i know he has the the tap shifter working because i have ridden in a truck with it. as for the tc lock up i know the turbo brake has a feature where it locks the converter at the start of second gear when the TH is on. works everytime in my truck.
TC Lock-Up Switch
- Thread starter bullfrogjohnson
- Start date
it depends on converter and power level , mine WOT locks around 50 mph ( from logging input vs output rpm ) wich would be middle of third . not shure what paramiters are suposed to be met before lock up is allowed ?
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its "supposed" to lock in second, but it never seems to. There is some table in the TCM that inhibits lockup if the converter slip rpm is over a certain value. Thats why you get some allisons that, under big power, you launch, 1st gear, 2nd gear, etc... and because of the power, you're blowing through the converter, and the converter doesnt really start to couple (and bring the turbine vs. input speed difference down below X rpm) until ~55mph in third gear.
Ive been asking about this for 3 years, no one can explain it or help other than say "buy a co-pilot". There is no such thing as consistant converter lockup in the allison when you are running big power.
some TCM tunes help, and I know there are some guys who insist "mine always locks as soon as it shifts into second etc.." and then they send me their "magic bullet" TCM tune, I load it, and big surprise, mine still acts like an idiot.
its a little better with my refreshed 1057 thats not loosey-goosey but its still somewhat annoying.
ben
Ive been asking about this for 3 years, no one can explain it or help other than say "buy a co-pilot". There is no such thing as consistant converter lockup in the allison when you are running big power.
some TCM tunes help, and I know there are some guys who insist "mine always locks as soon as it shifts into second etc.." and then they send me their "magic bullet" TCM tune, I load it, and big surprise, mine still acts like an idiot.
its a little better with my refreshed 1057 thats not loosey-goosey but its still somewhat annoying.
ben
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its "supposed" to lock in second, but it never seems to. There is some table in the TCM that inhibits lockup if the converter slip rpm is over a certain value. Thats why you get some allisons that, under big power, you launch, 1st gear, 2nd gear, etc... and because of the power, you're blowing through the converter, and the converter doesnt really start to couple (and bring the turbine vs. input speed difference down below X rpm) until ~55mph in third gear.
Ive been asking about this for 3 years, no one can explain it or help other than say "buy a co-pilot". There is no such thing as consistant converter lockup in the allison when you are running big power.
some TCM tunes help, and I know there are some guys who insist "mine always locks as soon as it shifts into second etc.." and then they send me their "magic bullet" TCM tune, I load it, and big surprise, mine still acts like an idiot.
its a little better with my refreshed 1057 thats not loosey-goosey but its still somewhat annoying.
ben
Ben, this is exactly what mine is doing. I cant notice it that much on the pulling track but in the 1/4 mile I can really tell. Its making my 1/8 times suck.
YUP!!!!!!
thats why, back when I drag raced my truck, it would easilly trap 108mph in the 1/4 mile but never faster than a 12.9 ET. If my stupid converter locked when it was supposed to, 108mph SHOULD be a low 12.
ben
The reason I asked is that with my '05 and '07, lockup was inconsistent when using stock shift points...Raising them to 3600 cured that...It will lock everytime in 2nd gear T/H, but I'm not running "big power"...
i will have to try a few things .... might try and lower the WOT mph and see if it will let it lock earlier , it feels good on power still .... the tcc slip is 300 rpm @ 47 mph, 48mph its around 70 rpm slip and by 52mph its 0 . and i am still getting rpm drop between lower gears so even not locked it is coupling good .
Dang!,
I am glad I am not the only one. I was so frustrated because this last time at the track i was running 12.8, 13.0 @ 108 and could not do any better
i assume the 60ft's were in the apropriate rangeDang!,
I am glad I am not the only one. I was so frustrated because this last time at the track i was running 12.8, 13.0 @ 108 and could not do any better
?
i agree
I'd rather my truck run poorly than with run well with a copilot.
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