I have auto-xed Kumho MXes for 2 seasons now and have been very pleased with the tires, but have had some trouble with overheating. I usually start them at 36f/36r, then drop them - after they've warmed up - back to 38f/36r. Saturday, I decided to run them 40f/38r, and man, did they heat up fast. Grip went away and they came in smelling bad after even one run on a tight, technical course. They didn't blister, but were feathered and wouldn't hold the track. So, I let 'em cool and dropped the pressure back to 38/36. Bingo, times dropped nicely. I've noticed them losing grip and getting smelly toward the end of the day at a nice hot location like Anderson, SC in May and July, too. At this point, my instinct is to stick to the lower pressures, since they don't heat up as bad and the grip is fine. Anyone else notice this with their MXes? Where are other drivers setting theirs? I keep hearing they like 40psi or so, but that's not what I'm seeing. PS, No need to tell me my balance is off with the f/r differential, that's what I need to keep the tail end where it's supposed to be. Running even pressure f/r makes my stock 95 Z07 *very* tail-happy.
I dont have MXs. I have Falken 451s (great tire) and I run them lower at 34... they heat up pretty quickly and by the end of the run they will be 36... or even higher depending on how hot the track is. I used to run Kumho 712s and they were crap.
INSIDER INFO: I had an appointment with a manager at Falken the other day and he tld me that they were going to come out with Azenis in 275/40/17s very soon. I told him that I was in need for new tires and would need them if I ran one more track event. I asked him if I should wait for the Azenis... he said yes!
I started out running 36 all round in my MX's. They were moving up to 38 - 39 hot. I tried lowering them to 32 front and 30 rear cold which had them running around 35 hot in front and 33 hot in the rear. I saw a big improvement from that change. The MX's don't seem to work too well with the extra pressure.
Corvette Store
Kumho MX overheated on auto-x: tire pressure?
