Now that I have your attention, its not what you think. I bought my gf a 86 cutlass to run a beginner class at my local dragstrip. Im tired of her bugging me to run my car!!!!! :af: Its a stock 86 cutlass with a buick 455 in it. Its just a mild cam car and im guessing its gonna run 13's????? What can i do to the stock 10 bolt to make it strong enough to be a safe car for her? Or is there a rearend out there that I can bolt right into this car from another car like a chevelle or skylark? I run a Ford in my car and never had to mess with my stock rearend before. Any help is appreciated,:beer Tony My car 81 Olds Cutlass / Buick 455 Powered Her car 86 Olds Cutlass / Buick 455 Powered
An 8.5 rear from a Grand National or 442 will bolt in. You may need a different driveshaft depending on which trans is in the car now.
I went 12.90 i my monte carlo with a 7.5 rear but i don't think it would have lasted in my car.I went to a 12bolt from a 68-72 chevelle with custom upper arms.
...Tony; You-The-Man!!! :grin: Good-One regarding the thread title ... I knew exactly where you were going with that (LOL). I had a 8.5" rear from a g-body Olds442 with the camed-Olds307 ... and "GN" posi rear. The rear on the g-body Olds442/Olds442-Hurst ALL came with a 3:73 gear ratio ... and NOT all were posi units. Mine was posi/3:73. On that .030-over Regal455 (built by Scotty :grin: of Pee Gee Buick when he was in Brooklyn, NY), I had the factory intake/exhaust, a TH400 3-speed automatic for $75 from the junkyard, 2-1/2" true duals ending at the axles (like my Stage-1 Regal now), and the Olds442 "GN" posi w/3:73's. That 10:1-455 Regal had a Lunati 501-lift cam (I had factory 1:55 rockers ... like now) ... and the BUICK SURE DID BOOGIE!!! It chirped 2nd @ 4400-rpm and banged 2nd HARD! I would take my Daughter's Uncle for a ride in it just to shift into second watching the Buick JERK HIS 350+ LBS BACK INTO THE SEAT HARD. :grin: He LOVED-IT! The 3:73's I felt were great ... UNTIL I ran out of steam against a 1999(?) Chevy Camaro "full of passengers" on the Grand Central Expressway one late night. I saw the Camaro coming ... I slowed to 3500-rpm (as Scotty told me to) ... the Camaro was at my bumper ... I took the motor to 5200-rpm immediately ... AND THE CAMARO KEPT COMING, PASSED MY ASS, AND RAN AND LEFT ME FOR 7-CARS!!! He couldn't make anymore distance from me, and I couldn't close on him either. THAT BURNED-ME-UP! :rant: I was later told that the 3:73's were too much gearing for my combo. I now have 3:42's, a "convertor", headers, intake, and a bigger cam. In closing ... I "feel" the 3:73's are GREAT for your Girlfriend's Olds/Buick455. One advantage the g-body Regal has over the g-body Olds is the body's rear fender wells; the REGAL can take a WIDER tire all day in stock form. Also ... isn't the g-body Olds @ 200-pounds LIGHTER than the g-body Regal?????? :grin: :kodak:
A GN rear will have 3.42 gears. May or may not be posi. As far as tire size, with a 4.5 or 4.75 backspace wheel, I think you can stuff a 295 in there. Don't know how tall you can go.
Correcto' :TU: Also, a 295 "will" go on easily ... but it will stick out of the fender wells @ 2-inches ... like on Ralphy's Regal in my neighborhood. I suggest the 275's. :3gears:
Hey, Tony. Here are photos I took today of Ralphy's Regal with the 295-tires. They don't look that wide in these photos. Hope this helps. :grin:
Check the rear end 'pumkin' for the 90 degree "corners" on both sides at bottom just like 71-72 Skylark/ gs rears. These were ONLY under the Buick Turbo cars 84-87, and MOST of the HURST_OLDS;That is the KEY to it being 8+1/2 inch rear.The usualrun of the mill G-body and A-body 7+1/2 rears have 45 degree "ears" or "points" on those locations. Monte SS and SOME of the Olds Cutlass rear was 7+5/8 AKA 7.625 gears in the 7+1/2 housings. Wheels are same on all rears, as width is same. Posi axles last letter of code FROM FACTORY is in upper half of alphabet , usually have iron drums. Key word is FACTORY. Most aluminum drums have been swapped out from wear, or added to reduce weight. look for a green paint slash in the hub of the driver side. Easy reminder: Green is great, P is POSI
Tony,you don't need a picture,The ears sticking out on the bottom of the rear[on the sides]the 7.5 comes out into a point,the 8.5 is almost square,about one inch wide.BrunoD.