[J.C.you]

I have made a few 6000+rpm launches with my big pontiac rear in my 66 goat. 3400+lbs. Smooth as silk, so far. I bought this rear from a guy that ran it in a 7.90 outlaw street 70 camaro. Not sure about the weight of the camaro, but it had to be at least 3300lbs. Funny thing about the deal, is he put a tricked out fab 9 in his car with NO other changes and his car slowed down!

You may consider putting a brace on each side of the front ribs of the centersection to the front of the axle tubes. Like the braces offered for 8.8 ford rear. I have considered doing the braces on my big pontiac in my goat.

[SupergasDil]

Bill Eveland, I was wondering about this the other evening. The scan is so small though I cannot read it. Can you fax it to me 918-497-9756

George, I have bought a few sets of gears and was thinking that the set in the GTO was a new set but once Bill 500 plus jogged my memory I remembered that I put these in the car when I first pro streeted it even before the first blower set up. So they have seen a lot of street miles, mild nitrous, street blower, back to racing, and now the heavy duty set up. About 10 years of abuse.

Last night my neighbor came over who is a pipeline engineer, inspector. I'll save the details but basically he said he could see lots of stress cracks on the pinion (every tooth) as well as a tooth that was stressed, and how much it gave before it snapped off. He said the case was obviously a clean break and was forced away from the housing. It was hard for him to tell any detail about the ring gear as it is still in the rear but there is a section with the teeth still in tact and 1 is missing in the middle. Then 3 teeth later the carnage starts.

Brian, You are absolutely right about the clutches and tire frying. I didn't think about that. Those guys weren't planting all of the power in a instant like we are now.

There are a lot of us in high horsepower mode with the need for speed and a lot of us are boosting wanting more and more. It's addicting. I just found the weak link- GEARS-
and that broken $400.00 set will now cost a minimum of about $1,100.00 if I go back with the same set up. That includes another driveshaft that got wasted too.

If I switch the entire set up to a 9" it's about $3,500 with me doing all of the welding.

George, what rear end are you running and did you put another set of street gears in ?

This may be a deal where we need to replace the gears every year to be on the safe side. There is a lot more maintenance when you step up the game.

JC I don't know if the added ribs would have helped in this case. I think everything is mounted pretty solid already.

I am glad to hear that a lot of you are running the big Pontiac rear with success.

[GTOGEORGE]

Dil,
Hows it going?

I have a Dana 60 (came with the car).

I just finish installing 3.73 street gears (Dana/Spicer) back in ..............I didn't have a choice that all they make in a 3.73 ratio.

Yes Dil we are making a awful lot of TORQUE with these Root Blower engines but what a rush!


GTO George

[Silver Judge]

That is some serious CARNAGE


Scribner Welding makes some seriously stout rear ends for some west coast racers

http://www.scribnerwelding.com/photos.html

[SupergasDil]

I just got off the phone with the tech dept at Richmond. No luck on cutting a set or 2 of pro gears for our rear ends. They said they would do a run for us for 25 but they would all need to be the same cut. I don't see that happening.

A few things,,,, he said that there are a lot of guys running this rear set up because the 9.3 is a big strong gear, even in the street gear, but obviously more brittle. He said we would probably get a little more life with the pro gear but it honestly needs to be checked/ changed because the softer material wears faster.

He said at our power level we wouldn't get 500 runs but should be fine with 100.

Whatever rear end we end up using,,,,I will be pulling it apart for regular maintenance. now.

[Bill Eveland]

Thats the largest scan I had Dil, I resized them some but they will be a bit blurry. As you can tell this is an old article from the lack of website addresses on the ads...

[Scott M]

The shortcomings of the Olds/Pontiac rear are why Rick Johnson switched to a 9" Ford over 15 years ago. He had the same thing happen to him.

Top Fuel cars of the 60s used this rear, sure, but they also had 7-9" tires.

How much for the housing and stuff, pictured above?

Might be nice for a street car I have planned.

Thanks.

[500plus]

I have located a fab shop here in Tulsa that will do the 9" conversion on our Olds/Pontiac housings for $100. He is familiar with this procedure and has been running a 41 gasser for years. Cool!!

