PewterZ28

iTrader: (1)

I made the changes correctly in LS1Edit. I put in 4.1 as the gear and 26.4 as the tire diameter. I got the tire diameter off of Hoosier’s website. However, my speedometer is off by about 7 or 8 mph. Example, when I’m going 67 according to my speedometer, I am actually going about 74 or 75 according to my wife’s car and the speed check trailers.

Anyone else have this problem?

01350ss

iTrader: (18)

measure the tire yourself and double check your work.

Cal

iTrader: (1)

Yep, I've had that problem with several versions of edit. The problem has been improved on in the later versions, but it's still there. I adjust mine experimentally using mile markers on the freeway to fine tune it.

PewterZ28

iTrader: (1)

Well, I'll measure the circumference and then compute the diameter I guess. What psi should I put the tires at when measuring the circumference and should I measure with the tires on or off the car?

JimMueller

iTrader: (9)

At which speed ranges are we talking about? I think mine is off too, but I was under the impression that the tire diameter increased as speed increased. So that would mean you are traveling faster than the VSS reports, right?

It's cool to see the speed trailer numbers flashing when I take that 35mph S-curve