Need to soften 1-2 shift!

RED LS1

SENIOR MEMBER
Joined
Dec 31, 2001
I had this trans built. I cant say with certainty what all was done to it. The 1-2 shift is crazy. It will hit the whole car hard even at a 20mph traffic roll. Every shift is violent. There not positive gear changes as much as there sledge hammer to the dashes.

Here is what I do know. the 1-2 accumulator was blocked. I was warned that it's going to do this but I thought the converter stall would absorb it. It's not. I didn't use any particular sep plate or shift kit but we played around with different spring combinations and such. 2-3 feels 100% dead on and everything else is cool. 1-2 shift feels great under WOT and there's no issue there. It's just way to aggressive at normal cruising.

I have a Sonnax Blue super Servo and I was told that I can pull the servo out and possibly make a change that will correct this. Maybe add shims, washers machine pin etc....?

What can I do?
 
there is an accumulator, feed orifice, and checkball that come into play with the 1-2.

You said the accumulator is blocked, what size is the feed hole drilled to and is the 1-2 checkball installed or not?

Are you talking about a shift in manual low or 2, or in D or OD?

What converter are you using?

Bob
 
Got a stock servo kicking around my Sonnax super servo hits pretty hard at WOT at the track with traction, fine on the street cause its usually hazing the tires going into second :p part throttle mine's good.
Did you install the stock cushion spring on the Super Servo?
 
there is an accumulator, feed orifice, and checkball that come into play with the 1-2.

You said the accumulator is blocked, what size is the feed hole drilled to and is the 1-2 checkball installed or not?

Are you talking about a shift in manual low or 2, or in D or OD?

What converter are you using?

Bob

I'm pretty sure we hammered a check ball into the accumulator passage to block it.

The car is always in drive. I havn't really messed with it in low (1) or 2nd. I just always leave it in drive.

The converter is a 9.5 inch 3200 stall. IT goes 2800 on the foot brake at zero boost and 3200 at 1-2 psi and maybe 3300-3400 holding 4-5 psi back.
 
I just blocked the 1-2 accumulator in my LS-1/200R4 Maverick due to a leaking piston, never saw any change at all...
 
Got a stock servo kicking around my Sonnax super servo hits pretty hard at WOT at the track with traction, fine on the street cause its usually hazing the tires going into second :p part throttle mine's good.
Did you install the stock cushion spring on the Super Servo?

I realize that most hard shifts attack the tires and chirp them or spin. This one is giving all the bang at the transmission which is resulting in a shock through the entire car.

I'm trying to jog my memory about the stock cushion spring in the servo. I know we discussed it but I can't recall. I was more of a bystandard while this was being built. We may have used a different spring I just can't remember for sure. The person who built it said we could soften it up by just going back into the servo and making a change. I just cant remember what he said. If I can find out I may be able to do it myself. Thats were I'm going with all this.
 
I had this trans built. I cant say with certainty what all was done to it. The 1-2 shift is crazy. It will hit the whole car hard even at a 20mph traffic roll. Every shift is violent. There not positive gear changes as much as there sledge hammer to the dashes.

Here is what I do know. the 1-2 accumulator was blocked. I was warned that it's going to do this but I thought the converter stall would absorb it. It's not. I didn't use any particular sep plate or shift kit but we played around with different spring combinations and such. 2-3 feels 100% dead on and everything else is cool. 1-2 shift feels great under WOT and there's no issue there. It's just way to aggressive at normal cruising.

I have a Sonnax Blue super Servo and I was told that I can pull the servo out and possibly make a change that will correct this. Maybe add shims, washers machine pin etc....?

What can I do?
 
HAVE YOU FIXED THE PROBLEM? IS SO HOW ? i HAVE THE EXACT SAME ISSUE ,FULL THROTTLE ITS OK , ANYTHING ELSE I CRINGE ! JIMMAG
 
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