Hey you guys, I got a quick questions of all of you. I want to know how much horse power and torque a stock 91 rear end can handle. If anyone has build up there car with a stock rear end, did it work out or was it unable to handle the power/ torque. I am close to completing the build of my 383. I just want know how long my rear end will last.

 

477HP and 391 ft/lbs torque

 

is that for general 3rd gen rears or just for that particular year? i have an 83 and was thinking about swapping a 4th gen because i thought iw would be stronger and would upgrade my brakes. 4th gen rears about that same?--->477HP and 391 ft/lbs torque

 

its either a number be pulled out of his ***, or its what his car is making, either way, thats all it is, a number.


horsepower and torque really srnt what kills the rear, wheel hop and traction are what does it. So a stock 3rd gen with a 305 can break the rear if it wheel hope bad enough then grabs.

ultimately its a crapshoot. No way to give you a real number. Like i said its all about traction and wheel hop

 

I pushed one well into the 11 second range before finally swapping in a 9". It was basically stock with the typical beef up improvements.

As mentioned above, there is no magic number. They're survived on the dragstrip behind BBC engines and have broken on the street with low HP street engines. No matter what you try to do to it to beef it up, it will still have a tiny ring and pinion. Breaking the teeth off is the #1 failure.

 

So in short, you might get away with it for awhile but it is what it is. Don't waste any money thinking you're going to make it stronger.

Dan

 

I read in a hot rod article of a budget build up of a thirdgen with a 7 1/2" rear end. They said that it would handle 400ft lbs of torque safely. They said running this kind of power safely you should inspect or replace all bearings make sure you pinion backlash is within spec and install a T/A style diff cover which preloads the main caps in hopes of preventing deflection under highloads(jegs makes one too i run one in mine). As stated earlier the weak link is the gears so they also said not to run any steeper than a 3.73 ratio the smaller the pinion the less the teeth engagment is. Lastly no hard lauches with Slicks

 

Sort of defeats the purpose of a high HP engine.

 

well im not running slicks or anythign like that. some nice streets and will be replacing all the suspension. i will be running and built 355. i just cant afford to replace the rear and the trans at the same time. its a non wc 5 speed which i all ready know wont hold up. dont know how it held up with the 350 that was in the car to begin with.

 

Seen a stock 6 speed 2002 firehawk w/ 315 drag radials and a 4k launch blow his. Was running 13.40's (5500' elevation). I was running mine for years w a 383 and procharger (14lbs boost) with no slicks or hard launches. I have seen a buddy w/ a one legger Z28 knock off a 12.50 lol.