Buick th400/ Chev th400

[mr hemis lemopar]

hello,

recently purchased a 66 401 w/a th400( is the buick 400 tranny considered a turbo as in chevy turbo 400??). does anyone know how to rebuild said buick turbo 400 and have it perform similar to a chevy turbo w/a shift improvement (B&M) kit. for instance fast, hard shifts w/o hesitations or lags? i've been told it is as simple as finding a donor chev th400 and swapping its pump/convertor& etc into the buick tranny. has anyone done this? is it really this simple? what are the specifics?
thanks in advance for any/all responses.

[Bob]

Have a look in the reference section library. The '66 shop manual has all rebuild instructions in it.

They are basically the same tranny, but the Buick version is twice the performance transmission than the Chevy ever thought about being. It has a switch pitch converter with a 2500 rpm high stall. A plain chevy th400 never had a chance.

[mr hemis lemopar]

Bob,

thanks so much for taking the time to comment. as you can probably tell by my ???'s that i am a new "Buick guy"( always been intrigued but never had the opportunity). the engine/tranny setup i purchased has been stored outside for what looks like 100 yrs and needs a total/total rebuild. the 401 i intend to go completely through (new everything if needed) at stock specs, while the tranny is another story. is it possible to modify the tranny to eliminate the slight lag between gears?

also i would love to use a multiple carb setup. 3-6 deuces or twice quads . do you know what compression or cam mods would be required to run said setups?

once again thanks in advance for any/all comments.

roger

[Bob]

I am not a transmission expert, but I think the Buick 400 is as good as you can get. The only reason to change would be for an overdrive.

There should be no "lag" between gears. If it has one, it is probably in need of a rebuild. You can put a kit in it to make it shift as hard as you would like any automatic to shift.

[bobc455]

If you do pursue a shift kit, I'm very happy with my TransGo shift kit.

People who have used both B&M and TransGo recommend the Transgo.

-Bob Cunningham