TH400, what will this hold?
02-29-2012, 06:14 PM
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TH400, what will this hold? For the TH400 experts, any idea how much power the trans will hold? Can pick it up for a decent price. Thanks!
400 T transmission
Manual Rev. valve body
Raybestos “RED” clutches/ band
Deep pan
Roller output bearing
Dual feed direct drum
FRESH BUILD
400 T transmission
Manual Rev. valve body
Raybestos “RED” clutches/ band
Deep pan
Roller output bearing
Dual feed direct drum
FRESH BUILD
02-29-2012, 07:49 PM
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Thanks for the info. Just got off the phone with the guy, he said it has a 16 element which came with the RV's and big trucks, or something like that. I guess he has a pretty good rep and builds some of the cars at our local track. I asked him what it would hold and he said there are a couple of big blocks at our track pushing around 800hp with this same trans. Sound like BS or is that possible?
Trans is $600. He said he could build a th350 that can hold 650hp for around $550-600.
Trans is $600. He said he could build a th350 that can hold 650hp for around $550-600.
02-29-2012, 10:25 PM
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Thanks for the info. Just got off the phone with the guy, he said it has a 16 element which came with the RV's and big trucks, or something like that. I guess he has a pretty good rep and builds some of the cars at our local track. I asked him what it would hold and he said there are a couple of big blocks at our track pushing around 800hp with this same trans. Sound like BS or is that possible?
Trans is $600. He said he could build a th350 that can hold 650hp for around $550-600.
Trans is $600. He said he could build a th350 that can hold 650hp for around $550-600.
02-29-2012, 10:32 PM
#5
Put it this way... that trans has more than $600 in parts.
You can take a stock valve body and modify it to a fully manual valve body but if it's a reverse pattern it's a $200 valve body.
Your clutches, bearings and pan are easily $200.
Even if it is only a 16 element sprag (which is frowned upon by many), I see it as a great thing! That means you have the early style direct drum... for $60-90 you can get a 34 element sprag and it is simple to change.
However, I don't believe him one bit. If he rebuilt it and is selling it for a profit (as a business), he didn't do anything to it. I am a fan of "you get what you pay for".
And if everything he said is true, switch to a 34 element sprag and you can throw 800 crank horse at it without blinking.
You can take a stock valve body and modify it to a fully manual valve body but if it's a reverse pattern it's a $200 valve body.
Your clutches, bearings and pan are easily $200.
Even if it is only a 16 element sprag (which is frowned upon by many), I see it as a great thing! That means you have the early style direct drum... for $60-90 you can get a 34 element sprag and it is simple to change.
However, I don't believe him one bit. If he rebuilt it and is selling it for a profit (as a business), he didn't do anything to it. I am a fan of "you get what you pay for".
And if everything he said is true, switch to a 34 element sprag and you can throw 800 crank horse at it without blinking.
03-01-2012, 04:24 PM
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He told me 16 element sprag, he had to go find his parts sheet and didn't lie about it having a 34 element when I asked, so idk why he would lie about it having the 16. Never know though. He said 16 element and something about a wishbone, I have zero knowledge when it comes to transmissions. I think the price is fairly cheap because he told me he builds a couple of spares just in time for tax season, so these are just sitting there.
I know he has a pretty good rep in the area and people from local forums either know him or know of him, so if I were to get screwed it wouldn't take much to ruin that rep in such a small location.
So the trans + 34 element and I'm good to go? Appreciate the input everyone.
I know he has a pretty good rep in the area and people from local forums either know him or know of him, so if I were to get screwed it wouldn't take much to ruin that rep in such a small location.
So the trans + 34 element and I'm good to go? Appreciate the input everyone.
03-01-2012, 09:39 PM
#9
If you have no experience with it, I wouldn't change it.
The biggest issue here is GM made 16 element sprags for 3-4 years and then the rest of the TH400's life was spent with a 16 element roller. The roller design isn't bad by any means and it's difficult to explain why they fail. Elements are the equivalent to ball bearings. Basically, a roller assembly has teeth that don't allow it to slip and force it to strip/bend/blow out the elements while a sprag assembly is rounded and if push comes to shove it will just keep doing its job.
The sprag assemblies are desired by anybody with half a brain but in order to switch from roller back to sprag it is pricey (around $400 aftermarket) and even used it will cost close to $200... if you can even find a used sprag style direct drum. Why he didn't change the sprag (if it really is a sprag) to a 32 element for $60-90 is beyond me.
I just can't see how this transmission is full of half-decent parts if the parts list adds up more than the asking price... now add a good TH400 core and that's another $200-300.
A more logical solution is he's old school. I believe a dual feed direct drum is when you just add extra clutch packs. Not very good with my terminology though. I know a stock valve body can be modified to be manual pretty easily so once again he isn't spending any money on it.
The biggest issue here is GM made 16 element sprags for 3-4 years and then the rest of the TH400's life was spent with a 16 element roller. The roller design isn't bad by any means and it's difficult to explain why they fail. Elements are the equivalent to ball bearings. Basically, a roller assembly has teeth that don't allow it to slip and force it to strip/bend/blow out the elements while a sprag assembly is rounded and if push comes to shove it will just keep doing its job.
The sprag assemblies are desired by anybody with half a brain but in order to switch from roller back to sprag it is pricey (around $400 aftermarket) and even used it will cost close to $200... if you can even find a used sprag style direct drum. Why he didn't change the sprag (if it really is a sprag) to a 32 element for $60-90 is beyond me.
I just can't see how this transmission is full of half-decent parts if the parts list adds up more than the asking price... now add a good TH400 core and that's another $200-300.
A more logical solution is he's old school. I believe a dual feed direct drum is when you just add extra clutch packs. Not very good with my terminology though. I know a stock valve body can be modified to be manual pretty easily so once again he isn't spending any money on it.
