I have a variable/switch pitch th400 that came in a 70 442 I bought last fall. I have freshened up the engine and have done some performance improvements, now the convertor has seemed to take a dump on me, it has PAE 3000 04 06 stamped on it. my question is what need to be done to convert this to a standard non variable pitch transmission. the current engine combination is probably in the 475-500 hp range.

 

You have to change the converter, the front pump, and the input shaft. You also need to remove the special 1/4" diameter plug with the orifice hole in the case at the pump mounting face.

 

By the way, if you decide to do this, I'd be interested in buying those parts from you.

 

I'm confused as to why you want to eliminate the switchpitch. Why not just replace the convertor? They're still available. Get one of Bruce Roe's electronic controllers while you're at it.

 

well I drove the car again today. the convertor was working as it is supposed to for 1 pass, then it no longer would go into hi stall mode, solenoid clicks but does not loosen up. so then I made a pass in lo stall mode, trans has a lazy 1-2 shift then a ok but not great 2-3. I have the convertor off a two position switch on the shifter one position for convertor one for line lock, launch car, rpm reaches 4500-5000 lock convertor then 1-2 shift, this is what I understand is the preferred method of drag racing with a switch pitch according to the buick guys. there isn't much info out there of people drag racing with one of these units. seems like what I have read 500 hp and a switch pitch is not very reliable, this is a street car but it will be abused.
if someone is interested I would swap for a good bop th400 if it had good parts in it.

 

forgot to mention the convertor is a 12'' unit.

 

How do you get that plug out. Thanks Bob

 

Which plug? The 1/4" one with the orifice hole?

If that's your question, just enlarge the hole sufficiently to screw a sheet metal screw into the plug. Use a slide hammer to pull it out. Use grease on the drill bit and the screw to contain metal filings.

 

Hi Joe, Took your advise on removing that plug. Worked perfect. Thanks so much for the help. Do the old parts have any value? Thanks Bob

 

Well, I'd certainly be interested in buying them. I'd want the pump, input shaft, and converter as a set. You can contact me directly at joe_padavano@rocketmail.com if you're interested.

 

The switch pitch parts came out of a 1967 442. The torque converter id still attached to the engine. I'll take it off this weekend and forward photos. If you have any questions email me at pro67442@aol.com

 

I need a converter for one of my spare switch pitch th400s some day, purchased from the late, great, Ed Skaff.

 

Not hijacking, but is the convertor from a ST300 the same as one from a turbo 400?

 

Yeah, you kind of are...

No, but you can use the JT converter in the TH400 for a slightly higher stall speed. This is the old trick.