12 bolt ring & pinion in '67 housing?

cocobolo

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Hope I have this in the right section...?

I bought a '67 'Vette IRS complete and it's going in a '35 Chevy. The plan is for an LS3, 4L70E in front of it.

Original car weight is 2,600 lbs, and hoping to keep the finished project below 2,750 lbs.

My several questions go like this:

1. If I don't beat the heck out of it will the rear end stand a chance?

2. I read recently (can't find the article now, of course) that it is possible to put a 12 bolt ring and pinion into the older housing with some modification. I haven't got the actual rear end in the garage yet, picking it up in the next few days, but I'm told that it could be a 10 bolt. Does anyone know if that's correct?

3. Going through many of the threads here, I'm now wondering if an aluminum unit might be beneficial. I am concerned about weight - aren't we all - but not to the point of absolute lunacy. I'm more concerned about whether or not the rear end will take a steady pull from the LS3.

Lots more questions later as I get into it, I'm sure!
 
Saw a guy who once used c4 vette front and rear suspension on one of those. I wouldn't use a c2-c3 rear suspension when a c4 is a lot better for both weight and handling.

Just find a c4 dana4
 
later shark vette rears are notoriously weak with the aluminum pumpkin....

the iron diffys are the way to fly, I THINK it's possible to put a 12 bolt in there, with some case grinding, and lord knows what else....Gary GTR999...is the one to talk to, send him a PM from here so he notices this thread....


:D:crutches:
 
Saw a guy who once used c4 vette front and rear suspension on one of those. I wouldn't use a c2-c3 rear suspension when a c4 is a lot better for both weight and handling.

Just find a c4 dana4

Thank you for that. I'm going to put a Heidt's IFS in the car for a couple of reasons.

It looks really good, and they have one specifically for the good old '35. Very simple weld-in setup.

I can always use the '67 for a lighter project. There's a possible T-bucket in the far off future.
 
later shark vette rears are notoriously weak with the aluminum pumpkin....

the iron diffys are the way to fly, I THINK it's possible to put a 12 bolt in there, with some case grinding, and lord knows what else....Gary GTR999...is the one to talk to, send him a PM from here so he notices this thread....


:D:crutches:

OK, thanks for that. I'll shoot him a pm.

I did read about the grinding part, but there was little else of real value in the short article I read.

Wasn't aware that the aluminum pumpkins were so weak.

The current plan is for the 525 h.p. EFI LS3, but I'm going to buy the package later in case GM comes out with even a better one.
 
I just PM you back.
The iron diff with 12 bolt, done correctly, with hold up to 700hp with 1350's and 1000 with 1480 axles. All the parts you can get directly from Tom if he won't ship to Cn I can for you.

You have to be sure you have the 67-79 housing to start with because it is the wider housing and you don't want to use the 63-66 for a 12 bolt. You going to have to check the overall width too, I don't know how that will work in a non vette but you should check it.

You will need a mill, lathe, surface grinder, press and good measurement tools.
You can read up on my threads here and on DC on this build there are plenty of pictures.

Good luck.

Gary
 
Gary...many thanks for your PM and all the information.

I shall read your suggested material to see that I do (or do not) have the correct housing. Will be here in just a few days.

Again...many thanks.
 
You will need a mill, lathe, surface grinder, press and good measurement tools.
You can read up on my threads here and on DC on this build there are plenty of pictures.

Good luck.

Gary

I was in Tom's Bellflower shop, maybe a month or so before he moved to Idaho. I watched as he explained to a potential customer why he, the customer, should not attempt the 12 bolt conversion. My limited experience with Tom is that he doesn't have patience for the unknowing, particularly if they're trying to "save" money. He was very polite explaining all the in's and out's to the potential customer. He explained that most likely a new person would screw things up. Not to be too harsh, he explained that when starting out he had also screwed up things also...it's all the part of the learning experience. I've always enjoyed my experiences with Tom and also his wife who also can be there. Of course, we all remember Kenny, Tom's associate who was really the driving force behind a lot of his Corvette bullet proof stuff. Kenny died of a heart attack at about 55.
...............
PS. A local transmission/differential repair business had ordered several pallets of transmission/differential parts from Tom. All of the pallets were in the front of his Bellflower business..once again. not to much before he left California. An employee of the purchaser showed up, while I was there, and said that his boss had a change in mind, he didn't want to buy all the parts originally ordered...only a part of the original order. Tom's response was that all the parts had to be accepted, or none. And if none, he would never sell parts again to that purchaser. A flurry of cell phone calls...All the originally ordered parts were bought.
 
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