This one may be towards the Racers on here i am calculating the expansion rates of different Piston alloys, in Particular 2186 and 4032. i can only estimate the temperature of of the pistons during Racing but i would like to see what you guys think the temerature would be? the hottest i have estimated my oil temp on track during a hot day is about 110 celsius(230F) and i can estimate that my cooling system is around the 95C-100C(203F-212F) mark as the fans kick in at 98C. what would you guys estimate the Cylinder walls and Piston Temps to be. obviously the Pistons would be hotter then the walls as they have less chance of disipating heat.
Sean

 

Piston temps vary a lot (a couple of hunded C) from the crown to the skirt. If you are tring to calculate the expansion there are a lot of other vabilble - some pistons even have inserts to control expansion.

 

i knew you would know chris, i figured there were a lot of variables involved. i have some figures from JE explaining the thermal coeficient of linear expansion. ie, the rate at which certain alloys expand.
with piston temp Difference of 160F(from assembly spec to operating temerature) the average coefficient of 2186 is 0.0000124" per degree. so using this info i can expect:

4.094(piston size)x0.0000124"x160F=0.008122" this is what the Piston will expand by between start and operating temp. so the pistons final size will be 4.102122"
if i ghad a better figure for piston temp i could be more accurate