I have a 383 engine making about 435 hp and 450ftlbs of torque Will the 7.5 rear end live? The previous owner put aftermarket axles and a posi in it. I want to put some stickies on it and do some drag racing with it. How do you know for sure if it is a 7.5 rear end. The cover is oval.
7.5 will it make it?
- Thread starter 383 malibu
- Start date
it should be fine, this site will show the difference in rears.
http://www.oldsmobility.com/10bolt-tech.htm
http://www.oldsmobility.com/10bolt-tech.htm
Im one of the very few on here that think the 7.5 has a bad reputation , its not as week as some say. Evey one has there owne opinions and experiences. With that said IMO it will NOT take to many hard launches with slicks [-X .
I have a 3500 stall converter and will launch off the foot brake. Is this considered a hard launch? What usually breaks on them?
I've been launching with stickies(1.58-1.62 60 foots) for four seasons with a 7.5. My 389 makes about 400 hp and 450 lb-ft and I footbrake with a 3000 convertor. The weak links are stock axles, small spider gears and the carrier saddles not being able to retain the carrier under high torque situations. Hopefully the aftermarket axles and posi the previous owner installed are 28 spline. Aftermarket 26 spline axles are not much better than stock. The different types of posi units have various torque capabilities. Any chance you can get more info from him? A support cover will help keep the case from distorting as well as keeping the carrier in place and therefore the gear mesh contact area intact.
I went through two ring and pinions, one axle, one posi, and a mini spool in two years of racing the 7.5 in my El Camino. The motor was only a hydraulic cammed 283 running 8.0s in the 1/8th. 70 Monte Carlo 12 bolt is in there now with 406 motor (10" rim, 6.5" backspace, 1/8" spacer, 30x9 Hoosiers, no notch)
Good luck if you choose to keep the 7.5. Start shopping for a 12 bolt.
Good luck if you choose to keep the 7.5. Start shopping for a 12 bolt.
Mike Allred said:
no offence meant here, but using your situation as an example...if you add up the cost of the parts you had to replace to keep the 7.5 alive, you'd have the majority of a stronger rearend paid for. the first time i broke an axle, i refused to put any more money into the 7.5 and found a deal on an 8.5 that was already built.
I have been running mine for about 10 years now with a 3.73 gear and a Auburn Posi. My 406 make 439 hp and 437 tq at the wheels. I use 28x12.5x15 Mickey E.T's with it. I launch about 2000 rpm and a 3000 stall converter on the foot. I think it will hold just fine with your combo. I don't see why people always down it. I guess me and my buddy are an exception to the rule. His is a SS Monte with a 383 and the same set up in the rear as mine with stock axels also pulls the front tires up about a foot and carries them about 10 feet or so and runs a 11.20 e.t. So, you be the judge of that. If he replaced the axels already then I think you will be fine.
