[Malibu ss 64]

Have a reubild 12 bolt rear everything except the housing is new. New Eaton 3 series posi, Richmond 3.73 gears, Tom´s KA 30 splines c-clips axles and offcourse new bearings. How much horsepower will it hold up for? Know that I should have changed the ends to Ford style ends. Have another 12 bolt laying around to build up later. The car is a 3400 heavy chevelle 64 with aut. and 2500 in stall. The engine will be a 489 with at least 500 hp, not planing on slicks with this rear but who knows?

Marcus

 

[big gear head]

The 12 bolt is usually good to around 600 HP. You should be fine with it at 500 HP and the automatic.

 

[Malibu ss 64]

Thanks for the quick reply.

Marcus

 

[gnicholson]

My 3200 lb. 70 runs 9's with a 12 bolt

 

[Malibu ss 64]

My 3200 lb. 70 runs 9's with a 12 bolt

But not with c-clips 30 splines axles and Eaton Posi?

Marcus

 

[Nicks406]

Your setup sounds great and will handle 500+ with an automatic. Im sure a few people here can give you the limitation of some 12 bolts, but the worst I have seen was an axle tube bend at the housing - the spool and gearset were okay. It was in a 10.0's 68 Malibu. There has been one pinion gear breakage in my expirience but thats not because it was a 12 bolt, I'm guessing the gears may have had a defect.

 

[gnicholson]

No ,I have a spool ,bigger axles, ford bearings,steel caps, and a braced housing.I was just trying to tell you that the 12 bolt will take a lot of power properly modified. I think your combo is more than adequate for what you have.

 

[Malibu ss 64]

I forgott I also have a TA aluminium cover with studs for the posi bearingcaps, so you think it can handle some use even with slicks? Will build the other rear I have when money comes around .
Thanks

Marcus

 

[gnicholson]

the axles are the weak point and you replaced those.If you foot brake with slicks I dont see a problem.

 

[covertolds]

so you think it can handle some use even with slicks? .
Thanks

Marcus

You are really taking a big chance running slicks and c clip axles.

 

[Malibu ss 64]

You are really taking a big chance running slicks and c clip axles.

Life is a big chance . I know that the c-clip axles can break and ruin my quarters. But I won´t use it with slicks often just a few times/year, and will build up another 12 bolt with ford style ends and 33 splines bolt in axles and 1350 yoke, but then will the posi be the weak line? (going to change the spider gear in the one that I´ve already have) it´s a carbon clutch eaton posi a year old.

Marcus

 

[gnicholson]

The only way to find the absolute limit of a part is to push it to the limit. As long as you dont use a trans brake your not going to have a problem.You bought good quality axles,right. slicks and foot braking will not hurt it unless you got a hold of some bad parts.i.e. metalurgy, heat treat ,etc.

 

[covertolds]

As long as you dont use a trans brake your not going to have a problem.You bought good quality axles,right. slicks and foot braking will not hurt it unless you got a hold of some bad parts.i.e. metalurgy, heat treat ,etc.

Whatever.

 

[gnicholson]

Whatever what, instead of being an as#@*&% why don't you tell me where i'm wrong .I'm sure your much smarter with a ton more experience so lets here it. I've only been building differentials for 25 yrs. so I might be missing something.

 

[ToyzRMe]

I copied this reply that I posted in a previous thread so I didn't have to type so much.

I bought a set of Henry's Machine axles in 1973 to put in the 12 bolt in my 3450lb. '67 Camaro that had a 427, 4 speed, and 4.88 gears. The car ran mid 11's at 118 on slicks back in '73-'74. It was a stick car, and was launched at 6500-7000 on slicks. This car was my daily driver and street racer for years and had plenty of hard miles on it when I retired it in 1978.

The older guys should remember that, back then, the major aftermarket axle manufacturers were Summers Bros. and Henry's Machine.

These axles were standard length 30 spline axles with stock c-clips holding them in.

I ran the same pair of Henry's axles in various Nova and Camaro projects I built since that Camaro over the years and beat the snot out of all of them.

About 1992 or 1993, I sold them to a buddy that was building a street/strip '55 Chevy with a 468. He put a Camaro 12-bolt in it, and needed axles.

