Does anyone have any thoughts about the consistency of shifting by time opposed to rpm?

For me it depends on the type of racing.

I shift on time (.09) while index racing to initially slow the car and prevent tire spin when the throttle stop goes off.

I shift on RPM (7500) while bracket racing.

In my case each require different rear shock settings.

I prefer time shifted...if the car spins early in a run shifting on RPM it will almost always be slow due to the rpm getting up quicker and hitting the shift earlier than a run it did not spin. If it spins on time early in the run, with regularity it corrects the run by shifting later and ****her down track.

Results may vary with different combinations as this is based off of experiences thru the years with our stuff...

I think both time and rpm can be made to work equally as well. Most will choose rpm.

When using time you have to allow for an rpm shift window as better or worse weather will produce a higher or lower rpm shift activation point if time value is always the same.

If using Grid you can program the Launch Delay (Gear Shift tab), to hold the gear indicator, and I believe it will also not allow an early shift (Shift Light Output) if spinning the tires in 1st gear.

My transmission shifts to hi gear with rpm (first programmed output), time (second programmed output) and over shift rpm (third programmed output manually activated) all running together and attached to shift solenoid.

During the run, one could manually control what output (rpm or time or higher rpm) shifts the transmission using the bump up/down button if desired.