I have a '70 442 ...

I saw a post where a guy mentioned messing with a switch pitch trans ...

Will a th400 switch pitch trans fit my eng ...

Which one ...

My last car with one was a 65 Buick GS ...

 

Yes, a TH400 switch pitch transmision will fit on your motor. You can even convert a non switch pitch 400 to a switch pitch. They sell some after market part to do this. I do not know who sales it though.

 

What is this "switch pitch" ? Never heard of it. Chumley

 

Not much more than a different torque converter and and pump.

Cal-Tex Automatic Transmission Parts
5923 Kester Ave
Van Nuys, CA 91411-3016
(818) 994-9947

Changes converter stall (1800 to 2500, for instance) with the "flip" of a switch.

Norm

 

There is a throttle linkage that increases or decreases stall speed ...

I put a switch inside the car that I could flip ...

My friends were impressed when I would torque brake the engine and flip

the switch and the RPMs' would go up and down ...

It almost works like a six speed ...

 

Not quite. There is an electric solenoid valve in the trans that routes hydraulic pressure to a special torque converter. This converter has a moveable stator (now THAT'S an oxymoron) that can change the angle of the stator vanes, hence the term "switch pitch". Changing this angle changes the toruque multiplication and stall speed of the converter.

I did this conversion back when Kenne-Bell was selling the conversion parts. As Norm pointed out, it pretty much involved swapping the pump and converter, in addition to adding the second solenoid valve and wiring. One cool thing you can do if you have a lumpy cam is to operate the converter pitch from a switch on the brake pedal. This way, when you're stopped in traffic the stall speed goes up to make idling easier.

 

I can usually get a "Ick" tranny from pic a part for cheap and they are usually behind a big block, has to past nailhead so '67 on ...

 

The factory setup works just like that. At idle, the switch is on high stall to minimize creep, as soon as you touch the gas it goes to low stall for efficent part throttle response. High stall is again activated past 2/3rds throttle for passing acceleration short of a downshift.

Both my Olds' have factory switch pitch TH400's

 

Kind of resurrecting a pretty old thread here, but my question is, when pitch is switched at the 2/3rds throttle setting, is it noticeable? I don't have a tach and can't really seem to determine if I can feel a noticeable change. I know my switches and solenoids are all working and I can definitely tell the difference at idle but not much at the 2/3rds setting.

 

Does energizing the solenoid cause the higher stall speed?

 

Yes energizing the solenoid gives high stall. To answer the other question, yes it's noticeable. At least mine is. I particularly don't like it in high stall at any speed other than low speeds. It feels like the trans is slipping due to the higher stall speed. As Joe said I prefer to have it on when stepping on the brake and then come off at a predetermined time past that. There is a member here, Bruce Roe, who makes a delay switch with several other features