ok my rear end finally gave out.. some how 9 teeth on the pinion gear were broke off. when i pulled the cover i only found 2 of the teeth so either they were chewed up or already broken when i got the car and finally the two that broke made it give away. so anyways i found the numbers on the gears and i think if i remember right they were 14 and 41 which is a 2.23 gear.. what gears do i need to go with? when ilook in jegs they show different 10 bolts so which one do i go with? this rear end came out of a 84 f body i think.. my car is an 88.. so any help would be great part numbers or something.. i want to go with 3.73 or 3.55 which do u guys think?? thanks for any or all the help u guys give thanks!!!!!!!!!

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO factory fiberglass wing black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft best 1/4 mile run of 13.77 @ 102.07 with a 1.9 60' THE FORMULA IS FOR SALE SO ANYONE INTERESTED IN PICS OR PRICE EMAIL ME.. HAVE TO SELL IT GOING TO BUY A HOUSE.. IT SUCKS BUT HEY GOTTA DO WHAT YA GOTTA DO
also 1997 grand prix gtp black with custom cold air indcution... its the girl friends and i havent got to run it at the track yet but i will!!! yes i will... well as soon as she lets me lol.. but it seems pretty quick for a 6 and front wheel drive

 

I come up with an odd 2.93 ratio with 14-41 gears, I would go with 3.73's. They will give you a 5100 trap rpm at 104 mph with an automatic in third gear without converter locked up(1:1). Thats 3.73x355x104mph divided by 27"tire=5100rpm.
You need gears for either a 7.5 (7 1/2) or a 7.625 (7 5/8) They interchange as far as I know.

 

yeah i think u are right i was wrong on the numbers but i know it divided up to 3.23 so is that a 3 series or 2 series? if its 3 i see jegs has a gear kit with 3.73 and and install kit for around 3 hundred or so.. well thanks..

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO factory fiberglass wing black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft best 1/4 mile run of 13.77 @ 102.07 with a 1.9 60' THE FORMULA IS FOR SALE SO ANYONE INTERESTED IN PICS OR PRICE EMAIL ME.. HAVE TO SELL IT GOING TO BUY A HOUSE.. IT SUCKS BUT HEY GOTTA DO WHAT YA GOTTA DO
also 1997 grand prix gtp black with custom cold air indcution... its the girl friends and i havent got to run it at the track yet but i will!!! yes i will... well as soon as she lets me lol.. but it seems pretty quick for a 6 and front wheel drive

 

I'm not sure what series it is but I got an Auburn posi for a 7 1/2 GM rear and it said for use with 3.23 and up gears. The tech people should be able to help you when you order.

 

If you had a 2.93 gear set before, I'd say you have a 2 series carrier.

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"I know why you want to hate me, cause hate is all the world can seem to see lately....." L.B.

 

the gears that are in it are 3.23 so that is a 3 series right?? just want to make sure..
has anyone bought that kit from jegs? the one that comes with the gears and install kit? what all comes with that kit? shims? and hopefully everything to make it work> thanks for all the help guys

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO factory fiberglass wing black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft best 1/4 mile run of 13.77 @ 102.07 with a 1.9 60' THE FORMULA IS FOR SALE SO ANYONE INTERESTED IN PICS OR PRICE EMAIL ME.. HAVE TO SELL IT GOING TO BUY A HOUSE.. IT SUCKS BUT HEY GOTTA DO WHAT YA GOTTA DO
also 1997 grand prix gtp black with custom cold air indcution... its the girl friends and i havent got to run it at the track yet but i will!!! yes i will... well as soon as she lets me lol.. but it seems pretty quick for a 6 and front wheel drive

 

2.93 odd? Who you calling odd?

If you have 13/42 teeth, you have 3.23. BUT, you may not have a 3-series carrier if the gears were put in by a former owner - 3.23 gears are available for 2-series carriers.

If the axle code says you should have 3.23 gears and you have the 13/42 teeth, then it's a fair bet that you've got a 3-series carrier.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. Cat-back from '91 GTA, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker headers & y-pipe, 3" Catco cat & 3" cat-back).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Edelbrock 1901 Q-Jet, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

 

yeah 5.7kid the numbers do divide to make 3.23 what ever number i said before i was off by one on each.. also does anyone know if i am supposed to put limited slip diff fluid in the rear end or not? thanks for all the help. started tearing into her tonight what a pain!! but it should be well worth it i hope!!

 

i got 3.73s and i love em, much better than the old 3.45`s i had (oh and the 3.45`s were in my old 9-bolt)which is now broken

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87 IROC-z 305 TPI 5spd 10-bolt 3.73 posi ,8.8 Accel wires , bosch platinum +4 plugs,MAF sensor screens removed, gutted air box, ram air, K&N air filters,TB coolant bypass ,polyurethane tranny and torque arm mounts, K&N oil filter,Mobil 1 synthetic oil 20w50, futura GLS super sport tires 265/50/15 rear and 235/60/15 front mounted on 86 monte carlo SS rims ,

400 sbc and a 6 spd in the works