Torque converters
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Instructor
Joined: Feb 2009
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From: Greer SC
Torque converters
Will a converter from a TH350 fit a TH400. I see in summit and jegs they list 350/375/400. If so, can you tell by looking at the converter what stall it may be. Reason I'm asking I have a 2300 stall in my TH400 now but I have a TH350 and converter just sitting around. I'm thinking about maybe going up to 2700 or 3000 stall.
Team Owner
Joined: Jul 1999
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From: Orange Park Florida
I presume you are aware that running a 'drag race special' high stall converter on the street will tend to make the tranny run hotter'n hell in the summer, you will need a LARGE extra cooler,....
much less the MPG loss....but for a digger, have fun....
much less the MPG loss....but for a digger, have fun....
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Instructor
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From: Greer SC
That was going to be my next question. Going to that high a stall what will be the effects of regular drivability? I have just replaced the rear gear set with a 3.55 and the cam I have is the comp cam 274 which is rated for 1800-6000 with a holley street dominator single plane with a jet performance stage 2 q-jet. I plan on driving to Carlisle at some point and myrtle beach and pigeon forge. I'm running a good size cooler already.
Le Mans Master
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From: League City Tx
As long as the new converter is of decent quality(ie. Not the local speed shop special) and is clean inside you should be good to go. Those 3.55s will tighten the converter up quite a bit. With that cam/intake setup, you definetly need more converter. If the converter is a good one(Ati, Coan, Yank, PTC, Precision Industries etc) it will be very efficient around town and tight on the highway....they will only get loose when you start putting your foot in it. Less throttle, less torque= less slippage.
My converter is a custom from a local guy, "tight" 10"... I can barely tell there is a stall in it at all around town. Hwy rpms only went up about 200 at 70mph....but it will flash to 3700rpms from a 1500 rpm stomp.....I only have 3.08 gears also.
If your other converter is a cheapy with unknown origin, I would wait until you can get a good one....it makes all the difference in the world. My next converter will be an ATI treemaster. And I drive my car everywhere...
My converter is a custom from a local guy, "tight" 10"... I can barely tell there is a stall in it at all around town. Hwy rpms only went up about 200 at 70mph....but it will flash to 3700rpms from a 1500 rpm stomp.....I only have 3.08 gears also.
If your other converter is a cheapy with unknown origin, I would wait until you can get a good one....it makes all the difference in the world. My next converter will be an ATI treemaster. And I drive my car everywhere...
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From: Corsicana, Tx
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Yes....to orginal question...they interchange between T-350 and T-400 assuming the T-350 is a *non-lockup* trans.
2700 isn't too much stall. But as mentioned...there are big differences between converters. You can't really tell from the outside. Many variations of 12", 11" 10" 9.5" etc converters.
Alan...I had one built years ago by Brittain transmissions off the Hardy Toll Rd. Did a GREAT job...hit my goals first try and it is still working today!
JIM
2700 isn't too much stall. But as mentioned...there are big differences between converters. You can't really tell from the outside. Many variations of 12", 11" 10" 9.5" etc converters.
Alan...I had one built years ago by Brittain transmissions off the Hardy Toll Rd. Did a GREAT job...hit my goals first try and it is still working today!
JIM
Last edited by 427Hotrod; Jun 17, 2010 at 06:48 PM.
Instructor
Joined: Jun 2010
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From: Shreveport Louisiana
There is no way of telling stall size even if you cut it open. Stay away from cheap converters, they often have adapter rings welded on to fit your flexplate. Go with a billet converter if they have them available from summit or jegs.
Thread Starter
Instructor
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From: Greer SC
Are the higher stall converters all smaller than factory. The 2300 that I have is bigger than the one I have with the TH350. Would that mean that it's "is" a higher stall. I know guy I got the transmission from and we both get ours built from the same guy so I'm not worried about the quality of the converter I'm just curious how I can find out what it is without having to put it in the car and then, if it's not what I want having to pull it out again.
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Le Mans Master
Joined: May 2006
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From: League City Tx
Are the higher stall converters all smaller than factory. The 2300 that I have is bigger than the one I have with the TH350. Would that mean that it's "is" a higher stall. I know guy I got the transmission from and we both get ours built from the same guy so I'm not worried about the quality of the converter I'm just curious how I can find out what it is without having to put it in the car and then, if it's not what I want having to pull it out again.
Usually, if the converter is built by a reputable company, smaller the case, higher the stall speed. Very generally speaking, normally a 2800-3500 range converter is in a 10" case. They are normally more efficient. But in the converter game, there are so many variables it's not even funny. Converter builders can increase stall speed several different ways when building a converter and some of these methods kill efficiency....they are loose, sloppy around town and lose trap speed in the 1/4.
Just do your homework on converters. The good thing is if you don't like it, you can pull it out. But I would spend $500'and get a custom built converter for your combo and do it right the first time.
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Instructor
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From: Greer SC
You can get different stall speeds in different size cases. It's all in how it was built. You could have a 3000 stall in a 12" converter or a 9.5"....
Usually, if the converter is built by a reputable company, smaller the case, higher the stall speed. Very generally speaking, normally a 2800-3500 range converter is in a 10" case. They are normally more efficient. But in the converter game, there are so many variables it's not even funny. Converter builders can increase stall speed several different ways when building a converter and some of these methods kill efficiency....they are loose, sloppy around town and lose trap speed in the 1/4.
Just do your homework on converters. The good thing is if you don't like it, you can pull it out. But I would spend $500'and get a custom built converter for your combo and do it right the first time.
Usually, if the converter is built by a reputable company, smaller the case, higher the stall speed. Very generally speaking, normally a 2800-3500 range converter is in a 10" case. They are normally more efficient. But in the converter game, there are so many variables it's not even funny. Converter builders can increase stall speed several different ways when building a converter and some of these methods kill efficiency....they are loose, sloppy around town and lose trap speed in the 1/4.
Just do your homework on converters. The good thing is if you don't like it, you can pull it out. But I would spend $500'and get a custom built converter for your combo and do it right the first time.
Thanks, I think that's what I'll do!
