I have the exact same issue. Been fighting it all summer. I have ECP radiator that I installed last year with a shroud and 17" flex fan. Ran 195-205 without a stat. My dual electric fans are spal 12" fans and cool great when stopped or driving slow and it will pull temp down from 220 to 205 when I stop. I drilled more 1" holes in the shroud for more air flow to no avail. Jones pulleys sold me a restrictor that mounts in the lower hose, but it did nothing for me. My wp pulley is 4.5" and crank pulley is 5.5", so i'm over driving water pump and it will not cool at speed. I have a pump gas 511 filled with hard block 3" from the deck. My Moroso WP and flex fan will cool good enough, so once I get to the track for a time on the car, the electric fans are coming off.
