Accumulation for 2-3 through the servo?

[85 Riviera]

On my 325-4L (that is similar to a 200-4R) I have done a few cheap mods to improve shifts, I got the 1-2 doing nice with just limiting the amount of accumulator traval by putting a spacer on the shaft that holds the piston in place, the spacer is on the oppisite side of the spring. That really helped the 1-2 shift that was kinda sliding before now has a good solid push into 2nd. 3-4 was improved by flipping the accumulater spring and piston 180 degrees. Now heres what I am thinking about but I need some help, I want to improve the 2-3 shift alittle through the servo, I know the servo acts like a accumulater for 2-3. I got a picture of the insides of a servo with index of the parts name so that we can speak the same langish Click here To See Servo I have a few servos just sitting around my garage with different size apply pins and springs so testing will be easy but I need to know what springs affect 2-3 accumulation and what springs affect 1-2 band apply so that I dont toast my band while trying to improve 2-3. Can I place spacers in there and how thick or where at? Can I use stiffer or lighter springs and which ones need to go stiffer or lighter? I dont mind a side effect of a better 1-2 in the prosses of getting a better 2-3 as long as it doent burn a band. THANX SO MUCH

 

[HOTTOGO]

Do just as diagram states, thus elimanating 3rd accumulator. If your second piston has a bleed hole in it, plug it. You can use a shim between 2nd & 3rd piston and this will tighten band clearance (which only helps 1-2), as long as 1st gear dosen't drag and you don't have 2nd gear starts it shouldn't be to tight.

 

[85 Riviera]

What will pluging the bleed hole on seconds piston do? I have lots of servos laying around with different size apply pins from 1 ring around the pin to 3 rings, would it be better to just use a longer apply pin or use the same one and shim it out further? ThanX for the info by the way!

 

[HOTTOGO]

It bleeds the 3rd accum. piston, but if you remove the seal it will allow the 2nd piston to bleed when trying to apply. Longer pin or shim either way works, but it's a guessing game if you have no way to gauge it. On a 2004r if you can still turn output shaft you should be alright.

 

[85 Riviera]

Ohh Now it all makes sence too me I got it now. thanx you answered all my questions now I am going to get to work. Thanx once again I'l let you know how it turns out. Oh one more thin you said on a 200-4R that you can turn the output shaft to see if the band is grabbing from a servo being adjusted too tight, so on my FWD rivi I could just lift the front wheels and have a buddy help me turn the other wheel and if they turn tight or dont turn at all then I can assume I adjusted the servo too tight. Does this sound right? Thanx!

 

[85 Riviera]

I got just one more question. If I remove the 3rd accumulator spring then it will be a must to shim the apply pin further out to make up for the pressure that the 3rd accumulator spring provided, am I correct? And were is the best place to shim the apply pin, I was thinkin between the 3rd accumulator piston and the apply pin were the spring used to be, is this correct? Thanx again!Pic of Servo

 

[HOTTOGO]

Save yourself the trouble...

http://www.2004rperformancecenter.com/mcartfree/product.asp?intProdID=24

 

[85 Riviera]

Well I dont want to buy anything because I spent enough on the rebuild alone. I was just wondering about how much should I shim the apply pin as a starting point if I discard the 3rd accumulator spring?

 

[HOTTOGO]

You need to take a measurement of exposed pin before and add what you lose by removing. Everyone is differ as there are many differ springs hieghts ans stiffnesses. If you remove only the spring, shim above piston, if you remove spring, c-clip, spring retainer and piston, just replace all with equal amount.

 

[85 Riviera]

All right cool Thanx for the help! I owe you one!

 

[85 Riviera]

All right!!! HOTTOGO!!! it worked. I took out the 3rd accumutator spring and piston ring as well as blocked the bleed hole with some JB weld. I also shimmed the apply pen to make up for the missing spring and I gave it another .030 more just to tighen things up alittle and it worked great. Now I got a more noticable stronger grab on second gear and a strong kick going into 3rd, Just what I needed, I dont like it so stiff that I break traction because this car is a FWD and it would eat right through tires at that point but I like my shifts firm enough to be positive and push the car with force into the next gear and now I got that for all 3 shifts. Thanks for your time See Ya

 

[HOTTOGO]

Great! Glad to hear it....

The only thing I would ? is the JB Weld thing, hopefully it won't become a prob for your sake but putting anything like that in a trannie not the best idea, I guess I should have told you to drill and tap it then loc-tite a setscrew in it. Maybe if ya have it out again think about it.

 

[85 Riviera]

yeah I will do that in a few day but at least I did a good job at the JB weld job and I gave it a full 24 hours dry time so it should last till sat. when I can get down n dirty again