06-29-2008, 08:58 AM | #11 |
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When I bought my tune I had to send ford the vin#, tire size I was currently running as well as the gear size. They processed the info. and sent it back for me to get installed.
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2007 SHELBY GT CSM073649 1992 Black on Black Vert lx 5.0 1985 Chevy c10 383 stroker 2000 Jeep Grand Cherokee 4.7 (daddy mobile) |
06-30-2008, 07:50 AM | #12 |
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Lee, the stock tire may have been 55, I can't remember for sure. They were only on the car for 1 day before they were changed.
89 Hoss, I had to give the same info for my tune also. It would be interesting to see if your car is off as well.
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Mean Little Man |
06-30-2008, 08:02 AM | #13 |
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Yeah, but he went from a 17 to an 18. If the tire is 1" shorter, then it should be about perfect then since that would make up the 1" difference in wheel size right?
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1989 Saleen SSC 1988 AL DPS SSP |
06-30-2008, 09:28 AM | #14 | |
Daddy x4 ...we're done
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Quote:
(((275/25.4)*.35)*2)+18 = 25.578" tall tire/wheel combo . . . which, as Lee already mentioned, is a lot shorter than the stock tire and therefore would register a faster speed.
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06-30-2008, 10:54 AM | #15 | |
Si vis pacem, para bellum
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Quote:
For some reason I couldn't wrap my mind around the concept that going from a 17 to an 18 would be smaller. But thinking how tall the stock tires are on the new ones, it's starting to click now.
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1989 Saleen SSC 1988 AL DPS SSP Last edited by NightHawk756; 06-30-2008 at 10:58 AM. |
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06-30-2008, 03:07 PM | #16 | |
3v's are slow
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Quote:
It (1.5" shorter tire) actually should have created a larger difference in his speedometer than what he is showing. I am ass'uming that either the FRPP tune is either wrong or is limited in what tire size values you can input and they just a size that was close to what he has on the car. Ray, 89 Hoss no longer has the car that he installed the FRPP tune in but I don't think he had any major speedo issues. He ran a 275/40/18 on his car
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy |
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06-30-2008, 03:08 PM | #17 | |
3v's are slow
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Quote:
Also, the guy with the Razors should be running a 255/35/20 if he is running the same size at all 4 corners
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy Last edited by QWKSNKE; 06-30-2008 at 03:13 PM. |
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06-30-2008, 04:24 PM | #18 | |
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Quote:
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2007 SHELBY GT CSM073649 1992 Black on Black Vert lx 5.0 1985 Chevy c10 383 stroker 2000 Jeep Grand Cherokee 4.7 (daddy mobile) |
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06-30-2008, 07:59 PM | #19 |
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Now the million dollar question: How to fix it without redoing the FRPP tune or changing wheel sizes?
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Mean Little Man |
06-30-2008, 08:10 PM | #20 |
3v's are slow
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you can't. either modifying the tune or tire replacement will be required
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy |
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