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MPH/Redline info needed

Strokerswild

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Time for a trip to Mexico. ;)
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Grintch

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Rear tire size for the PP is 275/40/19 which is 27.7" diameter. 7,000rpm redline.

  1. 3.66 = 42mph
  2. 2.43 = 64mph
  3. 1.69 = 91mph
  4. 1.32 = 117mph
  5. 1.00 = 154mph
  6. 0.65 = overdrive = 238mph
http://www.f-body.org/gears/

But the tire compresses, and slips, just a bit. So those numbers are slightly high.

I have:
1st - 41
2nd - 62
3rd - 89
4th - 114
5th - 151
6th - 232 (NOT)

Car & Drivers published numbers were just slightly lower, with the upper gears being a mph or 2 less (5th - 149 mph IIRC).
 

GT Pony

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But the tire compresses, and slips, just a bit. So those numbers are slightly high.

I have:
1st - 41
2nd - 62
3rd - 89
4th - 114
5th - 151
6th - 232 (NOT)

Car & Drivers published numbers were just slightly lower, with the upper gears being a mph or 2 less (5th - 149 mph IIRC).
Mine are even lower in Post #10. The numbers I came up with used the actual measured rolling circumference of the 19" tires on my GT. Yes, the rolling radius is about 2.5% less than the unloaded tires radius, and it certainly does have an effect as you mentioned above.

Also, I checked my speedometer against a Garmin GPS, and they both read within 1 MPH all the way up to 100 MPH.
 

Grintch

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But you are using the wrong redline/fuel cut. It's 7000 rpm not 6850.
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