1963 Fury tire size vs speedometer

[Stephen Taylor]

Currently on our 63 fury 4 door hardtop are firestone p225/70 R14 tires all (4) same size the spare in the trunk is a 195/75 R14 Gillett Golden Bear. with all that said checking the speedometer with GPS it is about 2-3 MPH off (slow) so car indicating 40 by GPS is actually 37-38. Nothing major just looking to put as correct of a tire as we can. Plan to stay with a radial as she will be on the road quite a bit.
Being a little slow for a teenagers car might not be a bad idea.

 

[toolmanmike]

A speedo gear change might get you closer but I would leave it.

 

[ruffcut]

Sounds like it could save you from a speeding ticket?

 

[Nate S]

I guess if you want to change tires you could change size as well. There are calculators online for that. I'd put on the tires you want (or match factory dia) and then change the speedo gear to get it right. It looks like these are being reproduced now (don't confuse with later more common gears). I have a 19 and a 17 kicking around if you need one. In my case I matched factory tire dia and the speedo read high by 10% and the odo high by 5%. I went from a 19 to a 21 tooth gear so now the speedo is right on and the odo runs 5% low.

 

[Darter6]

Going from a 225/70 to a 205/75 should correct the numbers.My 2 cents.
I just swapped from 215/75/15 to 205/75/15 same brand of tire and the 205's are 1'' shorter.