7.5 rear suggestions

[Bar50]

Buy two TH350 books. The HP Books one is $16 or so and an ATSG TH350 manual.

Do you have any tools? Do you have enough money to buy some tools? You can do a TH350 with minimal tools, but, the low/reverse spring compressor tool and the special snap ring pliers go along way. Have access to a press or arbor press? Punches and chisels? Part washer of some sort? Air compressor?

Do you know if there is an OTC, or WIT or some sort of transmission supply warehouse in Des Moines?

 

[64nailhead]

400HP on 7.5 or 7.625 will work woth street tires for a long time, but with sticky tires , a suspension built to launch, and a 3000+stall it's a time bomb. It's the shock load from launching hard that will destroy it. If that isn't in your plans, then you'll be fine. I migh have mentioned this before, but we ran a 7.5 with a used Torsen from a late 90's Camaro with S10 axles for a full season of spirited driving with drag radials.It also has a girdle. We were making 400+whp (not crank) and it looks like new inside. We also used a set of junkyard 3.42 gears.

You're cheapest way out (and functional) is to find a used Torsen - $150-200, a bearing kit - $80, and a set of Moser axles - $280 shipped.

The rear I described above is now our spare. We did upgrade to a GN 8.5, but went with a 31 spline clutch posi and Moser axles. But we're making well over 500whp now and figured the 7.5 with the Torsen wouldn't take it for long. Our car is daily driven (hard), and if we ever manage to break to the 8.5, then we can swap out the complete 7.5 in 3 or 4 hours and run it until we decide what to use next. Just have to use our heads when driving it. And FWIW, we have $1800 in the 8.5.

Someone posted that it is easier on the rear with taller gears - that is incorrect. A set of 2.29's will smash the axles or pinion gears long before a set 4.10's - it's simple phyics.

 

[SoFloG]

I was oblivious to the fact that I started this thread. Update. ..
After everybody's helpful input and the desire to build this car once correctly...

8.5" from an 85 442 should be arriving any day now thanks to Tony ELKMEANO. He says it's got 3.73's and is stock but doubts it being posi. I'm looking forward to cleaning it up and installing it.

 

[SupremeSpeed]

For a street car that you are not trying to hook up with or using slicks I see no issue putting a differential and gear in.
I ran my 7.5 with a Auburn differential and a 373 gear for 6 years behind a 600 horsepower 496 BBC and it never broke and I beat the crap out of it and later sold it for what I put into it when I finally upgraded to a 9" rear.
There is a member on here that twisted his new driveshaft and broke his new trans on a dyno and the 7.5 still survived.

I was getting a little worried. I took my stock 7.5 that came in my 88 Olds Cutlass Classic and had 3.73 installed in it. It's a Yukon with 3 year warranty, and the shop guaranteed me.

 

[MrSony]

I was oblivious to the fact that I started this thread. Update. ..
After everybody's helpful input and the desire to build this car once correctly...

8.5" from an 85 442 should be arriving any day now thanks to Tony ELKMEANO. He says it's got 3.73's and is stock but doubts it being posi. I'm looking forward to cleaning it up and installing it.

Hell yeah man, you finally got your situation sorted out even after all teh thread highjacking. Sorry bout that lol. And ain't too hard to change over to posi. New gaskets and bearings, maybe some different gears if you'd like, and the LSD of your choice. Good luck!

 

[SoFloG]

No sweat, thanks guys

 

[MrSony]

Buy two TH350 books. The HP Books one is $16 or so and an ATSG TH350 manual.

Do you have any tools? Do you have enough money to buy some tools? You can do a TH350 with minimal tools, but, the low/reverse spring compressor tool and the special snap ring pliers go along way. Have access to a press or arbor press? Punches and chisels? Part washer of some sort? Air compressor?

Do you know if there is an OTC, or WIT or some sort of transmission supply warehouse in Des Moines?

I do not have access to a press, but I could buy one or find one if need be. Why would I need one?

 

[SoFloG]

Some preview pics

 

[SoFloG]

Can anybody tell me more about it from those pictures? Thanks

 

[pontiacgp]

it's an 8.5 open carrier