4l60e VSS vs RPM Shift question?
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4l60e VSS vs RPM Shift question?
Hey guys, I'm new to tuning electronically controlled transmissions for I have been running a Th400 mvb for two years now. Well I bought another car to DD and I am playing around with the tune a bit using my normal EFI Live. Car is a 02 A4 SS.
The car is upshifting just fine with the new set perimeters however i do not understand the correlation between VSS and RPM shift points. I was looking at a stock tune and I think the 1-2 is set at 6000 rpm but 60 mph. How does this work?
I will be changing shift points pretty regular until I find the optimum range so when I start to make the larger jumps how will I correlate the two to make it shift properly.
edit: I guess I'm kind of looking for a rule of thumb if one exist. EX. xx mph equals xx rpm or reverse to make the car shift.
Thanks in advance!
Andy
The car is upshifting just fine with the new set perimeters however i do not understand the correlation between VSS and RPM shift points. I was looking at a stock tune and I think the 1-2 is set at 6000 rpm but 60 mph. How does this work?
I will be changing shift points pretty regular until I find the optimum range so when I start to make the larger jumps how will I correlate the two to make it shift properly.
edit: I guess I'm kind of looking for a rule of thumb if one exist. EX. xx mph equals xx rpm or reverse to make the car shift.
Thanks in advance!
Andy
Last edited by Carter01; 04-07-2012 at 12:46 PM.
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For WOT the mph value must be met first, then the PCM looks at the rpm. I wouldn't raise the shift points with a stock cam and valve train, but if you choose to do so you should be able to just raise the rpm value. Adding an aftermarket TC changes everything where you have to drop the mph really low to force the PCM to shift based on rpm only.
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For WOT the mph value must be met first, then the PCM looks at the rpm. I wouldn't raise the shift points with a stock cam and valve train, but if you choose to do so you should be able to just raise the rpm value. Adding an aftermarket TC changes everything where you have to drop the mph really low to force the PCM to shift based on rpm only.