I'm in the process of installing a Turbo Action Cheetah automatic/manual valve body in my 727 (big block). I bought the valve body at a swap meet and it didn't come with any instructions so I downloaded them from the Turbo Action website. I'm at the step where it says to remove the accumulator spring and also a second spring under the piston if there is one (there isn't). I know if it says to remove the spring in the instructions that TA wouldn't say to do so if it wasn't necessary but it made me wonder what happens with the piston if the spring isn't in there. So I have been looking on line for information on the spring removal and it's a mixed bag of answers. Some say run without it as TA suggests while others say leave it in if it is a street application as it is harder on the trans. without it. What is your opinion on this? Should I leave it in or do as TA says and take it out? There's also talk of using a blocker rod if the spring is removed but I get the impression that that is more relative to race applications.

https://www.turboaction.com/17676%208-17-08.pdf

If you pull the spring you should install a blocker rod . Me personally, street car I'd leave the spring in. If you want a real hard shift leave it out, it only affects one shift

With a loose converter I would remove the spring and block it down. With a tight, stockish converter it will bark the tires when it shifts 1-2 without it. Clutchflite? Brutal, just brutal either way.

If you can find the time to read this, it may help w/ your decision: https://board.moparts.org/ubbthread...me-to-fluid-flow-schematics-for-727.html

Accumulator function is to cushion the 1-2 shift.

Race car, race car with tags, chirp the tires shift - leave the springs out and use a blocker rod.

Street car, cruiser, mild mods, don't want your teeth rattled - leave it in.


Some valve bodies don't even require the piston to be there.

The bottom line is:

the outer accumulator spring serves only to cushion the application of the front clutch and has no function on any upshift.

I guess I'll leave it in. Don't really want hard shifts nor care about chirping the tires but does leaving it in defeat the purpose of using this particular valve body? Would I be better off just leaving the factory valve body in the trans.? Engine is a 400/470 stroker.

With this in mind what was causing the harsh shift I had in my 2000 Ram ? I had a billet acc piston and blocker rod, and the shift was really harder than I liked, when to took out the blocker and put the spring back the hard shift was gone? I can't remember which shift it was , want to say it was 1-2 , I haven't driven that trans in a decade but it will be finding a new home in the Ram I bought earlier this year when I turn the Cummins up a little in this one.

You are still getting the benefits of the valvebody so I would swap it. It's not a big deal, to me anyway , to drop[ the pan and valvebody so maybe run it without the spring and add the blocker and if it's too harsh take out the blocker and put in the spring ? If you have a pan with a draain plug using a clean catch pan you can recyle the drained fluid.

And for god's sake don't put that ATF+4 shift in the trans.

Ran +4 in my built 47RE. I even run it it my 904 in the race car

Once again, the outer accumulator spring DOES NOT cushion any upshift...it's an old Mopar myth. Spring or no spring, as long as the accumulator piston is free to move it will cushion the 1-2 upshift.

What is actually accomplished by pulling the springs and blocking it? I wouldn't do one without the other. Haven't done a stock rebuild in years. Only race stuff with a good VB. Piston with blocker in all of them.

The accumulator does affect the 1/2 shift. Removing the outer spring without blocking it hammers the accumulator piston, I have seen them cracked from this, why would you remove it without blocking it? Some of the performance transmissions had an inner spring on the accumulator to hold it down from the factory. Moral to the story, if you remove the outer spring, block the piston.

I’ve taken them out before and had no issues with the trans. Did not do the blocker rod.

This effectively cancels the cushioning function of the accumulator...makes a firmer 1-2 upshift but risks damaging the rear clutch.

How can it damage the rear clutch when it is already applied in all forward gears? The only thing happening on the 1/2 shift is the front band is applied unless you manually shifted from 1st to 2nd with an auto shift valve body or a rear band apply manual valve body. In which case then the rear band is releasing on the 1/2 shift. At no point is the rear clutch released and re applied, it is constantly applied 1/2/3.
What damages the rear clutch is shifting from reverse to drive without coming to a stop. Effectively using the rear clutch as a vehicle brake.

That has been my understanding. Get the band applied more aggressively. Just wanted to make sure I wasn't missing something. Everything I've done in recent years has been race units, Accumulator is made non-functional.

Years ago, we would do that on our hopped up street cars. With the manual Cheetah VBs, blocked accumulators and the ever present overlap, it could be obnoxious just cruising around..

The accumulator outer spring cushions the initial application of the rear clutch i.e. from N to D or 1. Without the spring, the rear clutch piston applies harder and can overwhelm the Belleville spring causing it to break or pop the piston out of its bore.

I can see where if the spring was just removed and the servo wasn't blocked that, that may be a problem, but since there is line pressure above and below the accumulator servo they should cancel each other out with the servo blocked. I can also see where increased line pressure could be a problem, or throwing it in drive while on fast idle or a neutral drop would cause that.

I'm other way , I don't run + anything in my built 47RE .