stock class rear axle?
 

I am considering stock class racing my 56 Chevy, [again] after many years. does the rule book still say you have to run a corporate rear axle? I do ,not want a 12 bolt.

can I use a '55-'64 style center with different bearing ends and race axles? also can the tubes be shortened[just a little]?
thanks Rod min AZ

Re: stock class rear axle?
 

Yes and No

Re: stock class rear axle?
 

Rod, you could use a 57 -64 Pontiac/ Olds rearend housing if you wanted to retain the stock look. It is not legal to make the stock rearend narrower plus the tires will be up against the springs if you do. A cheaper alternative is finding a 8.5 out of a Camaro or Firebird. Just as strong as a 12 bolt, but not as many ratio options.

Re: stock class rear axle?
 

Better reconsider the 12 bolt ,with Pro gears, if it's going to be a stick car.

Pontiac/ Olds not legal in Stock

Re: stock class rear axle?
 

X2 What Mark said

Re: stock class rear axle?
 

The Olds/Pontiac rear is not acceptable for a Stocker trifive......I asked.

Re: stock class rear axle?
 

Why?

Re: stock class rear axle?
 

REAR END Original rear end may be replaced with another from the same automobile manufacturer; truck rear end prohibited. Aluminum center section permitted only on vehicles that were originally equipped with same. Distance between backing plates may not be changed. Any gear ratio that fits third-member case or housing permitted. Limited-slip or ratchet-type rear ends permitted.

So a COPO comes with a 9" Ford so I guess a 9" Ford is now legal?

Jim Mantle V/SA 6632

Re: stock class rear axle?
 

Often wondered about that Jim.

Re: stock class rear axle?
 

What Jim said. Tech Director said, must be Chevrolet.
And a big no on the 9". Asked about that one last year.

Re: stock class rear axle?
 

9 inch only on COPO -Cobra Jet and Drag pac is the way I understand it--I think NHRA had a post on what vehicles can use a 9 inch-FED 387

Re: stock class rear axle?
 

modern parts in 12 bolt will be great in there....
pro gear absolutely a must with ANY stick even a W car..... and correctly setup if it isn't you won't get a season out of it... Randall was going through a set of gears a season on his truck... I set them up and he has 6 years on them now...
knock on wood…. I have never hurt a gear or anything in my K/S car... gear has at least 300 runs.... spool, steel caps, 35 spline axle, chrome moly tubes,5/8 wheel studs all Mark Williams parts, I installed the tubes and caps and built the rest...

Re: stock class rear axle?
 

A 9 inch is legal in any 2008 and newer car.

Re: stock class rear axle?
 

Saw a 69 Camaro Stocker a few years ago with a 57-64 Pontiac r end in it at a Div. 3 Points race after any GM rearends were oked. They must have changed the ruling. Ford rearends are ok in certain years though????

Re: stock class rear axle?
 

Last I knew Olds was still General Motors.

Re: stock class rear axle?
 

That’s what I was thinking. ....Are you positively sure of that YAK ?

Re: stock class rear axle?
 

Doesn't make sense considering I was told I could run an 8 3/4 Mopar or a Dana 60 in an AMC (which I thought was a stretch).

Jim Mantle V/SA 6632

Re: stock class rear axle?
 

What I am sure of is lots of Jr. Stockers would have loved to use a P/O rear, but instead, they went through untold grief with Chevy "P" cases and all that junk.
The Pontiac/ Olds setup was common in the M/P and Gas classes.
If the rulebook still says "of the same manufacturer" , NHRA always took that to mean Chevy, one , Pontiac ,two , and different.
Now, if it says something about "corporate" , then you boys may have an argument.
But then again, it seems they have already spoken on this, many years ago.

Re: stock class rear axle?
 

Email from Tech Director 1/29/2020:

You are not allowed to use any rear end housing under your car other than a Chevrolet housing. It can be a 10 bolt, 12 bolt etc., but must be a Chevy housing.

Re: stock class rear axle?
 

There you go, Thank You for the clarification Mr X.......

Re: stock class rear axle?
 

Often wondered why no truck rearend?

Re: stock class rear axle?
 

