Installing turbo 400

[Buickforlife]

What all is involved in installing a t-400? Will the same flywheel work? I know the driveshaft might have to be shotened and the transmission mount might have to be moved but what else?

 

[YouLikeThat]

If I remember correctly, Shifter detent plate, shifter cable and or the shifter cable bracket( trans side) , filler tube, along with what you said, Drive shaft and transmission mount.
The factory flywheel will work just fine.
I just went back to an OD but if it doesn't hold up I'll be going back to a 400 without even thinking about it.
SR

 

[Buickforlife]

If I remember correctly, Shifter detent plate, shifter cable and or the shifter cable bracket( trans side) , filler tube, along with what you said, Drive shaft and transmission mount.
The factory flywheel will work just fine.
I just went back to an OD but if it doesn't hold up I'll be going back to a 400 without even thinking about it.
SR

Thanks for the reply, I was thinking the flywheel would work, but wasnt sure. I'm about to switch it over to the turbo 400 as soon as i can get a new converter. I am tired of breaking these 2004rs.

 

[Buickforlife]

Well I completed my turbo 400 swap. I took the driveshaft to be shortened, and just got it back. Will get it all buttoned up tomorrow, and test drive it. Have any of you had a problem with the vaccum modulator on the turbo 400 getting boost to it and breaking the diaphram? I was kinda thinking about putting a check valve in there just in case.

 

[streetknight]

subscribing.....

what did you do about a mount?

 

[DoubleD]

I used the HR mount on the stock crossmember. it went in, but it was tight.

and I also installed mine with a RMVB and a brake, so I didn't deal with the vacuum modulator... I would think you would have some issues with it on a boosted car, and seem to remember some posts on here about doing something to it.

Great help I know, but I think you could find it in a search

 

[pacecarta]

this comes up a lot .. a search would have found you the answers

you can use the 2004r mount , just need to slot the holes outward to bolt to the th400
trans crossmember for the 2004r works fine and can stay where it is ,
driveshaft needs the th400 yoke and usually an inch shorter (50 1/2 center of ujoints ), if going with a t-brake 400 id recommend a custom moly 1350 ujoint driveshaft and a 1350 forged or billet pinion yoke

as for the governor , runa check valve , better is go with the manual VB which doesnt need one , it wont be automatic but your shifts wont be right in auto mode , i went with the Reverse manual valve body with tbrake

youll need to do the speedometer gears , think i did 15 on the drive , 39 on driven for 28" tires for 3.42 rear

if you stay wih stock shifter gbodyparts.com sells a shifter detent bracket for the stock shifter ,
i ditched the stock shifter for a b+M quicksilver which also took care of the cable breaking issues of the crap aftermarket cables and also comes with trans brackets and shifter arm

youll need a converter for the th400 with anti-balloon plates built for turbo application and torque converter bolts ( some use through bolts but you wont be able to use your 2004r stock bolts )

if you didnt get the trans from a turbo buick trans guy do a search on cooler line pressure restrictor and thrust bearing failure because of too much cooler line pressure.

for cooler lines you can bend the ones from the 2004r , and dont forget the aux trans cooler ...i went with -6an lines routed through the frame to a derale thermal switched fan cooled aux cooler

 

[BadAssGN]

If you want to have perfect shifting there is a cable operated Modulator that
came with a 6.2 Diesel application.

 

[SSedan64]

There's a Pic of TransGo's Part# VBP-VAC / Vacuum/Boost Bypass Kit for the Modulator on Pg. 5 in this Thread> http://www.turbobuick.com/forums/transmission-talk/255286-th400-build-pictures.html

VBP-VAC>> Tough Stuff

 

[87buickracer]

There's a Pic of TransGo's Part# VBP-VAC / Vacuum/Boost Bypass Kit for the Modulator on Pg. 5 in this Thread> http://www.turbobuick.com/forums/transmission-talk/255286-th400-build-pictures.html

VBP-VAC>> Tough Stuff

I run this along wth h+r parts poly trans mount and had a custom driveshaft built or you can just shorten yours..I run automatic transmission and it shifts perfect and smokes the tires in second gear.For the price,you can't be the transgo bypass valve.I will probably buy another just to keep in the tool box....very fun to drive on the street..I have been beating my th400 tranny for almost a year and clutches look brand new,I couldn't believe it..I ran the fluid for about 4 months on a fresh build before I changed it too..

 

[streetknight]

if you use the trans go by pass thingy.

Can you set the governor up to designated shift points or still have to make the shifts yourself.