Stock class transmission case breakage
 

Recently, I have received a large amount of concern over automatic transmission case breakage and safety concerns. I am interested in finding out how much a problem this is in the stock class. Your comments are greatly appreciated.

Tracy Winters

Re: Stock class transmission case breakage
 

Not a problem for us. However, we already approached NHRA, they are unwilling to accept aftermarket cases in Stock Eliminator. Well, at least for the automatic transmission cars.

Re: Stock class transmission case breakage
 

The only time I have encountered trans case breakage was due to chassis flex. With a properly installed roll cage and proper bracing there should not be any case breakage. Solid motor mounts, rubber trans mount and no chassis flex should eliminated breadage.

Re: Stock class transmission case breakage
 

I recently had this problem with the TH350 in my stocker. We never could figure out why the case broke like it did, but I called Wesley (Div. 4 tech man) and was told that OEM case only. It seems as though NHRA would rather leave it alone or move Stock into Superstock rather than allowing more superceded parts like trans cases.

Re: Stock class transmission case breakage
 

I've broken just one case in 30 years of racing and that was related to a U-joint failure....knock on wood!

Re: Stock class transmission case breakage
 

I agree. I think using the wrong type of mount would cause our cars the most trouble. On a related note, do the JW bellhousings with the 30.1 flex plate sheild rating require indexing?

Re: Stock class transmission case breakage
 

So NOW the NHRA does not want to allow better parts. It like closing the barn door after the cows have all left the farm !

Re: Stock class transmission case breakage
 

The bellhousing is SFI certified 30.1 for the flexplate shield and it fits onto the stock transmission case. You do not have to use an aftermarket transmission case. If I am correct the flexplate shield is required for vehicles running 10.90 or faster. I am not sure that I understand the question regarding the indexing? Let me know how I can assist you further.

Re: Stock class transmission case breakage
 

Tracy- PM Sent

Re: Stock class transmission case breakage
 

We index them. Have seen them off as far as .035". I'd rather be safe than sorry. $0.02
Larry