427 runs too hot

[jojoegen]

I have a shell valley cobra.I have read everything I could and this radical 427 Pond iron block with edelbrock heads,560hp will run too hot at idle.Go figure.Tested engine heat with heat gun.does not show overheating so tested guage and sending unit with another and it is running hot.Checked lower rad. hose for collapsing and it,s good.It has a Kirkham expansion tank.Timing is 36 all in.Fan has no shrowd.16" puller fan works great.It's a new Keith Kraft engine and set up by him.I,m thinking that the March pullies are the problem.They are their underdrive which looks like they are almost the same diameter.They don't have anything more for this engine.I need to know where I can get a larger crank and a smaller waterpump alum. or shiney pulies that will let the pump run faster.If I look in the expansion tank very slow flow.Maybe a thermostate opening is too small..It does work (180)but maybe the opening size is too small.I read about using a dodge therm. and cutting the edge down will work beacuse the therm. hole is larger.Any help would be appreciated cause I'm frustrated and only used it once since new.Thanks my friends.John