PY Online Forums - Bringing the Pontiac Hobby Together

PY Online Forums - Bringing the Pontiac Hobby Together (https://forums.maxperformanceinc.com/forums/index.php)
-   Pontiac - Race (https://forums.maxperformanceinc.com/forums/forumdisplay.php?f=419)
-   -   Broken Rear (https://forums.maxperformanceinc.com/forums/showthread.php?t=415078)

Craig Berkheimer 10-22-2000 10:12 PM

Well the 12 bolt took a dump off the line hanging a right. Quite a ride! http://performanceyears.com/ubb/eek.gif I discovered the housing were the tubes are slid into split the case. Yes, they were tig welded but I didnt have any support to the outer ends. I understand once you get to this point, you need to start looking at a stronger rear.

Does anyone use a 12 bolt, 60fting in the 1.30s with any long term success? If so, what modifacations have you made.

How about 4130 tubes with both ends welded to the housing and triangular support bars?

------------------
Outlaw Pontiac Racers Association
"For Those Who Live The Legend" www.outlawpontiacs.com


JBP 416ci on Gasoline
#16 Dports 10.8-1 Compression
Weight - 3275
10.5 - 29.5 TIRE
Best ET: 60ft=1.39
1/8 =6.49@104mph
1/4 =10.29 @ 129mph

[This message has been edited by Craig Berkheimer (edited 10-22-2000).]

Craig Berkheimer 10-22-2000 10:12 PM

Well the 12 bolt took a dump off the line hanging a right. Quite a ride! http://performanceyears.com/ubb/eek.gif I discovered the housing were the tubes are slid into split the case. Yes, they were tig welded but I didnt have any support to the outer ends. I understand once you get to this point, you need to start looking at a stronger rear.

Does anyone use a 12 bolt, 60fting in the 1.30s with any long term success? If so, what modifacations have you made.

How about 4130 tubes with both ends welded to the housing and triangular support bars?

------------------
Outlaw Pontiac Racers Association
"For Those Who Live The Legend" www.outlawpontiacs.com


JBP 416ci on Gasoline
#16 Dports 10.8-1 Compression
Weight - 3275
10.5 - 29.5 TIRE
Best ET: 60ft=1.39
1/8 =6.49@104mph
1/4 =10.29 @ 129mph

[This message has been edited by Craig Berkheimer (edited 10-22-2000).]

Bracket Racer 10-22-2000 11:30 PM

Craig - That's a real bummer to hear. Frankly, I think your pushing the envelope now as far a what a 12 bolt will take. I'd start looking for a Dana or a 9 inch. So it broke the gear housing where the tubes are welded? Or did the tube(s) just break the weld(s)? Guess this put's the trans-brake project back a little further?

Craig Berkheimer 10-23-2000 07:00 AM

I was on the last pass, 2nd round, to take the 2000 Outlaw Pontiac Drag Series Championship as well! I only needed that round to clinch it. I had a .552 bulb to my apponates .646 He was also a 14 second car. It would have been a kill for sure The Badbird was running dead nuts. The second place dude, Ted McGann, had to win that event to push me out. Wounldn't you know it, he went four more rounds and won the event and pushed me to 2nd place by 9 points. I guess I should have waited to run those 10.20s at Cecil another week.

To answer your question,It broke the housing! Right where GM welds the tube to the housing in that hole. Split it pretty good!
You don't think the 4130 tubes and angle bracing will do the job?

PONTIAC DUDE 10-23-2000 07:47 AM

9", more options and reliability.

WDCreech 10-23-2000 08:35 AM

Craig,
I ran a narrowed 9" in my "64 at 10.20s and bent both tubes. I now have a "Fab 9". If you decide to go with a 9" be sure to put a back brace on it. Incidentaly the fabricated housing cost me just under $1000 bare. You might check with some of the chassis builders. most of them sell rears.

------------------

Bill

Joe Corso 10-23-2000 08:45 AM

DANA. The only real choice. why spend 1100 on aFord 9 when you can get a DANA for 1700.

WDCreech 10-23-2000 09:02 AM

Those Dana's are tuff. That might be the way to go. I would've used one but I change gears to run at an 1/8 mile track. Craig, if you don't change gears often the Dana is almost indistructable.

------------------

Bill

Scott Misus 10-23-2000 11:01 AM

Craig:

Jim Swarr, here in Collegeville, does the rear end work for S&W. Two years ago, he quoted me just under $1300 to do a Dana for a street 'Bird. That included everything including NEW Moser 35 spline axles, NEW Dana posi and NEW Dana 3.54 gears. A spool would certainly cost you less. Email me if you need his phone number and more information.

