Kid Thunder

Joe Pad,
Whey do you think Olds choose to use the switch pitch only for 3 model years?
Cost, fuel mileage, the advent of the Turbo 350 or what ever. It makes a world difference in the way my 67 Cutlass 330 2bbl Jetaway trans runs. Much easier in around town stuff & in all out running. It's like having 2 torque converters in one transmission!
Don-M

joe_padavano

Four model years, actually - 1947-1967. I don't know why they dropped it, except possibly because the increasing HP and torque of the late 1960s made the switch pitch redundant. Note also that the 1961-63 Olds transmissions like the RotoHydro5 in my 62 F-85 had a similar method of providing an additional "passing gear" by alternately using then locking the fluid coupling while in second.

jaunty75

The new math.

jensenracing77

My transmission guy said it was a money thing. He said the gain was not that big of a deal to the general public and not worth the extra in manufacturing.

joe_padavano

Well, 1947 is ALMOST 1964...

I'm sure that was a very big part of it. I can't really see the need for a switch pitch torque converter when you have 500 ft-lbs or torque. It actually makes a lot more sense for a radical cam. I built a 71 one time and used the switch pitch wired to the brake switch. With your foot on the brake, the converter went to high stall, making it easier to sit with the trans in drive. A separate switch also allowed you to select the high stall for launching the car off the line.

Kid Thunder

You are right Joe, with 500 lb-ft of torque it's not needed but with a 330 2bbl it sure comes in handy!