I'm curious for those who have data recorders. How long does it take for your trans to make the shift. I.E. from the time it hits the shift rpm to the time it actually shifts, (you see the rpm start to drop). Mine is .040 and I would like to know if that is a typical/reasonable number. My rpm stays at the shift rpm for that amount of time then starts to drop.

1.76 glide if that matters.

Mine is .32 from the time the shift solonoid to fire and for the rpm to drop. It is also .3 from highest rpm to lowest rpm. At .4 you are really good, but there are things that can be doen to speed the shift up. With that being said, sometimes, making them shift quicker, can cause it to upset the drive shaft on the shift.

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Originally posted by 329L:
Mine is .32 from the time the shift solonoid to fire and for the rpm to drop. It is also .3 from highest rpm to lowest rpm. At .4 you are really good, but there are things that can be doen to speed the shift up. With that being said, sometimes, making them shift quicker, can cause it to upset the drive shaft on the shift.

Thanks for the info. Not really looking to speed it up, more so just wondering where I am or should be on that time. Only has 388 runs on it and I have never had a single trans problem with any my friend has built for me.

We always want to be as good as possible and I have small run differences. I want to be as consistent as possible. Usually it's the track changes I believe that give me small consistency challenges but making sure things are good with the car is the things I can control.

I log the time from launch that shift initiates and maximum rpm after shift in a th400 using only second and third gear.

With th400 in second gear, the direct drum is stopped and shifting to third picks up the direct drum to spin same direction as the forward drum. This takes 0.190 to 0.200 and rpm increases from 90 to 100 rpm during this period.

PG shift extremely fast compared to a th400.

th400 shifting