I recently heard that the car can be tuned for new tire sizes other than stock in order to keep the speedometer working correctly. Where is this option in Ecuflash?

 

Interesting...

 

There isn't an option in ECUFlash yet, but I wouldn't be surprised if it was possible!

(considering Tephra has control of the tach)

 

Anyone know if the other tuning software like Cobb or Ecutek has it?

 

i bet the dealer could do it, but wow that would be awesome if cobb or ecu flash could add this feature

 

It would be nice to get some input from Tephra to see how hard it would be to implement something like this.

 

Most tire sizes you can run on the Evo don't put the speedo out that much. Plus you have to wonder how accurate the speedo is from the factory. When I set my Evo dead on 120km/hr (OEM size tires) and my dad sets his R8 dead on 120, he has about 3 car lengths between us within a few min. I wouldn't worry about it to much...

 

When you change tire sizes and rims it kind of does make a difference. For me it's just one of those things I would like to keep as accurate as possible.

 

Well, it is not a problem to calculate the difference in percentage and count with it while driving. But as noted above - the difference within usable rims and tires would not vary so much from stock.

 

I have seen on the forum before, someone posted a calculator for this. what you do is put in your oem sizes, then put in new size. it will give you what your speed should be in relation to oem size.

http://www.1010tires.com/TireSizeCalculator.asp