What I would be concerned about is that it does get hot - why? I am running a pretty quick motor in my 4wd, and haven't cut any of the vents out, and it only comes off at a normal hotness... 100 - 110 F .. even Vernon is running his Cat SX with no holes cut in a heavy Nimh car, and he has fried nothing recently (suprisingly).
Which 4wd are you running to have such limitations in gear ratio's? Im finding that part hard to believe, sorry. I know you race a popular car Dave, I just can;t remember which (you've had a few
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