Torque Converter Confusion

[C9]

Gettin' a little confused about what fits what.

455 Buick.

I found a couple of converters at Summitt that indicate they are for T-400's.

They also say "For Chevy" in the details section.

Along with that a dual bolt pattern flex plate is required.
This part is not a problem as my new flex plate has dual bolt pattern.


My 32 has a B&M 2400 rpm stall.
I found it at Pep Boys, they had a great price on them and all I remember seeing on the was, "T-400."
Slid onto the trans ok, bolted right onto the flex plate, no probs.

Am I correct in assuming that any converter labeled "T-400" will fit my 455 Buick and the Buick T-400?


Along these same lines I'm looking at getting a Chevy T-400 for spare internal parts in case my B-O-P core needs some things.
I don't believe there are internal parts interchange problems between Chevy and B-O-P.

The Chevy T-400 is out of a pickup and was working ok.

Don't know the history of my junkyard T-400 B-O-P core other than it's a short shaft and pretty clean.
(The salvage yard doesn't clean anything fwiw.)

[wayne petty]

everybody who messes with transmissions might choose to download this 176 page torque converter catalog....

it has pictures also...   kinda like a mc donalds menu...

http://www.kingomatic.com/documents/08_TC_Cat_lo.pdf

be sure to save it... and to check out the back starting at page 163...

sorry that there are not any applications... but this is the best converter catalog i have seen....   lists them all ... pictures front and back... bolt circles... pilot diameters... some oe stall speeds listed...  
and all the other info... worth its weight in atf..

[enjenjo]

Unless Tony tells me different, there  is no difference in fit from Chevy to Buick on torque convertors. Now there are internal differences in the trans itself, in the valve body, but you can change them from one to the other as long as you include all needed parts.

[Deuce]

there  is no difference in fit from Chevy to Buick on torque convertors.

Mostly true ... if you discount the Switch/Pitch converters.

We have a guy here who runs a Torque Converter Service and he can cut a converter and make it to use with your own combination. He needs to know the weight, the size engine and gear ratio. Then you tell him what you what it to do ...

He has about a half a dozen employees and ships nationwide. He must be doing something right  

Lots of fellows around here use him ...
I had him cut a converter for my 32 roadster with the Switch/Pitch and also one for the 1932 3W with the 700R4 ...

BOTH work great ...  

[Crosley.In.AZ]

There are 3 basic t-400 transmission variations.

1964 is all by it's self on the t-400.  Same basic internals , the valve body & rear band  servo area is slightly different.


Switch pitch converter t-400 .. pump & stator support , input shaft are special.. case needs a port in it and usually a small plug in the port with a small hole in  the plug.   Buicks , Caddys used this trans.. Not sure about a Pontiac.. ?


The regular  t-400 we all know.   A  few internal changes here and there on the hard parts , valve body area , check balls,  minor stuff.

The  difference in the Chevy and Buick converters  can be how they bolt to the flex plate.  Nut and bolt or bolt only.  3 pad or 6 pad bolt up pattern

Diameter are slightly different too. Usually a 13 inch converter in a t-400.

A t-350 non lock up converter simply slides into the t-400 trans.  Spline locations , size are the same.

We sell a t-400 stall converter listed as a BOP unit....  

[C9]

Seems like this hot rod stuff is getting more complicated, but I don't think it's me as much as it is more info in the catalogs - which is good.


Wayne, downloaded and saved the catalog.


Thanks Frank.
Thought I had it figured out last time I asked.


Deuce, is that the old style switch-pitch?
Don't they hit pretty hard on a launch?
Even at half throttle?

My 2400 rpm stall converter flash stalls @ 2800 rpm and hits pretty hard.
Chirps the tires at light throttle settings at the start if you're not paying attention, but generally drives pretty well.
Even better in fact since I went from a 3.70 diff to a 3.00.
(30" tall tires.)


Tony, good to know in case I have to steal parts from the Chevy core trans.

Who makes your B-O-P converter?
T-350 type with smaller diameter?

I've heard Continental is a good brand and was used quite a bit in my pal's trans shop in Ventura.
Some time back so who knows if Continental is still in business.

What's the price for your converter?

And who do you like for rebuild kits?
Summitt has several choices.


If I learn to rebuild a T-400 and buy an industrial sewing machine as well as learn how to use it I'll have a fairly complete group of skills for building the next car....

Thanks for the info guys.
A big help it is.



One thing I thought I'd pass on.

The PITA diff swap a few months back was complicated even further by front yoke issues.
Turns out it's a small yoke T-400 and the local driveline guy - big Buick enthusiast - tells me it's a Buick only 1968 trans/driveshaft issue in that one year only.

Live and learn.... :?

[Deuce]

Deuce, is that the old style switch-pitch?
Don't they hit pretty hard on a launch?
Even at half throttle?

That is the beauty of the Switch/Pitch ... you have two different stall levels to choose from. My 32 is very tractable ... unless I want to flare the converter ... but I do not have the torque that your big Buick has.

I have mine set up on a toggle switch. I run it in high stall most of the time ... with no problems. What I really like is the fact that when I pull it down into gear ... there is no clunk. It is loose enough to not bang the car and when sitting at a traffic signal ... it just sits there. NO dragging the roadster thru the intersection like with some cars.

When I head out on the open road, I just flip the switch ...

[C9]

Deuce, is that the old style switch-pitch?
Don't they hit pretty hard on a launch?
Even at half throttle?

That is the beauty of the Switch/Pitch ... you have two different stall levels to choose from. My 32 is very tractable ... unless I want to flare the converter ... but I do not have the torque that your big Buick has.

I have mine set up on a toggle switch. I run it in high stall most of the time ... with no problems. What I really like is the fact that when I pull it down into gear ... there is no clunk. It is loose enough to not bang the car and when sitting at a traffic signal ... it just sits there. NO dragging the roadster thru the intersection like with some cars.

When I head out on the open road, I just flip the switch ...

Sounds like a great way to go.

The big ol Buick is fairly predictable.

A few times I've hit the throttle a little harder than wanted, the engine responds very quickly and bangs the converter.

Shifting into drive or reverse the converter doesn't 'clunk' into gear.
Idle with dual quads or single 4 bbl is 600 rpm - with big or little cam.
Pretty civilized little car if I do my part.


Silly as it sounds, and the car has fairly good ergonomics, if I'm wearing boot type footwear it can be a little more difficult to drive.

Fairly soft soled tennies/athletic shoes work well.

Best ones are a pair of "Pit Shoes" I bought from Summitt several years back.
Very light, smooth soles.
Only drawback to wearing these is, if I'm going to do a lot of walking I need to bring another pair of shoes that are good for walking.

The quick responding Buick engine - and the 31, even with dual Carter 500 cfm quads and bigger cam should respond just as quickly as the 32 does with its mild cam and single 750 Edelbrock.

Aiming for 10.0/1 CR on this engine vs 9.0/1 CR on the 32.

I think it's a do-able deal since the Buicks usually run a maximum of 32* all-in on the mechanical.
And I hear that some of them run as low as 28* all-in.
87 octane year-round, no detonation etc. probs with the 9.0/1 CR 32.

Gotta change your thinking sometimes, but . . . if it works....