TH400 Swap Questions

[excobraguy]

I've seen a lot of different posts on this subject and I like the thought of going to the reliability and low cost of the TH400. Some questions I have are:

1) Is there a certain year TH400 to look for or will any year work?

2) Will the current torque converter from the BRF2004r work in the TH400? (Sorry is this is a dumb question, I am tranny illiterate!)

3) What is the mod list of parts needed for the conversion, driveshaft? Crossmember? Shifter? etc....

4) Can a standard rebuild on a TH400 hold up or does it need a performance rebuild performed on it?

Sorry guys if this is duplicated information being requested, if you feel you must reply, please keep it positive...... :smile: Thanks.

Dean

Oh yeah, my setup is a 550hp+ car running mid 10's with a currently slipping BRF200r4.......

 

[gnxtc2]

I've seen a lot of different posts on this subject and I like the thought of going to the reliability and low cost of the TH400. Some questions I have are:

1) Is there a certain year TH400 to look for or will any year work?

Sort of, the early 400 have 32 element sprag compared to the later years that have the 16 element. (I think or something along those lines).

2) Will the current torque converter from the BRF2004r work in the TH400? (Sorry is this is a dumb question, I am tranny illiterate!)

No, you need to get a converter for a 400

3) What is the mod list of parts needed for the conversion, driveshaft? Crossmember? Shifter? etc....

Most get the billet yoke from Strange. unless you want to spend $$$ and get Mark William stuff. You can retain you stock crossmember and get the HR Tranny mount which has the correct offset in it. You can retain your stock shifter but need to modify the detent gate or someone was making a detent on the boards for a 400. Do a search. Can't answer you on the driveshaft as I bought a new one from Denny's.

4) Can a standard rebuild on a TH400 hold up or does it need a performance rebuild performed on it?

Depends what is meant by standard. You need to atleast get the basics, shift kit, clutches.

Sorry guys if this is duplicated information being requested, if you feel you must reply, please keep it positive...... :smile: Thanks.

Dean

Oh yeah, my setup is a 550hp+ car running mid 10's with a currently slipping BRF200r4.......

The 400 uses vacuum to shift the trans. The TR does not produce any vacuum when in boost. You need to get a manual valve body. Most go with a reverse valve with a trans brake.

Also look for a BOP 400. This is a 400 with the bellhousing for a Buick. If you go with an UltraBell which is SFI approved, it has a dual bolt pattern.

Need a dipstick also. You can get a Lokar flex one but they aren't the locking type as required by NHRA. Lokar is supposed to be coming out with a new line of locking flexible dipsticks. I think I bought my locking dipstick and tube from TCI.

Billy T.
gnxtc2@aol.com

 

[jwillettgn]

1. Get a T-400 from one of the vendos here as some mods need to be done to keep it from taking out the engine's thrust bearing.

2. You will need a new converter.

3. We are using the stock shifter but will have to make a cable mount at the trans end. Simple mod.

4. We got a T-400 transmission mount from HR Parts that bolts in.

5. You will need a new driveshaft.

We got ours from CK Performance with a JW ultra bell and a Trans brake.

Jim

 

[excobraguy]

Sort of, the early 400 have 32 element sprag compared to the later years that have the 16 element. (I think or something along those lines).



No, you need to get a converter for a 400



Most get the billet yoke from Strange. unless you want to spend $$$ and get Mark William stuff. You can retain you stock crossmember and get the HR Tranny mount which has the correct offset in it. You can retain your stock shifter but need to modify the detent gate or someone was making a detent on the boards for a 400. Do a search. Can't answer you on the driveshaft as I bought a new one from Denny's.



Depends what is meant by standard. You need to atleast get the basics, shift kit, clutches.



The 400 uses vacuum to shift the trans. The TR does not produce any vacuum when in boost. You need to get a manual valve body. Most go with a reverse valve with a trans brake.

Also look for a BOP 400. This is a 400 with the bellhousing for a Buick. If you go with an UltraBell which is SFI approved, it has a dual bolt pattern.

Need a dipstick also. You can get a Lokar flex one but they aren't the locking type as required by NHRA. Lokar is supposed to be coming out with a new line of locking flexible dipsticks. I think I bought my locking dipstick and tube from TCI.

Billy T.
gnxtc2@aol.com

What is meant by BOP? Thanks for all of the info, also....I can get a TH400 tranny at any of my local salvage yards for $350 or less, how much more on top of that would you say will be required?

 

[excobraguy]

1. Get a T-400 from one of the vendos here as some mods need to be done to keep it from taking out the engine's thrust bearing.

2. You will need a new converter.

3. We are using the stock shifter but will have to make a cable mount at the trans end. Simple mod.

4. We got a T-400 transmission mount from HR Parts that bolts in.

5. You will need a new driveshaft.

We got ours from CK Performance with a JW ultra bell and a Trans brake.

Jim

Curious, what was your cost for this setup and how reliable has it been?

 

[SIXBANGR]

your torque convertor can be changed to work, just talked to Art Carr a few minutes ago. He will do one of his anyway.

Do you have a picture of the cable mount you made. It would be nice to use the stock stuff. Any thing else have to be done to the shifter?

 

[mikestertwo]

What is meant by BOP? ?

Buick, Olds, Pontiac

 

[excobraguy]

Buick, Olds, Pontiac

Now I feel smart, duh!!!!!!!!!:smile:

 

[excobraguy]

Anyone else have any input, what can I buy a TH400 for from one of the vendors off of here for? Any vendors?????

 

[excobraguy]

Damn, Am I the only one playing on the internet at work today????

 

[KevinB]

Anyone else have any input, what can I buy a TH400 for from one of the vendors off of here for? Any vendors?????

Lonnie Diers at Extremeautomics is a vendor here and builds some very nice th400's. I have one in my car. Basically mines stock with good clutches and a tci manual valve body....nothing fancy, but it works.

 

[SIXBANGR]

Len Freeman in Vegas is a damn good trannie man.

 

[jwillettgn]

Link to CK Performnce:

www.CKPerformance.com

Jim

 

[excobraguy]

Link to CK Performnce:

www.CKPerformance.com

Jim

Thanks for the link!

 

[jakeshoe]

Where are you located at. That helps when recommending a trans shop. Good shops all over the country but usually no reason to buy a trans on one coast if you live on the other

 

[$1987 GN$]

The 400 uses vacuum to shift the trans. The TR does not produce any vacuum when in boost. You need to get a manual valve body. Most go with a reverse valve with a trans brake.
Billy T.
gnxtc2@aol.com

There is a cable operated modulator, no vacuum needed. It uses a 700R4 throttle valve cable. ~90 bux

Just thought you might like to know.

Later AJ

 

[norbs]

Check the cooler line psi and make sure its 40 max cold or you will be pulling the thrust bearing in the motor weekly. Read the thread "thrust bearing"

 

[YouLikeThat]

Lonnie Diers at Extremeautomics is a vendor here and builds some very nice th400's. I have one in my car. Basically mines stock with good clutches and a tci manual valve body....nothing fancy, but it works.

+1 on the stock with good clutches and a hipster valve body. I'm also very happy with my Neil Chance converter. See Sig.

 

[1BADTT]

Subscribing...

Great info.

 

[excobraguy]

Great info.

I agree, absorbing it all in. I love this board!!!!!! And thanks to all of you guys for contributing.........Anyone else have any info on your TH400 conversion????? By the way, I am just south of St. Louis Missouri, if there are any good TH400 builders near here :biggrin: