Originally Posted by
EDWARD2003
I'll be running modified (3.5) and wondering what tire diameter sizes I should start off with on low-medium grip CRC carpet. What are your thoughts?
Originally Posted by
andrewdoherty
Smaller than you might think. Of course it depends on your wheel size, but i wouldn't start any bigger than 42 mm and thats even pretty big. In mod tires are usefull 1 to 2 runs in my experience. start them larger and you will grip roll. start them too small and you will run into the rim before the 8 mins are up. If I had to say an exact number i'd go with 40.9 rears and 39.9 fronts.
For a track with low to med grip
I would true a few sets to 42Fr 44Rr, take a few runs on each, then true to race size
Normally it takes a bit to get used to the track, and fine tune some things on the car, so I'd rather not use 1 run tires for this
Smaller is almost always going to handle better though, and Andrews sizes are the go to for maximum performance at a high bite track