You've got something there.

I'm still confused as to how he thinks it'* off by 13mph. How can a speedo be set for kms unless it'* a Canadian car?

Like Technical Ted was saying the 30 kp = 18 mph.

The conersion is:

1KPH = 0.62137 MPH
1MPH = 1.609344 KPH

I'm not denying that. That'* what actually makes sense to me.

Some cars can switch between MPH & KPH. I guess the big question is can this be done in a 96 SE?

I cannot do it in my car (97 SSEi) to the spedometer on the dash or the HUD. I've looked and the manual does not metion a thing about it

Does your speedo have two sets of numbers?

It does, but not for the HUD

That'* what'* got me stumped. On a 96 SE it'* not possible. He'd have the normal speedo that has mph on top and km on the bottom. And I doubt he has a HUD. But if he did it would clearly say km or mph which would be impossible to confuse.

The new speedos have one set of numbers which switches between miles and kms.

He says his speedo is at 30mph, but he knows he really is doing 17mph. How would he even know his 'real' speed is 13mph slower? Anyone see what I mean? Something isn't right..or I'm just really off tonight.

Maybe the original poster can give us some more info. Do we all agree that changing to those tires wouldn't change the speedo by more than 10%?

Definitely. A 13mph difference is way too much. The 15" tires were 60 sidewall, and the 16" tires have a 50 sidewall. Almost seems like they would cancel each other out. I don't know what that is in inches, but I don't see how it can be that much larger.

I think we need more precise info. The diameter of both wheels w/ tires would be a start.