lookin to do some upgrades on a sbc

[85 Cutlass Brougham]

If you are killing spider gears now, you will kill axleshafts next. A locker is not the answer to your problems, a stronger axle is. No 7.5 will put up with serious power and traction at the same time. You need an 8.5 from a Turbo car or 442 Cutlass at the least and maybe a 9 inch.
If the engine is a 71 or 72, it has 9:1 compression, maybe 9.5:1 and was rated at 330 hp factory. It should also have a solid cam in it unless it's a 73. I doubt it is stock internally as the engine is almost 40 years old and has likely been gone through once or thrice.

 

[illregal82]

lots of burnouts and stomping on the gas broke them i was told the exhaust pointing ant the rearend might have caused them to break sooner as well

 

[85t5mcss]

Something ain't right because mine gets 300HP/TQ thrown at it with no problems. I'm going 383 stroker next year with no plans of replacing the rear end. Unless u have slicks, u should be OK. The 7.5s are NOT junk, but they r weaker than lots of other rears. They can handle 450HP/TQ all day as long as the tires aren't grabbing (slicks or VHT).

 

[illregal82]

do you have a stock posi 7.5 . one was a stock v6 one was from a 79 malibu v8 and the other was the stock gp v8 rearend . i dont know he drove like a maniac though cause it hasnt broke my stock v6 7.5 yet so maybe it was him .

 

[85 Cutlass Brougham]

My engine makes about 350hp and 400+ft lbs of torque, sees a few burnouts here and there and gets shifted manually when driven in anger ( I HATE large SUV's ,trucks and luxury cars that think they're fast!:lol🙂 plus it barks 2nd gear in an automatic upshift and I have yet to break one. I have no limited slip as of yet, but the 3 series Gov Lock posi I have from a MCSS does not inspire confidence in me. They are not known for longevity under severe duty useage, and I plan quite a few trips to the local 1/8 mile track in the near future. I can use no more than 1/4 throttle up to 15 mph or it just boils the tire ( one legger!). Were it to hook it would break.I would go with an 8.5 in my car if I could find one and had the money available to me when I found one. It is the rearend found in most 2g F cars, and is more than up to your engine driven on the street. It also uses a better posi than the Gov Lock and the 2g F cars used either a cone or clutch style posi unit, so it is junkyardable if you get one with an open carrier. If I could fit a Ford 8.8, I would use that too over a 7.5. (Anyone ever try?) At any rate, if you drive the car hard regularly, you will need a better rear end.

 

[illregal82]

my goal is to be able to humilate a 300c or charger i cant stand them everyone thinks there so fast i have driven one hard its fast but it does not look like a bentley it looks like a silly *ss 300 . theres this guy thats says he will put any amount on his stock charger . i could catch one and keep up but i cant take off as fast .

 

[illregal82]

got my check today looks like ill have 1500 at most to spend going to look at a aluminum radiator and quicksilver shifter right now