Speedo Calculator issues...Help Please

[Blacky]

Hi Kenny,

I received your email, thanks.

My mistake, the image I posted was from a 2000 LS1, but I had upgraded the PCM to a 2002 operating system. So the limit you see in the image is from a later OS.

The "physical" PCM limit for the 2000 LS1 is 0 to 131,070 however, we have found that setting the speedo values to their absolute min (0) or max (131,070) values can cause the speedo calculations in the PCM to get a "divide by zero" error. To prevent that, we artificially limit the speedo settings in EFILive to 100..90% of maximum.

In the 2000 LS1 operating system 90% of 131,070 is 117,963. Unfortunately, it looks like that is not high enough to allow certain combinations of tires/diffs. In the next release, I will set the limits to 100..98% which will give the 2000 LS1 a range of: 100..128,448

Unfortunately there is no simple workaround for this problem right now.
The only option would be to upgrade the PCM's operating system to 2001/2002. But that is not trivial and the calibrations cannot be easily copied to the new OS.

An updated version of the software will be available in a day or two.
Please subscribe to this thread to receive notification when it is available.
http://forum.efilive.com/showthread.php?t=4442

Regards
Paul Blackmore
EFILive Limited

[KAZ MotorSports]

The wheels and tires are stock size on this car. So changing the gear ratio from 3.23 to 3.73 is that radical of a change to walk it out of it's limits? Bummer.

I will let my client know it will be a few days before we get things correct. He absolutely loves the way his car is now compared to his PCMforless tune was...but the speedo issue is a thorn in his side which I can fully agree with. The .tun file I sent you if for your eyes only and not to be published please.

I TRULY APPRECIATE YOUR HELP PAUL!!

I am eagerly awaiting the update.

Thank you for your help,
-Kenny

[Blacky]

The wheels and tires are stock size on this car. So changing the gear ratio from 3.23 to 3.73 is that radical of a change to walk it out of it's limits? Bummer.

No, it's not a radical change. The PCM can support your setup no problem - just as soon as I raise the upper limit.

We can cause our test PCMs to lock up if/when H0101 is set too high (or too low). The exact number varies between different PCMs, so we took a conservative approach and set the maximum for ALL PCMs to 90% of the actual maximum limit. Unfortunately the conservative approach was too conservative.

We figured it was better to have a PCM with a speedo that is (temporarily) wrong, than to have a dead PCM.

Regards
Paul

[Redline Motorsports]

Paul,

Chad and I saw this problem this weekend. We got around it but its in Chad's head!

Howard

[Black02SS]

:lol: I will get it all in an email and send it to Paul tomorrow.

[KAZ MotorSports]

No worries Paul. I hope you did not take my statement as a jab at the software. I absolutely enjoy the software and feel you guys have outdone yourselves in how effective the software is for tuning...especially compared to other software packages I have test driven.

Thanks again to you Howard for spending time with me on the phone today trying to get this straightened up. I look forward to meeting you in June for the EFI-Live class!

[KAZ MotorSports]

Thank you Paul! It worked perfectly.

-Kenny

[Blacky]

No worries Paul. I hope you did not take my statement as a jab at the software.

No offense taken We need (and actively encourage) people to report any and all problems. That's how 90% of them get fixed.

Regards
Paul

[Spdfrk1990]

How exactly does this work I have the stock tire size and speedo settings. I entered the tire size anyway to see if it changed and the diameter/cir/revs did but when I hit apply it changed H0104 from 805.1953 to 2687.8238??? Also H0101 from 47020 to 45693 that part seems normal tho. Should I just leave the stock setting alone or whats going on.
Using v7.4

[Blacky]

I presume you have a manual gearbox.
As the description for H0104 says:
For manual vehicles, it is not used and is often set incorrectly.
For automatic vehicles, it is used by the PCM to determine the transmission shift speeds.
805 is wrong, 2687 is correct. However, it doesn't matter if you have a manual trans, that value is ignored.

I should add another piece of text:
For manual vehicles, it is not used and is often set incorrectly (by the factory).
For automatic vehicles, it is used by the PCM to determine the transmission shift speeds.

Regards
Paul

How exactly does this work I have the stock tire size and speedo settings. I entered the tire size anyway to see if it changed and the diameter/cir/revs did but when I hit apply it changed H0104 from 805.1953 to 2687.8238??? Also H0101 from 47020 to 45693 that part seems normal tho. Should I just leave the stock setting alone or whats going on.
Using v7.4