I have a Whipplecharged 502 Mag EFI and use a drilled out thermostat. In the 1000 Islands the engine runs at about 120 degrees in the spring ... reaches 140 to 150 in the summer. I also use an offshore water pickup and strainer.

Cayfomula,

What spark plugs are you using? I had the carbs set up by Teague for the superchargers. They are 750 Holley's. I am going to install thermostats. The motors need some heat.

Wilerty, do you remember the size holes that were drilled in your thermostat?