I have homemade caltracs with 255/65/15 tires. I have removed a leaf from the leaf springs, as suggested by stangnet members. I still do not notice any difference in 60ft times with the caltracs. I actually could not even reach a 2.0 with them as I could without them. I have some pretty new Dunlop GT Qualifiers that have a tread rating of 440. I know this is not ideal for racing but I would have expected something from the caltracs since everyone who has caltracs says they are great. I borrowed my brothers wheels which are in ok shape, 245/40/18s with a tread wear of 300 and I could not beleive how much better they stuck to the ground. My tires spin if I launch at 1500 and then again once I reach 5000 rpm. My brothers tires I could launch at 2000 and did not spin on the top end. Do my caltracs not work cause my tires just suck?
