Shift points?
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There is a built-in RPM limiter (fuel cut-off) in the ECM. My '92 'vert with the A4 (2.73 gears) would cut out at just over 5800 RPM. The tranny would shift at WOT just before that, but holding the trans in gear with the shifter would still not change the fuel cut-off point.
So I think the A4 shift points would be the same RPM (or very close) regardless of what gears were in the diff. The only gears available were 2.59 for the standard gear in the 'vert, 2.73 as the "performance" axle ration in the 'vert and 3.07 for coupes.
So I think the A4 shift points would be the same RPM (or very close) regardless of what gears were in the diff. The only gears available were 2.59 for the standard gear in the 'vert, 2.73 as the "performance" axle ration in the 'vert and 3.07 for coupes.
Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
Unlike the 92 700r4 the 95s 4l60e shift points are controlled by the computer and are mph dependent.
Like c4Cruiser I figured the shift point were rpm related. However after my gear swap I set the tune for 3.45 on the speedometer set up and went for a high speed run and hit the rev limiter before the WOT shift would occur. So what I did for my gear swap " this was when my engine was stock," was to take 2.59/3.45 (2.59 was my original gear set, 3.45 was in the D44 I installed ) the resulting number was .75 so I multiplied the shift tables by .75 and ended up in the ball park and after a few tweaks I was happy with my shifting. I used tuner cat and a AKMS cable.
Good luck on the shift tables they were easier to adjust than I thought they'd be . Now my WOT shift points are at 6800 rpm and life is good.
Mike
Like c4Cruiser I figured the shift point were rpm related. However after my gear swap I set the tune for 3.45 on the speedometer set up and went for a high speed run and hit the rev limiter before the WOT shift would occur. So what I did for my gear swap " this was when my engine was stock," was to take 2.59/3.45 (2.59 was my original gear set, 3.45 was in the D44 I installed ) the resulting number was .75 so I multiplied the shift tables by .75 and ended up in the ball park and after a few tweaks I was happy with my shifting. I used tuner cat and a AKMS cable.
Good luck on the shift tables they were easier to adjust than I thought they'd be . Now my WOT shift points are at 6800 rpm and life is good.
Mike
Thread Starter
Heel & Toe
Joined: Apr 2009
Posts: 16
Likes: 0
Guess I sound have worded better. with 2.59Mine shifts out of first at 59MPH WOT will kick down back into first at 36MPH & 99Mph WOT & still kick down at 82MPH for second. I was wondering where they shift with the 3.07?
Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
I never messed with a 3.08 (didn't seem worth the effort for a LT1 car.
Since no one with a 3.08 posted, I'll give you the ballpark answer Current gear ratio/New gear ratio X current shift mph= new shift mph 2.59/3.08 X 59= 49. So change the shift to 49 mph.......all the other shift points can be calculated the same way. (now using a rpm figure and a gear calculator did not work for me since the torque converter slip/flare whatever causes the rpm to be higher than the gear calculator predicts.
In summary you can change the shift tables by a multiplier or manually tweak each cell.
Good luck.
Racer
Joined: Oct 2007
Posts: 478
Likes: 1
"Now my WOT shift points are at 6800 rpm and life is good."
Is this the number programed into the ECM or is the actual shift command a little lower at say 6600rpm? I'm getting ready to do mine and was just looking for guidance.
Is this the number programed into the ECM or is the actual shift command a little lower at say 6600rpm? I'm getting ready to do mine and was just looking for guidance.
Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
Originally Posted by aboatguy
"
Like c4Cruiser I figured the shift point were rpm related. However after my gear swap I set the tune for 3.45 on the speedometer set up and went for a high speed run and hit the rev limiter before the WOT shift would occur. So what I did for my gear swap " this was when my engine was stock," was to take 2.59/3.45 (2.59 was my original gear set, 3.45 was in the D44 I installed ) the resulting number was .75 so I multiplied the shift tables by .75 and ended up in the ball park and after a few tweaks I was happy with my shifting. I used tuner cat and a AKMS cable.
Like c4Cruiser I figured the shift point were rpm related. However after my gear swap I set the tune for 3.45 on the speedometer set up and went for a high speed run and hit the rev limiter before the WOT shift would occur. So what I did for my gear swap " this was when my engine was stock," was to take 2.59/3.45 (2.59 was my original gear set, 3.45 was in the D44 I installed ) the resulting number was .75 so I multiplied the shift tables by .75 and ended up in the ball park and after a few tweaks I was happy with my shifting. I used tuner cat and a AKMS cable.
So I started lower and tweaked it until it was where I felt comfortable.
Now that was with stock engine and just gear swap.. For my later builds I went with Ed Wright for TUNING and he set the shift points.
rpm reading is limited to 6375 by the GM datastream hence the use of rpm 13 which will display values higher than 6375. (its also more a more precise/accurate reading)
Last edited by aboatguy; May 14, 2009 at 09:24 PM. Reason: Not a no load dyno reading but on a drive home from work.
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Safety Car
Joined: Jul 2008
Posts: 3,966
Likes: 4
From: Made In America
St. Jude Donor '10-'11
There is a built-in RPM limiter (fuel cut-off) in the ECM. My '92 'vert with the A4 (2.73 gears) would cut out at just over 5800 RPM. The tranny would shift at WOT just before that, but holding the trans in gear with the shifter would still not change the fuel cut-off point.
So I think the A4 shift points would be the same RPM (or very close) regardless of what gears were in the diff. The only gears available were 2.59 for the standard gear in the 'vert, 2.73 as the "performance" axle ration in the 'vert and 3.07 for coupes.
So I think the A4 shift points would be the same RPM (or very close) regardless of what gears were in the diff. The only gears available were 2.59 for the standard gear in the 'vert, 2.73 as the "performance" axle ration in the 'vert and 3.07 for coupes.
Thread Starter
Heel & Toe
Joined: Apr 2009
Posts: 16
Likes: 0
I did get the 3.07. All the other tHings I am doing to the car. I am just sending the PCM to PCMFORLESS. There is only one guy there that seems to understand my setup. I guess I better talk with ED First. he seems to be the man.
