2-3 shift Flare

[SloGN]

Hey guys

i seem to not be able to get rid of this damn 2-3 shift flare i have, i have went from a duel feed back to a single feed and with the single feed it had got better

But it seems as if the second gear/band is releasing before the 3rd gear clutch pack can be applied... almost like it goes to neutral for a split second .... the start of the shift is 5550 rpm and then hits 6200 then back to 5400......

The shift takes about 3 tenths to happen before with the duel feed was about 6-7 tenths.

Also when it was dual feed it was mushrooming the clutchs and steels ....I added a second ring into the piston to try and even out the pressure apply on the steels and clutchs.....
that didn't really help .. so i went back to a single feed and now i'm almost there.


Thanks for any help guys

 

[TexasT]

How much clearance do you have in the direct clutches? What 2nd gear servo are you using? Clearance on it?

 

[SloGN]

How much clearance do you have in the direct clutches? What 2nd gear servo are you using? Clearance on it?

The direct clutches are set around .030...the servo i'm using is the large purple one.

 

[jpwalt1987]

What procedure did you use to dual feed the direct clutches?

 

[SloGN]

What procedure did you use to dual feed the direct clutches?

remove the middle center support seal ring...then remove the middle seal in the piston apply and then swap out the bolt on the center support to one thats blocked off with a check ball..

 

[INEEDAGN]

What's the size of the 3rd accumulator orifice in the plate? If you can't measure it, at least tell us what plate is in it/history of it

 

[SloGN]

What's the size of the 3rd accumulator orifice in the plate? If you can't measure it, at least tell us what plate is in it/history of it

I think its .200 you talking about the 55d check ball hole that gets a plug then you drill out the plate.......

 

[INEEDAGN]

If it's .200.....you found your problem....

I'll get a pic of the hole in question when I get to work to make sure we're on the same page. It should be .125 with what I presume to be a sonnax servo if it's purple.

 

[INEEDAGN]

This hole...will never work at .200...

 

[SloGN]

No that's not the hole I m thinking about ....I will look on my notes to what it may be

 

[SS/GN]

How much clearance on the band??

 

[TexasT]

image hosting

Maybe this will help get us to where your plate holes are. I lost my good plate pic(phone bricked last week).

If you drilled any holes in the plate to .200 I would concur that is way too big. I was told .125 was pretty big. I went .093 on several of the holes.
.030 is pretty tight on the direct clutches but if you aren't burning them more power to that.
What about the accumulators? Blocked, spaced out, stiffer springs?
Any other vb mods? Line bias valve? Accumulator valve?
Trans line pressure, tv at rest, full tv?

 

[Steve V]

On the servo it may be Bruce's as RC did those for a number of builders back in the day. I have Bruce's in one of mine and it is purple.

This maybe a stupid question, but I am sure you guys have gone over that at the Buick Mecca? Maybe give Dave Husek a call he's a smart guy as well.

 

[jpwalt1987]

Dave Husek has read this thread. Talked to him today. Give him a call, he has a few different ideas about doing a dual feed direct clutch setup. .030 on the directs should be fine. You may need an aluminum apply ring so you have a wider contact surface instead of the thin ring to avoid mushrooming the steels and clutches.

 

[SloGN]

If it's .200.....you found your problem....

I'll get a pic of the hole in question when I get to work to make sure we're on the same page. It should be .125 with what I presume to be a sonnax servo if it's purple.

No i'm wrong its 130/132 on the hole size ..... The servo is one of bruce toele units from PTS extreme...

 

[SloGN]

On the servo it may be Bruce's as RC did those for a number of builders back in the day. I have Bruce's in one of mine and it is purple.

This maybe a stupid question, but I am sure you guys have gone over that at the Buick Mecca? Maybe give Dave Husek a call he's a smart guy as well.

Yes Steve..... Its been down at the turbo buick mecca thats where i built it at !!!! i'm just trying to Fine tune it now....It seems to be living even with this small problem .

I really appreciate all the input guys ...

 

[INEEDAGN]

Probably still a bit bigger than it needs to be and too big will cause a 2-3 flare. If you don't find anything elsewhere you might peen that a bit smaller and try it.