[tooski]

There are two accumulators on the TH350 . One is on the case outside near the tail. The other is installed in the valve body and covers the band apply servo. The valve body accumulator spring was missing when I disassembled it. (I think but can't quite recall but the cover the spring rides against was installed upside down.) I'm in the final stages of reassembly. What detrimental effects does leaving out that spring have? I cannot find that spring on line.
I'm not sure how that system operates, but it seems to me that the spring is used to build pressure on the oil that enters the chamber between the accumulator and the band servo.
Frank.

[Cliff R]

Accumulators are used to soften and/or delay the shift slightly. They are in route with the fluid path to the apply piston in a clutch drum or to a servo that applies a band.

The factory was very careful with accumulators so they didn't get customrer complaints with excessively hard shifts but still didn't soften them up enough to have accellerated friction wear.

It's common practice to leave out accumulator springs or disable the accumulators all together to shorten and firm up shifts. Many builders also increase line pressure and flow to the clutch drums at the same time. So it's more of a "recipe" than just modifying one part. The end result can vary dramatically depending on line pressure, separator plate hole size and accumulator function (or lack of it).

So there is not direct answer to your question other than leaving out the spring and doing nothing else will shorten and firm up the shift some.

I'd add here that torque converter efficiency plays a HUGE role in overall shift firmness. Higher stall and/or looser converters will end up with softer shifts than a full size efficient stock type converter. all else being equal........

[tooski]

Thanks much, Cliff.