Modified 67 Riv - combo critique

https://www.summitracing.com/parts/hup-gm20bpo

It’s a 2000, not a 2200 (sorry-fatfingered it). It’s designed for the torquey B O P engines.
Patrick

 

I have been running the same converter you have in your Riviera for years. Maybe its a freak but I have no complaints so far. I would at least get it working and try it before tossing it.

Bob H.

 

Thanks Patrick and Bob. I'm considering different options including making what I have work whether it's the PAE 1400/4000 or the stock switch pitch. What do you fellows think about the 2500 stall torque converter offered by TA Performance?

 

Found this bit of info on the forum, do you think this is generally true?

"11 converter ST300 2-speed has a low stall speed of approximately 2300-2500 rpm. High stall speed of approximately 2800-3000 rpm.
12 converter in TH400 3-speed has a low stall speed of approximately 1800 rpm. High stall speed of approximately 2600-2800 rpm."

supposedly from this site but it appears to be defunct now: http://www.442.com/oldsfaq/oftsp.htm

If true, defaulting to high stall might work as well as an aftermarket unit...just a thought. Might just slap the stock 12" s/p converter in and use the money on the headers, interior, etc.

 

Definitely the variable pitch, functioning either as designed or with a controller like Larry mentioned. I run the smaller ST300 converter with a microswitch on the column shifter, but at a stop with my foot off the accel pedal it automatically energized high stall, which is built into the original design. Super nice when running a lot of cam, as the looser high stall doesn't lug things down too much.

For casual driving I don't use the shifter switch. When it's time to go I just step on the pedal and she goes from high to low stall as designed. My trans is a manual shift TH400 converted to variable pitch, so I don't need the detent switch next to the carb anymore. The little switch that gives high stall at closed throttle is behind the carb at the end of the long rod towards the firewall.

Getting a '67 chassis manual will help a lot. In the meantime, here are some illustrations.

The carb switch gives you detent (downshift) when you mash the pedal as well as high stall. I think high stall comes in earlier than detent if I remember. The other little switch at the end of the carb linkage rod gives high stall at closed throttle.

And sorry, you can't use a fixed pitch TH350/TH400 converter in a variable pitch trans without changing the trans front pump, input shaft and a few other things. Trans would be coming out for this.

And I don't suggest hotwiring for high stall constantly...the solenoid that controls trans fluid flow for high stall would be energized 12v+ at all times, and it's already running hot inside the transmission. Don't know how long that would last. Detent and downshift solenoids probably weren't designed for long term long term energization.



Devon

 

Thanks very much for the pic! I think running the original switch pitch is my best option - wish the car came with the switches and brackets still installed, who knows where the last owner put them. I'll figure out a way to make it work. Now....time to order headers.

 

Here's the update gang,

1. Got the new headers on and hooked up to the exhaust
2. Got the Edelbrock intake on and the s-divider off
3. Got the stock switch pitch in and that PAE one out
4. Wired up the switch pitch and the kickdown

Had one small hiccup of severe bogging and what felt like a misfire that turned out to be one very poorly gapped spark plug. But WOW, a substantial improvement in driving and performance. I have a nice new Holley 950 and will be experimenting with timing still. Thanks for the suggestions.