[J.C.you]

Originally Posted by SupergasDil

I just got off the phone with the tech dept at Richmond. No luck on cutting a set or 2 of pro gears for our rear ends. They said they would do a run for us for 25 but they would all need to be the same cut. I don't see that happening.

A few things,,,, he said that there are a lot of guys running this rear set up because the 9.3 is a big strong gear, even in the street gear, but obviously more brittle. He said we would probably get a little more life with the pro gear but it honestly needs to be checked/ changed because the softer material wears faster.

He said at our power level we wouldn't get 500 runs but should be fine with 100.

Whatever rear end we end up using,,,,I will be pulling it apart for regular maintenance. now.

Who is the guy in texas that deals with pontiac 9.3 stuff? He may be interested in doing the 25 sets. I would be in for a couple of sets.

Looking alittle closer at the pic you posted, i noticed a dark streak or spot on the pass side of what is left in the housing. Is that a camera illusion or could it have been cracked there already?

[ponchospidel]

i leave at 3900rpm off the trannybrake, gears are gm 3.90's i have mark williams billet caps on both sides with a spool and moshier axles. car weighs 3585 race weight and with the 29.5/10.5 slicks it normaly 60's 1.30-1.32. as far as power it made 939rwhp and has run a best of [email protected] in the 1/8.
i have never seen one break like yours did.

[hurryinhoosier62]

Dil,
Was the carrier magnafluxed? I agree a broken tooth is probably the cause,but a little
NDT goes a long way. Man,that SUCKS!!

[Scott M]

Originally Posted by J.C.you

Who is the guy in texas that deals with pontiac 9.3 stuff? He may be interested in doing the 25 sets. I would be in for a couple of sets.

Brad Duerst.

http://www.fabcraftmetalworks.com/

He simply buys his gears from Richmond.

[rod cole]

Are pro gears a different metal or heat treat? I would think you could have them heat treated to a different spec (softer). Then froze to stabilize them. Rod

[SupergasDil]

Yes, Pro Gears are a different metal composition and heat treat. According to the Tech at Richmond, they are designed to take more horsepower and harder hits. The teeth are made to flex and give without snapping. Whereas the street gears are made to last with a stiffer material. Once they start to flex, they crack, then break.

[500plus]

Just dropped off the housing out of the funny and my 40 spline axles and carrier out of the streeter to get the ford transplant done. Should be about $300 total with shortening and resplining the axles. I will post pics when completed in about 2 weeks.
Now to decide on what gear ratio for this, stay with a 3.89 or what? I tried the calculator from richmond gear and it is suggesting a 3.42 or 3.54 depending on rpm. The one from mark williams is stating with the 3.89 top mph will be 172. Basing this on 1200hp, 2300# car, 6800rpm and 33" tall tires...btw what is the appx growth factor for goodyear slicks with a d6 compound?

[hurryinhoosier62]

Dil,
Have you ever considered having the gearset cryo-treated. It SOP in the NASCAR and SCCA ranks to extend gear life.

[2SlowTA]

Originally Posted by 500plus

I have located a fab shop here in Tulsa that will do the 9" conversion on our Olds/Pontiac housings for $100. He is familiar with this procedure and has been running a 41 gasser for years. Cool!!

I don't need this right now, but would love the name of a good local fab shop that is familiar with our stuff to add to my list. Can you post it or send a PM?

[500plus]

Originally Posted by 2SlowTA

I don't need this right now, but would love the name of a good local fab shop that is familiar with our stuff to add to my list. Can you post it or send a PM?

Chuck @ CW Auto Fab 918-231-7857 is gonna do the rear and Rodney @ D&R Fab 918-663-2590 will be making the zoomies

[SupergasDil]

I picked up my rear end housing from Chuck at CW Auto Fab tonight. He did the Mods to my "61" rear end housing like the article that Bill Eveland posted. This is an AWESOME deal. The new Ford 40 spline spool with pro gear center section should be here Wednesday. I'll post some pics tomorrow. $200.00 for the mod. Waaaaay cheaper than buying a whole new housing and brackets, then having to fab it all up again.

[SupergasDil]

OOOOOOOOOOOOOhhhhhhhhhhhhhhhhhh!!!!!!!!!!!!!!!!!

Here's the secret weapon I'm going to use to beat Gorgeous at Norwalk.