9000th01ss

iTrader: (10)

I have an '02 F-Body, I've ran it with HPTuners scanning and added the "trans shift mode" PID
I added this by accident. But I did notice during somewhat normal driving it indicated it was shifting off the MPH table at WOT.

My question is, what determines which table it shifts off of?
What would cause it to shift off the WOT table vs the MPH table?

SSpdDmon

iTrader: (10)

Throttle position. There's a setting that says, "consider the car to be in WOT mode once TP% is greater than xx.x%." That's how it distiguishes between PT and WOT.

Either way, RPM and MPH are both a trigger for any shift (WOT or PT). You need to meet the MPH and RPM requirements in order for an upshift to take place.

edcmat-l1

iTrader: (10)

They shift off the MPH primarily. The RPM is the backup. If you do not exceed the MPH and hit the RPM, it will shift off that table.

9000th01ss

iTrader: (10)

Alright, that makes perfect sense.
Thanks a lot guys.

9000th01ss

iTrader: (10)

I need to bring this back up.
So according to this quote I can set the MPH to 256 and it'll shift off the WOT shift RPM table?

Is there a time delay for how long it's been at WOT and when it starts shifting off the WOT table?

I'm asking because I recently logged two runs at the track, they consistantly shifted 1-2 off the MPH table and 2-3 off the RPM table.

I guess my plan is to program both tables so the actual RPM and MPH match each table. For example, if I want it to shift at 6300 rpm and the calculated mph is 83 at 6300 rpm, I'll put 83 in the mph table (and make sure the main fuel cutoff is higher)

Is this the way it's typically done? Or is there another way?

DaveX

I drop my wot MPH shift points a little and adjust it with RPM only.

edcmat-l1

iTrader: (10)

By the sound of it, your 2-3 shift MPH is too high. That's why it shifted off the RPM table.

9000th01ss

iTrader: (10)

It's not though. 2-3 is set at 76 mph (actual shift at 83 mph), and 1-2 is set at 40 mph (actual shift 41 mph).

1-2 and 2-3 is set at 6300 rpm.

I guess a log and a tune will help so I'll attach it.

PS, the reason I want to raise the shift rpm is because I picked up .2 shifting it manually at a higher rpm. I'd like for it to shift automatically.

98Camarod

iTrader: (43)

So if I'm reading this right, WOT shifts should have the speed set to the max and then it will shift off of the rpm table?

edcmat-l1

iTrader: (10)

It does look like it shifted off the RPM table, but if you look at the time from when it hit 76 mph, to when it SAYS it shifted, it was less than 1 second. It could very well be that it took it that long to happen. It actually increased another 150 rpm before the shift actually took place.

This is the reason on the higher HP cars that rev quicker, the shift tables need to be set lower than you want them to shift, because of the time delay. Not saying this is a higher HP car, it's just a good example.

DrkPhx

iTrader: (15)

I'm pretty sure it actually shifts based on rpm, however the mph value must be met first, then it will shift. I have all of the mph values in my shift points set way low and it shifts dead on. Keep in mind if you set them with street tires and switch tires (different height) at the track, this will affect the shift points as well.

9000th01ss

iTrader: (10)

Alright you guys, thanks for that info. Now I know what direction to go with it, I'll try a few changes and see what happens.

Dragman

I do this also but I have complained it not very consistent on shift RPMs run after run.

Sid447

This is correct.

It's better to have the speed parameters set either at 0 or stock factory settings and concentrate on getting the rpm settings how you want them allowing for the shift delay (150-250rpm approx).

Sid447

^^^^^^^^ ditto this.

rel3rd

iTrader: (43)

When I had my car professionally "tuned" a year and a half ago, the tuner had the WOT shifts set by MPH. For the car to shift at 6700-6800+, he had the WOT shift RPM set at 6200.

Since then I have purchased my own HPTuners setup and did what DrkPhx does. I set my WOT SHIFT MPH exactly 10 mph lower than what was datalogged on several different runs. The car shifts (according to datalogging) within 50-100 rpm's above whatever WOT SHIFT RPM I have it set at...everytime. That is with a stock, unmodified 4L60E in a 3755# car that runs 11.60's.

The way it previously shifted was very inconsistent and had revved as high as 6882 rpm's...or nearly 700 rpm's above what was programmed in originally, and was obviously not right.

edcmat-l1

iTrader: (10)

What you guys aren't considering is the time it actually takes it to shift, and how fast the RPMs are climbing.

I just tuned a car yesterday, had to set the RPM AND MPH table much lower to get the shift done by 6000. Had to set the RPM to 5700, and MPH to about 73 MPH I believe.

Even with the shift times set to zero (they are anyways in the perf table) the pressure jacked up, etc., it still can't get it done fast enough.

rel3rd

iTrader: (43)

All I can share is that I have several datalogs that tell me with my MPH settings set artificially low, my stock transmission shifts within 50-100 rpm's above my commanded WOT shift rpm, everytime. When MPH setting was up near actual shift MPH, I had the same issue you describe. Very inconsistent.

My transmission is stock...no shift kit, no special servo, no anything that it didn't have in it when new.

tording99Z28

iTrader: (3)

I changed my upshift mph table to 0's so that the upshift requirement is always met, then the PCM only uses the RPM table to shift off of. Like edcmat said though you have to command the shift earlier than you want it to happen so that it happens before you hit the limiter. Works like a charm.

tording99Z28

iTrader: (3)

This is incorrect. If you set the speed to max then the computer will not command the shift until that speed of 256 mph is met. It would need to be the other way, set all your upshift speeds to 0 so that anytime you are moving the speed requirement is met, then it will use strictly the rpm to command the shift.