Not seeing any mention in the 600HP transmission thread pertaining to accumulator piston and sealing rings, at what point do they need to be upgraded to a billet piston?I have, hopefully an 800hp big block w/a transbraked 727 trans. Both the front and rear servos are billet. With the accumulator blocked with an aluminum rod,it doesn't seem like it has much of a job left. Will a good stock accumulator work here? Thanks, Bill

My car runs 9.O-9.1 @ 3350lbs. The stock parts are; servos, accumulator, input and output shafts, pump gears sealing rings. 3 pin planet carriers. It has 750+ passes with these components unchanged. Current clutch frictions and bands have over 400 passes. What has failed in 750 passes? 2 stock front planet carriers. One I caught on inspection. One stranded me. Cured with a steel planet carrier. The aftermarket aluminum rear clutch carrier had the clutch hub splines pull thru it. Easily remedied by adding a snap ring to protect the aluminum from wear. This failure stranded me. Wore out 2 reaction shaft support ring grooves and sealing rings. Cured by lapping the ring grooves in the support. This was caught during inspection. So in 9 years it's stranded me twice.
Doug

Thanks Doug. Your car is a strong runner as well as being super clean. I appreciate the real world input from those with the actual experience. Just want to spend money on necessary items, not a "trick of the week" fan. Bill

IMO, the only time the accumulator piston needs upgrading is if it's plastic.

I put a billet dual seal accumulator with blocker rod in my 727 just because it had the Billet Servos too with the dual sear rear servo.
I think the stock aluminum accumulator piston with blocker rod would have been fine.

From Front to back:
Custom 9" Ultimate Torque Converter
Cope Max Lug Pump with modified startor support. Vent Pluged.
Billet Steel Front Drum, Alto Red & Kolene Steels
Billet Aluminum rear drum, Alto read & Kolene Steels
Lightened Sun Shell
Billet 4-pinion steel front gear
Factory Rear gear and input/output shafts
A&A Super sprag
Modified support and sprag oiling, with rear case vent
Sonnax Super hold Billet front servo kit, with 4.2:1 lever and the thick band strut and adjustment anchor on a kevlar flex band.
The Dual seal accumulator, I think it is a Cope part?
The "Shift" reverse super servo (Dual seal.)
Cope Manual Reverse Valve Body
Cope Aluminum Deep Trans Pan

There's some other stuff I likely forgot?

Thanks all, Bill