Rev per miles for PP1

[GT_MTL]

Hello !

I replaced the OEM 18 inches wheel with OEM forged silver PP1 in 19inches.
Even if with the new tires/wheel setup there is a minimal circumference change I wonder if a PP1 owner could be kind enough to check using ForScan or Ford Procal tool the number of Rev Per Miles setup in the ECM so I could update mine.

I already did the computation but even with the original wheel setup I didn't get the exact same result than the one read through ProCal... So I'd prefer to stick to what Ford did for PP1.

Thanks !

Sponsored

 

[StangTime]

The more important info is what your rear tire size was and is now. Not the wheel size. So what tires did you put on those 19" wheels?

If you went with the standard PP1 rear tire size, that would be 275/40R19. The setting for circumference in Forscan for that size should be 2178mm. Note that it is not 2207mm as tire calculators would indicate. That is the circumference without vehicle weight. When the vehicle is sitting on the tires, they are effectively compressed about 8-10mm closer to the ground. Ford uses this adjusted circumference in the PCM. That is why a 2207mm should be programmed as 2178mm.

For Revs/mile. What does the Procal tell you and what was your OEM tire size before the change?

I have both a Procal and Forscan, but can't open my doors to get inside the car at the moment to tell you. Too much stuff in the garage.

 

[GT_MTL]

The more important info is what your rear tire size was and is now. Not the wheel size. So what tires did you put on those 19" wheels?

If you went with the standard PP1 rear tire size, that would be 275/40R19. The setting for circumference in Forscan for that size should be 2178mm. Note that it is not 2207mm as tire calculators would indicate. That is the circumference without vehicle weight. When the vehicle is sitting on the tires, they are effectively compressed about 8-10mm closer to the ground. Ford uses this adjusted circumference in the PCM. That is why a 2207mm should be programmed as 2178mm.

For Revs/mile. What does the Procal tell you and what was your OEM tire size before the change?

I have both a Procal and Forscan, but can't open my doors to get inside the car at the moment to tell you. Too much stuff in the garage.

Thanks !

Didn't mentioned it but yes, I have the PP1 OEM front+rear tire size.
Original OEM mount is 235/55-18 so therotically 718 rev per miles for 723 stored in PCM.
PP1 mount is (rear, where the sensor is) 275/40-19 which is theoritically 728 rev per mille. My guess is then I should put 733 to have the same ratio.

But I'd rather have the real value from you guys :-)

 

[StangTime]

My guess is it's going to be close to 739.
Let me see if I can get my Procal hooked up tonight to get an OEM PP1 reading for you. I need to change my tire size too. I changed to 325/30R19 in the back.

 

[StangTime]

Reading of OEM PP1 revs per mile. I was 1 rev off with my guesstimate.

 

[GT_MTL]

Reading of OEM PP1 revs per mile. I was 1 rev off with my guesstimate.

You won

Thank you very much!

 

[ice445]

Stock value for the 18's is 764 in case you go back or use them for a winter set or something

 

[GT_MTL]

Stock value for the 18's is 764 in case you go back or use them for a winter set or something

This is when I noticed that despite the fact that the PP1 19'' setup has a lower theoritical diameter than the OEM 18'' , the revs per mile is lower. Maybe because the tire is less deformed in real life ?? I guess some folks at Ford did the test for real :-)

 

[Zathras]

Hey GT_MTL, I have a question.... it looks like you have the A10 transmission. When you put these new, staggered wheels on, did you notice any problems or differences in how the transmission operates, such as shift points? (Or, with ABS & traction control?) I'm asking about how the car drove with the new wheels before the revs per mile was adjusted in the computer.

I don't have forscan or a laptop so I'm wondering what will happen if I upgrade the stock 18" wheels/tires but don't adjust the computer. I don't mind the speedo being a little off, but if there are other effects I guess I'd need to make the adjustment.

 

[GT_MTL]

Hey GT_MTL, I have a question.... it looks like you have the A10 transmission. When you put these new, staggered wheels on, did you notice any problems or differences in how the transmission operates, such as shift points? (Or, with ABS & traction control?) I'm asking about how the car drove with the new wheels before the revs per mile was adjusted in the computer.

I don't have forscan or a laptop so I'm wondering what will happen if I upgrade the stock 18" wheels/tires but don't adjust the computer. I don't mind the speedo being a little off, but if there are other effects I guess I'd need to make the adjustment.

Didn't notice anything so far but honestly I didn't drive it enough with the new wheels (I've got them just before winter).
I was wondering as well if it could influence the trans. I might reset the auto-learn...

Anyways, this will wait for that @#$%& track handling kit to come over and to install .

I'll keep you posted !

Sponsored