4L60E Issue - 1-2 Shift @ WOT
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4L60E Issue - 1-2 Shift @ WOT
I just put an FTI 3600 torque converter in my car and after transferring shift tables from a friend's car, we're having some issues.
We have the limiter set beyond the shift points, but it's still smacking the limiter on the 1-2 shift for almost a full second before shifting at WOT. I know it isn't spinning so obviously it isn't that.
I was told that all of the troublesome codes have been removed so I'm guessing that isn't the issue.
We checked the transmission fluid and it's full and a good color.
I can't think of what else it would be but I'm sure you guys know much better than I do. I did some searching and people were blaming issues like mine on codes that weren't removed but all of mine were cleared and disabled.
Any help is greatly appreciated
We have the limiter set beyond the shift points, but it's still smacking the limiter on the 1-2 shift for almost a full second before shifting at WOT. I know it isn't spinning so obviously it isn't that.
I was told that all of the troublesome codes have been removed so I'm guessing that isn't the issue.
We checked the transmission fluid and it's full and a good color.
I can't think of what else it would be but I'm sure you guys know much better than I do. I did some searching and people were blaming issues like mine on codes that weren't removed but all of mine were cleared and disabled.
Any help is greatly appreciated
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#4
did you figure out your problem yet? It sounds like I have the same problem...I went to the track today, first time out with my 3600 circle d in my lt1. It launched great but bounced off the rev limiter a couple times from 1st to 2nd...I was thinking I need to change my tune to shift a bit earlier.
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did you figure out your problem yet? It sounds like I have the same problem...I went to the track today, first time out with my 3600 circle d in my lt1. It launched great but bounced off the rev limiter a couple times from 1st to 2nd...I was thinking I need to change my tune to shift a bit earlier.
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A whole second or two, that's way too long. You should
look at log files and key on the trans current gear transition
(signal of intent) and the point where RPM hauls down
(signal of action). If that's really a second I think the trans
is messed up. Or pressure starved. But pressure profiles
should have changed none across a converter swap. Log
force motor current or PCS duty too. Some tune files have
stupid **** in the force motor table and pull all pressure at
WOT, prevented only by a max-line% limit entry elsewhere.
Some body leaves the former while another changed the
latter, and you put two wrongs together by a blind partial
copy, you could get some bad action.
Of course tenths may seem like seconds while the motor
is going whap-whap-whap-whap. There's that.
look at log files and key on the trans current gear transition
(signal of intent) and the point where RPM hauls down
(signal of action). If that's really a second I think the trans
is messed up. Or pressure starved. But pressure profiles
should have changed none across a converter swap. Log
force motor current or PCS duty too. Some tune files have
stupid **** in the force motor table and pull all pressure at
WOT, prevented only by a max-line% limit entry elsewhere.
Some body leaves the former while another changed the
latter, and you put two wrongs together by a blind partial
copy, you could get some bad action.
Of course tenths may seem like seconds while the motor
is going whap-whap-whap-whap. There's that.
#7
I had a mail order tune done a couple years ago when the car was basically stock, it shifted well and hard into 2nd. It was a tease at the track because I had a great 60 foot after the converter/gear combo, but just bounced off the rev limiter so the 1/4 looked terrible.
Iam hoping that its just the tune that is needed for me
Iam hoping that its just the tune that is needed for me
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#8
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I would bet $$$ that both issues are due to the tune. The pcm needs to satisfy both mph and rpm set points before the shift is commanded. It is common to over shoot the target rpm with an aftermarket stall converter and tag the limiter unless the limiter is set up out of the way especially when running the stock 4L60E.
If you have tuning capabilities, drop the WOT mph set point 5-8 mph as well as the part throttle tables in the 80-100% tps area. Also make sure the rev limiter (all tables, I think there are 4) is 400 rpm or more than the commanded shift point rpm.
If your tire size calulations (tire size and gears) are correct in the speedometer tables for your particular car then it should shift when commanded. G/L
If you have tuning capabilities, drop the WOT mph set point 5-8 mph as well as the part throttle tables in the 80-100% tps area. Also make sure the rev limiter (all tables, I think there are 4) is 400 rpm or more than the commanded shift point rpm.
If your tire size calulations (tire size and gears) are correct in the speedometer tables for your particular car then it should shift when commanded. G/L