turbo 400 question

Seate Boys · 10-17-2011, 09:54 PM

Keep busting the case on my camaro,in the bell housing area.Want to go to the "JW Ultrabell",one is an "LS" part number and one is not.I assume it means long shaft,what's the diff.All the casings I've had look the same

Tom Goldman · 10-17-2011, 10:13 PM

The LS suffix means it will fit all GM engines including LS series .
you want the 92451 for the TH400

Seate Boys · 10-18-2011, 09:43 AM

Thanks Tom,the guy at Summit said he showed 2 #'s,one understood by him 2 b long shaft

Alan Roehrich · 10-18-2011, 10:03 AM

A TH400 case is very tough, if you're breaking them, the problem is not likely to be the case. The most common problems are drive shaft, motor mount, and chassis problems. The case on a TH400 will take well over 1000HP with ease, provided you do not have another problem.

Tom Goldman · 10-18-2011, 12:28 PM

Alan, I agree the 400 is one tough case ,but lately the supply of used cores from the salvage yards seems to be getting pretty beat up.
I've had several salvage yard cores recently with cracks showing up in the bell area after they were cleaned.

The other issue I've seen is from cars that are big wheelstanders with no mid plate. i.e. Stock and some brackets cars. Not that many racers run them in Stock anymore.
They seem to have more issues with cracks than others.

Alan Roehrich · 10-18-2011, 01:31 PM

Tom, my only point was if that if a racer is cracking cases that did not start off cracked, changing the bellhousing is not necessarily going to solve the problem, and it may only make the case break somewhere else.

When I was the manager of the racing side of a very successful transmission shop, I found that it was extremely rare for a case to break of its own accord. The vast majority of problems, as you said, were due to either chassis flex, or motor mount problems, although we did find a few driveshaft problems.

A big concern is that if the bellhousing is breaking, and you replace it with a stronger bellhousing, and don't resolve the cause of the breakage, the next place it breaks is behind the pump, and that creates a fluid loss hazard that can cause a crash and/or a fire.

Tom keedle · 10-18-2011, 07:28 PM

solid trans mount maybe?

Jimmy70RSSS · 10-19-2011, 12:29 AM

Had a friend with a similar problem with a T400. After changing the bellhousing it would strip the pump bolts and dump fluid! Chassis flex was the problem. Converted to a 10 point and tied the frame where the backhalf met the stock front and it hasn't hurt anything in 3 years.

10-17-2011, 09:54 PM	#1
Seate Boys Junior Member Join Date: Oct 2011 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	turbo 400 question Keep busting the case on my camaro,in the bell housing area.Want to go to the "JW Ultrabell",one is an "LS" part number and one is not.I assume it means long shaft,what's the diff.All the casings I've had look the same

10-17-2011, 10:13 PM	#2
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,438 Likes: 786 Liked 703 Times in 206 Posts	Re: turbo 400 question The LS suffix means it will fit all GM engines including LS series . you want the 92451 for the TH400 __________________ Tom Goldman 1500 SG , 1506 STK

10-18-2011, 09:43 AM	#3
Seate Boys Junior Member Join Date: Oct 2011 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	Re: turbo 400 question Thanks Tom,the guy at Summit said he showed 2 #'s,one understood by him 2 b long shaft

10-18-2011, 10:03 AM	#4
Alan Roehrich VIP Member Join Date: May 2006 Location: Murfreesboro TN Posts: 4,934 Likes: 1,019 Liked 1,093 Times in 286 Posts	Re: turbo 400 question A TH400 case is very tough, if you're breaking them, the problem is not likely to be the case. The most common problems are drive shaft, motor mount, and chassis problems. The case on a TH400 will take well over 1000HP with ease, provided you do not have another problem. __________________ Alan Roehrich 212A G/S

10-18-2011, 12:28 PM	#5
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,438 Likes: 786 Liked 703 Times in 206 Posts	Re: turbo 400 question Alan, I agree the 400 is one tough case ,but lately the supply of used cores from the salvage yards seems to be getting pretty beat up. I've had several salvage yard cores recently with cracks showing up in the bell area after they were cleaned. The other issue I've seen is from cars that are big wheelstanders with no mid plate. i.e. Stock and some brackets cars. Not that many racers run them in Stock anymore. They seem to have more issues with cracks than others. __________________ Tom Goldman 1500 SG , 1506 STK

10-18-2011, 01:31 PM	#6
Alan Roehrich VIP Member Join Date: May 2006 Location: Murfreesboro TN Posts: 4,934 Likes: 1,019 Liked 1,093 Times in 286 Posts	Re: turbo 400 question Tom, my only point was if that if a racer is cracking cases that did not start off cracked, changing the bellhousing is not necessarily going to solve the problem, and it may only make the case break somewhere else. When I was the manager of the racing side of a very successful transmission shop, I found that it was extremely rare for a case to break of its own accord. The vast majority of problems, as you said, were due to either chassis flex, or motor mount problems, although we did find a few driveshaft problems. A big concern is that if the bellhousing is breaking, and you replace it with a stronger bellhousing, and don't resolve the cause of the breakage, the next place it breaks is behind the pump, and that creates a fluid loss hazard that can cause a crash and/or a fire. __________________ Alan Roehrich 212A G/S

10-18-2011, 07:28 PM	#7
Tom keedle Senior Member Join Date: Dec 2008 Location: Berthoud, Coloraduh Posts: 695 Likes: 13 Liked 7 Times in 6 Posts	Re: turbo 400 question solid trans mount maybe?

10-19-2011, 12:29 AM	#8
Jimmy70RSSS Junior Member Join Date: Apr 2011 Posts: 5 Likes: 1 Liked 0 Times in 0 Posts	Re: turbo 400 question Had a friend with a similar problem with a T400. After changing the bellhousing it would strip the pump bolts and dump fluid! Chassis flex was the problem. Converted to a 10 point and tied the frame where the backhalf met the stock front and it hasn't hurt anything in 3 years.