That is with a fixed timing motor. Plus on the huge Hudy arena track, they were running as high as 2.2. XR tires are also smaller in diameter than pit tires too so I usually gear it a tooth or two higher.
My 2.7-3.0 recommendation is primarily for adjustable timing motors.
Yes, fixed timing. Do you know what the fix of the Hobbywing is. I am guessing 27,5 degrees but I am not sure. With variable timing motor what endbell timing you would suggest to run with 2.7 ratio?