TH400 build-pictures

[jakeshoe]

In my experience the TransGo kit runs into issues at ~500 HP in a car that is raced frequently.

The method they use to dual feed doesn't have enough fluid volume to fill the drum quick enough.

It is still the best kit on the market for a bolt in kit, but the dual feed must be internally done above 450-500 HP to make the directs live.

 

[87buickracer]

Trans-go just released a 400-pro kit you may want to check into.
General Motors Reprogramming Kits
I would buy at,
3L80 & 400 Valve body kits: Bulkpart transmission parts

great price on the kit.I tried to get the video to play,having problems with my computer.

 

[87buickracer]

Another cool little item . Will require a hardened yoke.

sweet,what's the price on this piece?

 

[turbobitt]

It's $215 big ones. A little pricy but it is nice.
TCI Auto: PRO-X™ TH400 Aluminum Tailhousing With Roller Bearing

 

[87buickracer]

It's $215 big ones. A little pricy but it is nice.
TCI Auto: PRO-X™ TH400 Aluminum Tailhousing With Roller Bearing

yeah,but worth the money in the long run..
nice piece to have for extra insurance.

 

[Alky V6]

The needle bearing in the extention housing deal is not an absolute necessity. The reason people have put needle bearings in there is because in a high speed/endurance application the bushing will overheat and wear. The cure is to simply run pressurized oil to the bushing. Nothing new. Problem solved.

 

[turbobitt]

Don,
I have had several housings that the bushing to yoke fit was much looser then I would like to see. This housing seems to have a beter fit to the yoke.

 

[chris718]

The normal oil feed to the bushing in the extension housing is bleed off oil from the governor shaft that accumulates or sprays into the extension housing and winds up on the bushing.There was an early and late style governor and output shaft combination that worked this out.Some oil is channeled back there from the case bushing as well.When we dont have a governor it reduces(but not eliminate) the oil fed to the extension housing bushing .This is usually not a problem in a drag car but when street driving it can cause premature bushing failure.Failures of this type are very few however I am a believer in overkill on anything pushed beyond its original design limitations.:biggrin:

 

[bison]

The needle bearing in the extention housing deal is not an absolute necessity. The reason people have put needle bearings in there is because in a high speed/endurance application the bushing will overheat and wear. The cure is to simply run pressurized oil to the bushing. Nothing new. Problem solved.

I disagree. The factory clearance tolerances sucked horribly on this part like other areas of the trans like you stated in an earlier post about bushing clearance problems. For a car like Bitt's that will see 155+mph trap speeds in the future this is a very worthwhile mod. Excellent output shaft and yoke stability can be achieved everytime. With a driveshaft speed over 6500rpm id want all the stability i can get. The cost isnt $hit when looking at the big picture.

 

[Otto J]

I disagree. The factory clearance tolerances sucked horribly on this part like other areas of the trans like you stated in an earlier post about bushing clearance problems. For a car like Bitt's that will see 155+mph trap speeds in the future this is a very worthwhile mod. Excellent output shaft and yoke stability can be achieved everytime. With a driveshaft speed over 6500rpm id want all the stability i can get. The cost isnt $hit when looking at the big picture.

Great point Brian.the stabilty will be worth it in removing another possible driveline vibration that the worn or loose bushing can cause.

 

[Alky V6]

The only thing that would hold me back from going with the needle bearing housing would be the yoke. I have never seen a yoke with a needle bearing quality sleeve. If there is one, what does it cost?

 

[Otto J]

The only thing that would hold me back from going with the needle bearing housing would be the yoke. I have never seen a yoke with a needle bearing quality sleeve. If there is one, what does it cost?

Can you send out a new one and have it hardend and or nitrided?
Maybe a new billet one

 

[chris718]

Yokes arent sleeved.The od of the "sleeve" is rough finished to a rough spec.The i d is then broached and then the part is heat treated and ground.After this the span joint is attached to the sleeve.The bearing and sleeve must be at a compatable heat treat or metal transfer will take place.Most of the major axle and diff suppliers have tuffer yoke sleeves as the roller bearing has been used on lencodrive and manual transmissions as well so the surface finish and hardeness has already been researched and the parts aree available and have been for quite some time.

 

[Otto J]

They have been doing this mod to glides forever.

 

[Alky V6]

So how much do one of those special yokes cost? I've seen a Mark Williams billet for the 200-4R and I know it isn't roller bearing quality. Can anyone direct me to a site? I'm curious.

 

[87buickracer]

In my experience the TransGo kit runs into issues at ~500 HP in a car that is raced frequently.

The method they use to dual feed doesn't have enough fluid volume to fill the drum quick enough.

It is still the best kit on the market for a bolt in kit, but the dual feed must be internally done above 450-500 HP to make the directs live.

Hey Jake,I completed the dual feed mod I read in your article you did.But you didn't cover any mods done to the pump with pictures.Overall that was a great article on th400 tips and tricks,so I saved it.

 

[jakeshoe]

Yeah,
I've been in Iraq since late 2007 so I'm behind on everything.

I'll add to those articles time permitting in the future.

Nothing fancy to the pump. restrict the converter feed and good clearances on the TH400 is about all that is needed.

 

[Gregaust]

Jake or anyone else , can i ask what you would do with a direct drum when you end up with no checkball in the piston? Option would be to source an early piston??? Is there an aftermarket one available?
I'm nervous on drilling the drum too much. It currently has a small .040" bleed hole for high rpm. Thanks

 

[Alky V6]

I would stick with what you have there, including the piston. I wouldn't go any bigger with that hole. I know that 1/16 has been the norm for decades. I just feel it's too big. Back in the day of TFs, it used to be recommended to drill a .030" in the reverse servo piston to relieve any oil that happened to crossleak into the reverse servo circuit. I can't imagine the 400 has that bad of a crossleaking issue to need a 1/16" hole.

 

[jakeshoe]

I agree with Don.
A .040" bleed hole is sufficient and no checkball is needed now, as the drum will exhaust.