1-2 accumulator

[Turbo F-bird]

Just checking the current thinking on whether to block the 1/2 accumulator off or use the heavier spring most shift kits come with. I've done a lot of searching here and read the CK book but I'm not seeing a common train of thinking on it.

My trans shifts nice and firm, has a shift kit with a functioning accumulator and a 10" 2800 stall converter which is a tight converter not a loose one. The CK book says over 400 HP to block it but I saw posts saying they no longer do that, with a loose converter you should block it to maintain shift feel, with a tight converter you'll break the band lug or other stuff, etc. My engine made just shy of 400 rwhp and should surpass that after I swap out the injectors and bump the boost up so I'm getting paranoid of hurting the band as the power increases. So what's the current thinking these days? I'm a little confused.

 

[wickedtt]

I say block it.

 

[chris718]

I block every 1 I build when it has my servo assembly.Without a bleed in it the newly engineered piston is slightly slower to react to lower apply pressures present at part throttle eliminating the bang.This allows large feed holes to supply the inner piston with no side effects.The cushion spring functions as the 1/2 accumulator and takes shock loads off the band struts.Many have questioned my use of the dual seal ring instead of the lip seal on the apply side.This is where I burp the oil out of the servo when the circuit is off snd air fills the cavities which can cause mushy initial servo apply before the air is displaced by intermediate servo apply oil.@ 3.005" diameter it is the largest servo available for the 2004r.The cover is stretched so far it uses an o ring 1/2 the diameter of the original.More stuff to be pirated.With any other servo it will be bangy,Aquick reapply on a 3/2 kickdown is also part of the design.Too much power and the trans will go back to 1 on a 3/2 with hi power.This is where the proper design of the 3rd acc side of the pistom comes into play.Also the band is applying in a different way on a 3/2 in comparison with a 1/2 ratio change.

 

[Turbo F-bird]

Thanks for the replies. I had the CK servo in my 87 Turbo T and it was a phenomenal piece! The difference in shifting was like night and day.