Doubt its the radiator alone. I run a Champion 3 core in my 512 never gets over 185. I run the same shroud w/a derale mech race fan. Didn't worry about the gap.
I've driven it on the street and hot lapped it at the track in low to mid 90 degree days
Same here. Haven't had any cooling issues with a few Champions. I agree that his is probably another issue.
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