a daly driver and i do have a fbody a 83 trans am and its got the stock posi in it how hard is the s10 rearend to put in or what can i do to the fbody posi rearend to put it in a gbody? im in rockford il about 80 miles east of chicago il

 

[jrm81bu]

Do you know what gear ratio the Cutlass and TA has? If they are both below 3.08 or higher than 3.23 numerically then the posi carrier is a direct swap. If not then you can use the carrier from the TA along with the TA's gears. The only thing that may be different is the pinion gear.

 

[cutlass79]

im not sure of the gearing on bouth cars but i can look it up and see if the posi carrier form my ta will fit will the cutlass stock axels work with it or would the spline count be dif..what would i have to do to find out what the gearing is off the rear end would it be on the outsdie at all or would i have to open it up to find out and if the pinion gear is dif what would i have to do to get it all to work togetter sorry i dont kno to much about rearends i can do anything with a motor and trans but never really needed or wanted to mess with a rear end but this car just NEEDS a posi in her

 

[DRIVEN]

They should both have 26 spline axles. I'm guessing the T/A has 3.23s. Tag inside console will give the axle code. Here's a list:
http://www.vibratesoftware.com/html_hel ... xles.htm#G
If you pull the cover the ratio will be stamped on the ring gear.

 

[jrm81bu]

Yes axles will be the same. And I messed up my last sentence. I meant to say the pinion bearing not gear, may be different. Just look up the inner pinion bearing for both applications and see if the part number is the same.

 

[cutlass79]

alright i was worndering cuz iv heard that the gbody spline is 26 count and the fbody is a 28 count spline but im not sure and what about welding the planitary gears to make it a posi i kno a guy that did it to his truck and its lasted years but just dont seem the best way to go about doin it

 

[DRIVEN]

My car was originally 2.29 open. I hit the U-Pull-It yard on half-off day. I pulled an Auburn (factory) limited slip from an '87 (I think?) Camaro that had 2.93 gears and 26 spline axles. Then I pulled the complete 3.42 gear set including the Gov-Loc limited slip from an '88 (i think?) S-10 Blazer. Later, I sold the Gov-Loc for $100 which was more than I paid for all the parts at the yard. Since the Auburn is a 2-series and the gears were 3-series, I needed to use a ring gear spacer. I got mine from Speedway along with a bearing kit. If your T/A and Cutlass are both the same series you won't need a spacer. Most of those bearing kits are listed as 1981 and newer. This is because one of the pinion bearings in the 1980 and older rearends is smaller. I had to buy one locally. There are write-ups online about setting up rear gears that explain the process better than I could.