I went from the stock 24.6 to a 25.3 tire and when I changed it in HPT I lost my cruise control completely. What's the deal? I even reset the final drive to 3.05 where it was before because I noticed that when I changed to the 25.3, the final drive went to 1.00:1 for some reason. It's not good either because according to the traps at the end of the 1/4 when I'm doing 102 on the speedo in HPT, I'm actually crossing the traps at 109.
Last edited by dont_blink; 04-30-2008 at 11:36 PM.
RSG Offroad
Jeeps. Jeeps. And more Jeeps. Oh and Jeeps too.
Nobody? Nothing?
RSG Offroad
Jeeps. Jeeps. And more Jeeps. Oh and Jeeps too.
Come on.
RSG Offroad
Jeeps. Jeeps. And more Jeeps. Oh and Jeeps too.
I too have lost my cruise control? Anyone have any ideas?
Kane
So nobody else has had this issue and corrected it?
I've got some slightly larger tires coming too, anyone figure this out yet?
I did some testing and cruise control works up to 45mph then no longer works. So it seems there must be another adjustment that needs to be done if you change the tire size. I will continue to play with but if anyone has some ideas please let me know.
Kane
I am still testing but I am surprised no one has an answer. Chris or Jay???????
Man I am going out of town this weekend and was hoping to use the cruise control. Well I guess worst case I set the tire size back and just adjust my speed.
Kane
still no luck then eh
2005 Cobalt SS Supercharged
GM Stage 2
Injen CAI
Vibrant Header, DP, and GMPP Sport Exhaust
Hurst STS
Nope you can not tell me there is no solution. I am going to play with it some more today because I am taking another trip and I would like cruise.
What is everyone else doing? Just dealing with it?
Kane
Changed my tire size from factory tire size (29.6" I think) to 33" mudders (measured 32.5"). Typically not on the highway often but was able to test it a few times. Knock on wood...........I currently still have full use of my cruise control. Anything you want me to look at on my stock or current modified tune?
Steve
2007 GMC Canyon Z71-4x4 | 3.7 I5-Auto | 4" Skyjacker suspension lift | 3" Performance Accessories body lift | 33x11.5x17 tires (going 35x12.5x17) | 3.73 gears | 57 K&N | BPi VS | AMS EaAU 6081 | SSK MAF Adapter | NGK AFX w/ NTK WBO2 | AMSoil fluids
maybe this info from WopOnTour will help a bit :
The ratio is shown as 1:1 because of the placement of the Vehicle Speed Sensor (VSS)
In a FWD car it's typically AFTER the final drive reduction and therefore does not affect the Pulses Per Mile setting. On a RWD the sensor is mounted on the transmission BEFORE the final reduction so the the rear axle gear ratio must be taken into account,
AS far as the values used for the tire, you must measure the ROLLING circumference (using the chalk line method) and divide by pi and use that value as your diameter. (do not just measure the diameter with a tape measure)
Then mutiply THAT by 30 (the number of teeth on the 2004&05 Redline speed sensor reluctor aka Pules Per Rev in HPT) and enter THAT value as your new Pulses Per Mile.
For the Cobalt (or 2006-07Redline) the process is slightly different as you must use a Pulse Per Rev of 85 as the reluctor has 85 teeth.
HTH
Wop
my_bd 2004 Saturn Ion Redline - 2.0L Supercharged LSJ (P12) 13.1 @ 110
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