speedometer ?

[98GreenC5]

I am a new user of HPTuner, just got it a couple of days ago.

I compared several of the Tuner edit frames with those of LS!edit and have found some small differences on values read out of the pcm,

The real strange one is the speedometer frame,
on LS!edit it shows current gear and tire size of 3.42 and 26.1,
on the Tuner frame the previous (cu rrent?) tire size is blank and the gear ratio shows a dim 15.98..

This makes me a little nervous would like some help /reassure ance about this,,,

Thanks.

[Keith@HPTuners]

Can you please send us your binary so we can look at it.

[98GreenC5]

Binary sent..............

Thanks for the reponse,

[Tim_Sloper]

Keith I am seeing odd behavior as well on my 98 F-body. LS1-edit shows

Gear 3.23
Tire 25.63
VSS (PPM) 52358
VSS (PPR) 10240

VCM Editor shows

Previous TH - blank
Previous GR - blank
Engine (PPM) 52358
Trans Scalar 4.0
Speed Input Pulses Per Mile 7812

You should receive a .zip (ls1_edit.zip) of the VCM .bin

Tim

[Keith@HPTuners]

98GreenC5, I checked your binary and it is ok.

If you make gear changes enter 3.42 and 26.1 as the previous (Saved) values and then enter the new values in the right side boxes to make the changes, then click save changes to commit.

The values below are what is calculated when you click save changes. They are the actual values the PCM uses to determine actual MPH for both the engine and transmission.

[98GreenC5]

Keith,

Don't you guys ever sleep?

I tried your suggestion to put old tire size (26.1)in previous and it entered ok.

If I try to enter anything in previous gear ratio , it is not allowed.
(no message just no entry- the grey 15.98 stays)

when I enter 26.1 /3.42 as new tire size/ gear ratio,
the values below change...

if I'm not changing anything why do these values change?

Something is not right with the 15.98 in the previous box.

I'm glad to know that the values are right in the VCM,,but
I'm glad I don't have to change tire size or gear ratio because
I would not have any faith that it would be right..

Richard

[Chris@HPTuners]

we are working to enhance this functionality in future releases.

For 98's the way to modify the values is to calulate the scaling factor by:

factor = (new gear/old gear) x (old tire/new tire)

note: increasing gear increases the factor, whereas increasing tire decreases the factor.

then multiply both the PPM (for cluster calibration) and Trans Scalar (for trans speed calibration) by this factor. Enter them manually.

although, i would bet that your Trans Scalar is not modified from what it was as stock.

[98GreenC5]

OK ,i looked at my stock file and the values are:
engineppm 15514
transscalar 4.000
speed inp/mi 7812
original 2.73 rear 275/40/18 tire.

my modified file:

engineppm 15852
transscalar 4.000
speedinp/mi 7812
3.42 gear 295/35/18 tire.

you are correct that scalar is same as stock
I'll be happy with what I have until the enhancements
in the future fix it so you don't have to be a math whiz
to change tire/gear in the program.

LS1 edit has these values in the tables for the 26.1/3.42
VSS 15852 pulses/mi
OSS 2990 pulses/rev

if this is any help.
.

looking forward to when everything works as expected...

thanks for your time and effort.................

Richard