IMCA G60 Help Please

[kfactor239]

When are these tires worn out? I have been told they are good for 6 races but is that a whole 28 lap night of racing (5 hot lap 8 heat 15 feature). My tires have anywhere from 3 to 4 nights of racing on them and from 26 to 98 laps total on them. What about tread depth? I have 6 tires and the tread depth rages from .098 to .128. I grind my tires before I race on them for the night. They still seem fairly soft but I haven't ground them again yet.

[SRXSRULE]

A lot is going to depend on the track conditions. If its dry/slick I never got more then 2 nights out of a RR and maybe 3 out of the LR, and thats grinding, siping, and flipping the tires around on the wheel after the 1st/2nd night just try to get one more night out of them. If its been a cool, rainy week and the track stays tacky all night you might not even wear the tires much, but that rarely happens.

You should add a tire durometer gauge to your tire tools. then you will know when they are getting hard. check them when they are new and after each night. I doubt you will ever run them more then 4 nights. tread depth doesnt mean a whole lot, the nice square edges on the tread blocks and square edges from siping is where your grip is going to come from. when you grind your tires you only want to remove a small amount of rubber. you just want a fresh surface, and leave nice sharp cuts in the rubber with out tearing the tires all to hell. also think about which tire you are grinding and where its going on the car. front to bank and left to right, you will want to change the direct of your grinding. siping can also help a tire run cooler so play around with that. the rear tires need all the cooling they can get and the RF could use some extra heat .

Figuring out these tires is 1/2 the battle......good luck. Eric

[kfactor239]

Thanks Eric. I'll definitely get a durometer and check them every night of racing. Another aauestion do you race on brand new tires? I've heard that you should grind them and just run hot laps on them the first night. Something about they need to cool completely off after their first heat cycle.

[SRXSRULE]

I mount brand new tires, then wash/scrub the sidewalls and tread to to get them good and clean and remove any oil on the surface of the rubber. Then I lightly grind them, and then do my siping.

Some guys do like to heat cycle them before running them in a feature. Hot laps isnt going to do this for you, its too short and the track is too wet. You either need to run them in a heat race on the rear, or the RF in a feature. I never seen any increase in tire life so I stopped doing it. I always have a set of heat race tires and a set of tires for the feature and dont mess with any grinding at the track. Eric