LS2 Garrett 88mm Meziere WP 55gmp coolant mix (also have tried water additive) idle gets around 205ish Both cars have the same radiator same fan same -16an radiator hoses......car would get to around 200ish with the stock pump and a t stat with drilled holes but I had such good luck with my set up I said let’s try electric water pump and well guess we got greedy lol.