cracked tranny

[halfcracked]

I just got the fireturd up on the hoist & low & behold another cracked 350 trans >: (,guess the car is living up to its name) . This spring I replaced the solid mounts with rubber ones (trans & engine),to try & stop this from happening . The trans was a fresh unit first race at Greenfeild,any suggestions out there on how to remedy this. One was to drill holes in bellhousing as stress relief holes . The car has subframe connectors welded in.

[stk1201]

My question is do you have a "engine hold down strap" on the left side of your car or just your rubber motor mount?

[halfcracked]

I do not have a strap on left side , but use to have solid mounts with same results. Some have suggested maybe too much pinion angle?

[56chevtruck]

tommy thats odd?we did darrel pooles nova solid mounts motor and tranny and no breakage. did you ever use solid and rubber together you will break stuff that way.

[Mitch Bonnar]

After learning that you have had solid mounts as well as rubber mounts and still continue to break bell housings it is my 2 cents worth that the pinion angle may be the culprit. You may also want to look at the driveshaft lenght to assure that it is not too long and binding at rear of the transmission while launching. ( as the car squats the driveshaft likley goes into the transmission further ).
As a last resort try leaving in high gear, there will be a lot less twisting of the frame and the cars front wheels will stay on the ground..............jusrt kidding. ;D

[Stuart]

Is you engine/tranny offset in the chassis compared to the rearend? if it is it could be putting some type of a "side load" on your bellhousing. Did both the tranny's break in the same place?

[Mitch Bonnar]

I went over to his shop tonight and yes the rear end is offset about 2 inches and all 4 broken trannies were broken in the same place.

Because there are lots of cars with that offset that setup should not be a problem but since he has broken 4, he has tried solid mounts, rubber mount on the trans only, rubber mounts all round, it may be prudent to try this:

I suggested a aftermarket Bell Housing and here is the poop on what I found from J.W.

JW-92452 TH350 Ultra Bell $199.60

www.tsr-racing.com/catalog/pg_prices.html

That may be the easiest way to skin that cat.

[halfcracked]

Hi there stuart the rear end is offset an inch or so to the right of center line ,this was done to allow room for the tourqe arm in the original set up from factory. Mitch was over tonight & had a look ,took some measures, studied the setup went home to sleep on it. I was taking the car to Sydney,but now it looks like I,ll have to rent a racer,helmet & shoe polish in the trailer. The last couple of trans have cracked in the same place, I will try to post some pictures later,off to Sydney tomorrow!!

[halfcracked]

Hi Mitch guess your faster typing than me, i,m still in the one finger mode call you in the morning

[Stuart]

I just thought it might be something to look at. If you broke all 4 in the same place then that is the spot that is taking all the stress. Is the back of your engine true?
Maybe there is a high spot on the mating surface?

[lowrider]

I WAS THINKING THAT IT COULD BE A HIGH SPOT ASWELL , WHEN YOU PUT TRANS BACK IN THE TWO LINE UP PINS WAS STILL IN PLACE ?

[protopline]

Did u find the problem yet? I pulled my tranny out 2 yrs ago to freshen it up and everything inside looked good so i started putting it back together and before i had it finished i was cleaning up the case to give it a splash of paint and noticed the bell housing cracked. I then used another case and sent my driveshaft to be rebalanced and straighten in Moncton. Never had a problem since (Knock on wood)lol. I also had a friend who had a 83 style camero S/Pro that went through 6 case in 6 weekend and braced everything on his engine & tranny which did not help. He then checked his shaft and it was out of balance and bent. He then bought a new one and raced the rest of the year approx 4 weekends with the small cracked tranny still in the car which never cracked any farther. Maybe something else to look at.
Chad