|
|
|
|
| Author |
|
|
Registered
Join Date: Aug 2012
Location: Philadelphia Area
Posts: 3,669
|
Speedo Accuracy/True Mileage
Both my '86 911 and my '83 928 wear the stock original wheels/tire size and both have optimistic speedometers. Both when showing around 70 mph are actually doing around 63 - 64 mph.
This seems common with Porsche from my experience. Doesn't this mean with an electronic speedo that my true overall miles on the cars are a percentage lower? If so, and the speedos made accurate, can the the miles be legally changed to a lower number?
__________________
Matt Mariani @the_r_institute Authorized Retailer FIKSE Wheels Mod Italian Wheels Maxilite classic wheels |
||
09-19-2012, 03:38 PM
|
|
|
Registered
|
I have a Hayabusa motorcycle which has a 7% optimistic speedometer...actually they all are. Oddly the odometers are extremely accurate as tested by many owners. Try checking yours against highway mile markers or use a GPS.
My 928's speedometer is probably the most accurate out of any of my vehicles. At 70 mph indicated I'm actually doing 71 according to my GPS. I'm running 265/30-19 on the rear which is almost identical to stock tire height.
__________________
George in Indiana 928 Weissach #153 Cayenne S |
||
|
09-19-2012, 06:03 PM
|
|
|
Kyle C
|
I think most speedometers (not just in Porsches) err on the side of optimism. Better than reading lower than actual speed!
__________________
1974 911 1978 928 5spd hillclimb special 1984 928S 5spd, 1986.5 928S auto 1983 944, 1984 944 track car 1995 Saab 900 S, 1997 Saab 900 Turbo, 1999 Saab 9-3 S |
||
|
09-20-2012, 06:17 PM
|
|
# 153
