markboris
Well-Known Member
- First Name
- Mark
- Joined
- Nov 13, 2019
- Threads
- 44
- Messages
- 5,758
- Reaction score
- 16,466
- Location
- Sonora, CA
- Vehicles
- Currently: '20 Shelby GT500 FPB '24 Mach-E GTP GGM
- Occupation
- Retired
A few comments on this....Did you change your speedo in ForScan? Looks like the tire size makes a big enough difference to warrant it. I am possibly taking my Mach e south of the boarder and have been looking at the Rally Wheels with the factory size 235/55-19 tires. I have not seen a post where that size was used most go wider. Traditionally Rally vehicles use a narrower tires.
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The speedo adjustment in FORScan is very minor as in you can only change up or down one tire size.
Typically the speedo on Mach-E's from the factory shows you going 1 mph faster than you actually are so changing to taller tires will actually get you more in line with the correct speed. I am currently running tires right now that are 29.7" tall (275/40R21) and the speedo reads a little less than 1 mph slower than I am actually going.
I know a few people running 29.7" tall tires up front (245/45R19) and 30" in the rear (255/55R19) which has been working out very well.
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