i'll add another thing in , i actually temped the engine yesterday after my TQ in my pro buggy heat , wich i very rarely do ,most of the times i leave the temp gun at home..i don't use it to tune..i just listen to the engine , anyways , she came off the track at 185 degrees..my buddies STS came off the track at 190..

i don't know about others running these STS D21T's but i found it to be a very cool running engine , i have won and TQ'd races with the temp not even hitting 180 degrees...on a track that is quite a high speed track with lots of double/doubles in it , wich you need to have a good running engine for or you just won't make the 2nd set of doubles..