Everything is brand new, still overheating.

[Jim S]

I pulled the trigger and bought a 350 long block freshly professionally rebuilt.  I have a brand new aluminum Avanti radiator. I have a heavy duty racing water pump and electric fan.  The needs to be run a 2,000 rpm for 30 mins to break in.  I can't run it for 15 mins without the temp guage pegging to 240 and it overheating. I've purged the air out as well.  I am lost why this thing won't run cooler.  If I can't fix it soon, it will have to be sold at a huge loss.  A friend told me that Avantis have an inherant air flow problem through the radiator.  He said some people got more flow installing an air dam.  Has anyone tried this? Or does anyone make an aftermarket add on?

 

Edited 4 hours ago by Jim S

[Gunslinger]

Yes…an air deflector directs more air to the radiator that would otherwise create turbulent airflow under the car.  It serves no purpose idling but really helps at speed.