A friend of mine who is a ProMod racer and does chassis work in the winter months yanks the heavy tubes out of the Dana and replaces them with lighter moly tubes. His business is in Danbury, CT and goes by the name of Speedworks. He's also very inexpensive.
Again, email me if you need a phone number and details.

In my opinion, the Ford 9" is like a small block Chevy: by the time it's built for real performance and durability, there are no longer any stock pieces in it anymore. Sort of like an IA block, Wenzler heads, Bryant crank, etc...."Yeah, but it's still a Pontiac.."

The Dana is a "drop it in and forget it" rear.


------------------
Never been banned here...
Because I've got MANNERS
....I've been warned a coupla times, though...

[This message has been edited by Scott Misus (edited 10-23-2000).]

Gach 10-23-2000 01:52 PM

I run a 12 bolt, with the axles support system, and a TA cover, and steel caps, spool, and Pro gear. What moves is the caps, then cracks the housing. The TA cover keeps pressure on the caps, keeps them from moving. The axle support system keeps the tubs from bending.

If I had it to do over again, I'd go Dana or 9", even with the axle supports, you have to keep an eye on the tubs, because they still bend, I've had to straighten them once already, high maintenance

John Langer 10-23-2000 07:00 PM

Don't laugh, this really works! 8.5 10-bolt, moser 35 spine axels (w/ c-clip eliminators), light weight spool, precision gears, TA cover, 1 billet cap or studded stock caps, weld your axel tubes at the housing, weld a bar from where your ladder bar bracket welds to the tube to the closest point to the front of the housing ( by the pinion shaft)on both sides. lighter and stronger then a 12 bolt, dana or 9". You have to check the alignment of the axel tubes prior to doing any modifications to make sure that they are straight. With the extra money you have left over after selling you 12 bolt, get drunk!

Scott Misus 10-23-2000 08:28 PM

John:

My mind is drawing a blank.

From the tube where the ladder bar (or 4 link) mounts to the forward part of the housing? I'm lost. Please explain how to weld to the iron center section. Or is this a girdle deal, like the tube braces that Gach mentioned?

Craig Berkheimer 10-23-2000 09:23 PM

ditto what Scott said.

John Langer 10-24-2000 05:44 AM

The supports that you guys are talking about are mounted on the cover side of the rear. I have my bars (around 1" od) welded on the other side and they make what is a visual triangle when welded to the center section with respect to the axel tube. This rear is just as strong as those heavy 9" and dana's but is a fraction of the cost. People will give you an old 10-bolt but want a fortune for a 9".

Scott Misus 10-24-2000 07:18 AM

So, you weld these bars to a bracket and then weld the bracket to the cast iron center section? Sounds like you'd have a heat sink problem welding a metal tab to an iron housing.

I'd be interested in seeing it. Are you going to have this car at Atco on Nov. 11th?

Scott Rex 10-24-2000 08:05 AM

Craig, I would go with a 9". I have boxes of broken parts from my 12 bolt. Your car is leaving hard, too hard for a 12 bolt.

Triggerman 10-24-2000 08:39 AM

Scott, proper pre-heating will allow this to be done. It's a similar condition to welding the axle tubes to the center section, which is common practice. TM

mike nixon 10-24-2000 08:56 AM

moser engineering should be able to set you up with a nine inch for your application. they have started shipping assembled rear ends recently. they will custom build an assembled unit for you if that's what you want. just have all of you dimensions handy when you call. if you want a bare housing they should be able to set you with that also.
they also carry wildwood brakes if you don't have rear disc already.their phone number is 1-219-726-6689. mike

Gach 10-24-2000 03:34 PM

Kenny French, run's 9.50's with the same set up, I run, has never pop a rear yet. As long as you keep your eyes on the axle tubes, you'll be all set. But hey, if you don't want the hassles then go Dana, or Ford 9". Oh one more guy who was on the cover of Hot Rod, fastest street car shot out, runs 8.20's, 67 Nova, guess what he runs for a rear 12 bolt, same set up. So it's pretty strong set up.

Craig Berkheimer 10-24-2000 05:58 PM

I just got off the phone with Moser. They are now making their own complete 12 bolt with "Fabracated" housing, 4130 tubes welded on the outside and the inside! Any length with any ends. New steel caps. $590.00
I think I'm going this way.

I fiqure with the LPW cover and triangular support, this should do the job.

------------------
Outlaw Pontiac Racers Association
"For Those Who Live The Legend"
www.outlawpontiacs.com


JBP 416ci on Gasoline
#16 Dports 10.8-1 Compression
Weight - 3275
10.5 - 29.5 TIRE
Best ET: 60ft=1.39
1/8 =6.49@104mph
1/4 =10.29 @ 129mph


All times are GMT -4. The time now is 08:41 PM.