ZO6 Speedo adjustments w/taller tires?

[Redline MS]

Nice! Thanks for the CLEAR explaination!

Howard

[EC_Tune]

Your very welcome...

EC

[HNK]

Fill in these areas and your good to go.
Or just use 26.85 with Gear ratio of 1
Comes out very close...
EC

Doug,


Long time, I just replaced my tires with the Nittos which are 345s and taller than stock. in their specs sheet, it says the inflated diameter is 27.17 and revs/MPH is 765. Should i use those figures?

I did use what u suggested above but still when i accelerate and let off, i get the engine drag control active msg. Any suggestions?

[EC_Tune]

Do a roll out measurement to see what the rolling diameter is. Then you can calculate the exact tire height. The Engine Drag Control thinks that the rear tires are slowing down more than the fronts. It's an ABS issue as the front to rear tire height ratio has changed. And your tire height may be off a bit in the PCM.