Who can explain me the difference in transmissions?

[Guest Rob J]

In my ongoing quest to gain more personal info on these cars, I'd like for someone to clarify the real differences between a GS "BS" coded transmission, and the standard 65 Riviera transmission on non GS cars.

I've searched, and have read conflicting information, so I'd like to clarify it once and for all.

Also, did the term "Super Turbine 400" specifically designate the BS coded transmissions, or both of the transmissions in the 65 Riviera.

One more thing. Explain to me the "Switch Pitch" functionality.

I'm sure the experts here can give it to me clearly.

Thanks, Rob.

Edited November 21, 2010 by Rob J (see edit history)

[JZRIV]

Rob,

The Super Turbine name was not specific to the BS or BT, BR etc. The BS tranny had slightly higher shift points and a modified valve body for better shifting under heavy acceleration. I never actually saw exact specifications though to know for a fact.

The "switch pitch" or "variable pitch" terminology is a torque converter with two different stator angles that changed back and forth from low to high angle and vice versa depending on throttle position. It was an excellent design to help launch a heavy car in a hurry but yet didn't have a tendency to allow the car to creep when at idle. Of course the pump assembly was different and there was a solenoid inside which redirected oil to change the angle so the differences are not just relative to the converter itself.

[RivNut]

Here's a link to TeamBuick.com's site and a list of all of the TurboHydro (ST) 400 transmissions. You can see that the BS code was also used in '66 on all Rivieras. In addition to what Jason sayid, it looks to me as if the speedometer drive gears in the transmissions may also have something to do with the coding.

Team Buick Reference

[1965rivgs]

Hi Rob,

As I explained via the telephone the BS coded trans had a different governor and valve body which resulted in higher shift points at full throttle. Buick used this trans code designation right up thru the later GS cars for their high performance turbo 400.

All `66 Rivieras did NOT use the BS coded trans. Standard Rivieras used the BT coded trans. Only the Riviera and Wildcat GS cars were built with the BS coded trans...and I have found exceptions to this documented via build sheets. The internet is much the same as any other media outlet...just because you read it in the newspapers (or the internet) doesn`t mean it is true!! Be careful, there`s much bad info out there. :eek: Nothing beats crawling over and under the cars for a couple decades...the cars themselves represent reality.

Tom Mooney

Edited November 22, 2010 by 1965rivgs (see edit history)