ORIGINAL: mozzzy_2000
.27 is simply not big enough to give it ample cooling. Its smaller than some racing 21s in some case. I recently found a giant cooling head that fits the .27 & now I am running the engine at 180F!!
A: Racing .21s create a lot more heat than the .27. engine size alone does not dictate its cooling needs-its design, porting, and materials dictate that.
B: at 180 degrees you're doing more harm to your engine than you are running at 280 degrees.
C: cooling head size ALSO does not dictate cooling capacity by itself. again, it's the design of the head and materials (for the most part)
So anyway engine temps are not always the be all & end all when it comes to tuning.
They are never the be all/end all when it comes to tuning-IMO, temps are lowest on the priority list, but you DO need to make sure you don't reach the magic 300 number.