Once AMC was bought by Chrysler it opened up all those engines and rearends to be used in AMC cars. Wasn't a Dana 60 used as OEM in the Super Stock AMX .

Re: stock class rear axle?
 

IIRC SS AMXs used the AMC 20 axle with Henry's axles.

Re: stock class rear axle?
 

Somehow I have trouble understanding how NHRA considers a 56 Chevrolet to be "less" of a GM product than a 57 Pontiac, compared to an 60s or 70s AMC car is to a Chrysler product, after AMC was bought out by Chrysler in the 80s! :confused:

Re: stock class rear axle?
 

GM is not the manufacturer, Chevrolet is.

Re: stock class rear axle?
 

I have looked at a lot of center sections of the rear ends in lots of brands and I see GM cast into the casting not Chevrolet or the other GM brands.
Just My Take
Rick Cates
Canyon, TX

Re: stock class rear axle?
 

If the previous statement is true, there are a lot of BOP and Cads out there with 12 bolts. Travis may be able to chime in on this. Or are all those cars not legal?

Re: stock class rear axle?
 

I understand the perspective, but consider that the corporate structure of GM related to the different manufacturer brands is different from the other corporations and their brands. Chevrolet, Pontiac, Oldsmobile, etc. were all considered to be totally separate entities since they all started independently and then brought under the umbrella of GM. Ford and Chrysler both created all their brands from top-down decisions. The brands of GM chose to be part of the consolidated group to work together, but not to be controlled by the GM corporate office. As a result, most of the design and manufacturing up until the late 70s was done independently from each other. The rule says "of the same manufacturer' not "the same corporation".

Re: stock class rear axle?
 

Re: stock class rear axle?
 

I know for a fact that the 1970 GTO with the 455 engine option came with a 12 bolt. It is also a fact that some Buick Skylarks built in 1970 had them.

Re: stock class rear axle?
 

Don, I guess you are saying that at least one Cad had a 12 bolt. ;-) A lot ? Doubtful..some of the other 2-3 had 8.5's.

B-O-P are all covered for 12 bolts in the 70-72 era.

Re: stock class rear axle?
 

Here's something to think about on Chevy rear ends:

-Some '82 Camaro's came with the Spicer (Dana) 44 rear axle.
-So a Spicer/Dana rear axle would be a 'Chevrolet' rear end.
-So if a Spicer/Dana is a 'Chevrolet' rear end (and we just proved it is ;))
-You should be able to legally use, oh...let's say...a Spicer/Dana 60 in any Chevrolet stocker.

I rest my case. :) -Al

Re: stock class rear axle?
 

Alan, that might be a tough sell but yes, GM offered a Dana 44 rear as a "service package" replacement for an early 80s Camaro/Firebird with the 305 HO engine. Contrary to the NHRA Guide, the 305 HO was a stick only combo and they were constantly breaking the 7.5s. I have never nor do I know of anyone who has ever bought one over-the-counter but they were the replacement for warranty claims. I've had a couple of them over the years.

Re: stock class rear axle?
 

I believe that the Dana 44 was factory installed in the early 1LE cars.

Re: stock class rear axle?
 

Correct! :) -Al

Re: stock class rear axle?
 

Jeeps also used Dana 44 drive axle differentials.....I think AMC also used them. Chrysler owns Jeep....You do the politics.:rolleyes:

Regards,
HB2:)
Dissident

Re: stock class rear axle?
 

[QUOTE=Billy Nees;613757 Contrary to the NHRA Guide, the 305 HO was a stick only combo .[/QUOTE]

Say it ain’t so ..Billy.....

Re: stock class rear axle?
 

This is an assembly line installed Dana/Spicer 44 rear in an '82 Z28:

https://i.imgur.com/ORcrkjtl.jpg

But back to Rod's question...why wouldn't you want to run a 12 bolt? -Al

Re: stock class rear axle?
 

I remember the 1983 being stick only, but not sure on the other HO years. Maybe some folks out there would have to convert to a stickshift?

I recall NHRA pulling back the Baby LT combo to automatic only so it isn’t out of reach for NHRA to correct that 305 HO spec to stick only if warranted. ( I don’t know for sure either)

Re: stock class rear axle?
 

Well, I stand corrected.