Classic/Antique Car Repair: my small block overheats, dirt track car, stock dirt

Question
Here's what happens:
My Nova hobby stock dirt track car with a small block 350 overheats at idle.  Reaching up to 270.

Here's what we have checked:
Water flow is good, Cleaned radiator, and hoses
no visable leaks around gaskets
Timing is good
plugs good
changed the fuel pump
Had heads checked, they were refreshed and are fine.  They only had 4 races on them before this.

Now what should I do.  It still gets hot at idle around 230 after 5 minutes.

I am one frustrated racer.  Can you suggest something?


Answer
HI James;
         Over Heating- OK , did you remove the termastat ? I would take it out if you did not . Also - do you have a good fan ? or clutch fan on it . Is the space from the fan to the rad. close enough ? Is the rad. cap bad ? are any of the hoses being sucked closed when engine is running ? if the thermastat is still in - take it out .
let me know how you make out ok.
Roger