TH400 build-pictures

[87buickracer]

th400 build

picture of transgo bypass valve for supercharged and turbocharged engines..

also I would like to know how much to take off driveshaft when installing 400 tranny.when we did jesse's car I think it was 1/2".I will be taking it over to driveline to get it cut, balanced and install yoke.

any pictures of pump converter feed restriction with details and transmission mount on cross member.I think I read somewhere that hnr parts has the poly mounts for the 400.

 

[Gregaust]

Thank you Don and Jake. Much apprecaited.

That Transgo valve is very interesting. So that will allow auto shifts with boost then? Any chance of seeing the diagram in the instructions. Have experimented here with 2 non-return valves but didn't work . Have ended up in the past using manual valvebodies and doing away with modulator.

 

[87buickracer]

Thank you Don and Jake. Much apprecaited.

That Transgo valve is very interesting. So that will allow auto shifts with boost then? Any chance of seeing the diagram in the instructions. Have experimented here with 2 non-return valves but didn't work . Have ended up in the past using manual valvebodies and doing away with modulator.

sure,I will post picture of valve tomorrow.price for this valve was 29.99

 

[Gregaust]

Thanks . Just not seen that setup before.

 

[87buickracer]

th400 build

completed the 2-3 accumulator feed mod,thanks to jakeshoe.
found the converter feed mod posted by DonWG.

 

[87buickracer]

th400 build

th400 converter feed restriction,from donwg
I did some digging to find this one.
Hey don,where did you find the set screw with hole or did you make it?
and also,what size is it?
Thanks,this will be my last mod to the tranny.

 

[Alky V6]

It's a 1/8 npt allen plug. The hole is 7/64". Drill the existing hole with a 29/64" drill bit, deep enough to tap for the pipe plug. Make sure you knock down any high spots off the mating surface with a fine mill file after you do the mod.

 

[chris718]

If you use a 5/16 coarse allen head set screw at that location you wont have to pre drill the hole.Just run the tap down and install the plug,then drill out the orifice in the plug.A /16 long set screw length works good .Just tap out about 6 threads.As for the accumulator plug in the valve body that mod is good but leave in the 2/3 cushion spring so you dont snap the 2nd band lug off when manually shifting to 2nd.The spring also absorbs 2nd servo apply oil.Many people weld the band lug so this doesnt occur but leaving in the spring is the real answer.It wont affect shift timing because the intermediate clutch pack and intermediate band are both used in manual 2nd but the purpose of the band is to provide engine breaking by grounding out overrun when the output shaft becomes the input member when lifting the throttle.

 

[jakeshoe]

Chris,
Can you show the front pump cover slot you mill.
We've spoken about it before but I've never been sure what you are connecting the vent to.

Jake

 

[Gregaust]

Can i ask? What benefit is this converter feed mod??

 

[87buickracer]

Thanks guys!!
Question for chris.Your point on installing the 2-3 accumulator spring,would this hold true for automatic/manual valvebody with set screw in place?

 

[Alky V6]

Can i ask? What benefit is this converter feed mod??

Maybe someone can post a pic of their wiped out crank thrust.

 

[87buickracer]

If you use a 5/16 coarse allen head set screw at that location you wont have to pre drill the hole.Just run the tap down and install the plug,then drill out the orifice in the plug.A /16 long set screw length works good .Just tap out about 6 threads.As for the accumulator plug in the valve body that mod is good but leave in the 2/3 cushion spring so you dont snap the 2nd band lug off when manually shifting to 2nd.The spring also absorbs 2nd servo apply oil.Many people weld the band lug so this doesnt occur but leaving in the spring is the real answer.It wont affect shift timing because the intermediate clutch pack and intermediate band are both used in manual 2nd but the purpose of the band is to provide engine breaking by grounding out overrun when the output shaft becomes the input member when lifting the throttle.

anyone else using 2-3 accumulator spring after performing mod to valvebody.I thought that once mod is performed the spring serves no purpose.

 

[Gregaust]

Maybe someone can post a pic of their wiped out crank thrust.

Thanks Don ..

 

[chris718]

it also cushions the band apply.2nd servo oil strokes the piston

 

[Gregaust]

Maybe someone can post a pic of their wiped out crank thrust.

Can i ask is this just a Buick prob or common to other motors also ??:redface: Is this beneficial for all T.400? Is it the extra pressure pushes the converter forward that wipes the crank thrust?? I've just not struck this before ..Thanks

 

[Alky V6]

Can i ask is this just a Buick prob or common to other motors also ??:redface: Is this beneficial for all T.400? Is it the extra pressure pushes the converter forward that wipes the crank thrust?? I've just not struck this before ..Thanks

This is not just a Buick problem. The mod should be done to every T400 as a safeguard. Yes, you're right about the pressure pushing the converter forward. If you would like more info on this, do a search for past threads on the subject of crankshaft thrust problems, failures, etc. I know I've posted my share on the subject.

 

[Gregaust]

Ok , will do Don..Thanks

 

[turbobitt]

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.

Don,
I was touring poland and havn't had a chance to respond. I bought a Stange yoke for this housing. You will fing it listed in this link, P/N U1664N
Strange Engineering Catalog
This is a nice quality yoke and not just a forged yoke that was hardened.

 

[jakeshoe]

Don,
P/N U1664N
Strange Engineering Catalog
This is a nice quality yoke and not just a forged yoke that was hardened.

It states the yoke is the same yoke as PN U1664 except it is case hardened for roller bearing use.

What makes you think it's not "just a forged yoke that was hardened"?