These same axles that I bought in 1973 have been in his '55 for the last 13 or 14 years of street driving and high 10/low 11 second passes at the track.

These axles have never EVER given 1 minute's problem, although he told me that the splines are FINALLY starting to wear a little bit. I think that could be expected after 33 years of hard use.

Remember, this pair are only the stock 30 spline with stock c-clips and bearings, so form your opinions from there.


Randy

 

[covertolds]

Whatever what, instead of being an as#@*&% why don't you tell me where i'm wrong .I'm sure your much smarter with a ton more experience so lets here it. I've only been building differentials for 25 yrs. so I might be missing something.

Geez, with your 25 years experience, you should know better than to say something as ridiculous as what you said. The guy said he has a car weighing 3400lbs. (assuming no driver), at least 500 hp, and a 2500 stall.

I sure wouldn't want to take the chances with a c clip axles and slicks. Stupid!!!

But hey, you seem to be very knowledged on the workings of a differential. I mean with 25 years experience and all.:thumbsup:

 

[betcha618]

Every car i get the first thing i do is a C-Clip eliminator. I don't think the C-Clip design is really good if you ever race at the track with slicks, and i think when you use slicks at the track you have to have C-clip eliminators.

 

[Nicks406]

I copied this reply that I posted in a previous thread so I didn't have to type so much.

I bought a set of Henry's Machine axles in 1973 to put in the 12 bolt in my 3450lb. '67 Camaro that had a 427, 4 speed, and 4.88 gears. The car ran mid 11's at 118 on slicks back in '73-'74. It was a stick car, and was launched at 6500-7000 on slicks. This car was my daily driver and street racer for years and had plenty of hard miles on it when I retired it in 1978.

The older guys should remember that, back then, the major aftermarket axle manufacturers were Summers Bros. and Henry's Machine.

These axles were standard length 30 spline axles with stock c-clips holding them in.

I ran the same pair of Henry's axles in various Nova and Camaro projects I built since that Camaro over the years and beat the snot out of all of them.

About 1992 or 1993, I sold them to a buddy that was building a street/strip '55 Chevy with a 468. He put a Camaro 12-bolt in it, and needed axles.

These same axles that I bought in 1973 have been in his '55 for the last 13 or 14 years of street driving and high 10/low 11 second passes at the track.

These axles have never EVER given 1 minute's problem, although he told me that the splines are FINALLY starting to wear a little bit. I think that could be expected after 33 years of hard use.

Remember, this pair are only the stock 30 spline with stock c-clips and bearings, so form your opinions from there.


Randy

I agree. C-clip elimnators are, to me, considered a rulebook saftey upgrade. The only stock axles I have seen shear/twist off at the splines are 55-64 GM 17 spline, 40 Buick axles, and some corvette stubs. Personally I have never seen a c-clip button "pop" off or a c-clip fall out or shred....maybe I am just lucky, but to me it's along the same lines as everyone who says all 400 sbc overheat. :bsflag:

There was a nifty test some rag did back in the early 70's with a chevelle or camaro, you know how it goes. Anywho, there rearend upgrade at the time was the GM Heavy Duty service pack spiders and side gears, a few more discs, and new GM axles. They ran the car into the mid 10's yanking the front wheels in the pics. I'll have to find it for the pictures alone!!


Again, your setup sounds perfectly fine for your combo. Post pics of the car and lets hope for one wheels up shot

 

[big gear head]

I built an 8.2 10 bolt with 28 spline Moser c clip axles. The car was a stock body '69 Camaro with a 383 and a 4 speed. I told the owner to take it easy on the rear end, but he didn't listen. He put slicks on it and raced it sevral times. The front wheels were in the air several times and the 28 spline c clip axles held up fine. The rear end is still in the car and working fine. I don't think a good after market 30 spline c clip axle is going to cause any trouble with an automatic transmission, street tires and 500 HP.

 

[gnicholson]

Thats what I was trying to say earlier.Iv'e seen a lot of people beat the hell out of the stock 12 and even 10 bolts without mishap in 11sec range st. cars. I think its a little risky but if you have a forged good quality c clip style 30 spline axle I think the risk is minimal ,but I may not have learned anything in 25 yrs. and am probably spewing stupid s#@*% again. Can I get an amen covertolds?