Tuner problems?

[TNT]

I just changed to 3:73 gears and purchased the Granatelli Diablo Sport tuner to calibrate my speedo. I changed the gear ratio but it still reads between 10 and 20 MPH off (to fast). The tuner also advanced my timing to much and causes it to knock/ping like crazy. I reduced the timing the full 10% that the tuner allows but it still pings and the knock sensor starts retarding the timing as soon as I step on it.

Anyone know why the calibration is off on the speedometer? Any ideas on stopping the pinging on crap California 91 octane.

[ninobrn99]

do you have all the updates for the diablo? may want to do that if you havent already, reflash to stock and try it again.

[mrr23]

http://runninwiththedevil.com/faq.htm that will explain how to correct the speedo. one day they'll actually fix it right.

[TNT]

Thanks for the info. The guys at Diablo Sport were very helpful and they did have me trick the computer by using the small tire size. They were also able to reset the tuner after adding the tune to allow me to take out an additional 5% on the timing to correct for the problem created by my factory settings and the 91 octane Cali gas. That trick is pretty cool because it allows you to take out additional timing (15% in my case) but if you had already raised the trans line pressure and shift speed it appears you can do it agian for higher pressure and quicker shift speeds.

This is basically how I did it. I put the Diablo Sport tune in the car and made all of the optional adjustments that I wanted like raising the trans line preasure and eliminating 10% of the timing to reduce the Knock sensor retard problem. Then I uploaded the tune information to my PC and saved the file as LS1 and the date. Then I put the tuner back in the car and reset the parameters on the tuner (I think I had to do this step twice to make sure the tuner cleared properly). Once you have reset the tuner parameters you downloaded the saved pc information back to the tuner and tune the car again. This basically tells the car that the tune is the innitial tune and then you can add or subtract additional timing or any of the other parameter that you originally adjusted. It seems that the Diablo Sport Tuner can go quite a bit further than the packaging would suggest but I haven't had time to mess with anything beyond the timing and tire size yet.

FYI the Diablo guys mentioned that this proceedure may very by version of the software on the device. I'm using the newest version 1.03 and they walked me through the entire process to eliminate the knock sensor problem that was pulling 3+ degrees of timing starting at about 1/2 throttle.