71stockray

This is continuing saga the ongoing of the highway running hot problem of the pervious posts. new radiador(copper)new stat(190)replaced all foam around radiador and hood. Installed new chin spoiler, new antifreeze, 2 full flushes of system. Vette can run back roads and around town all day does not go over 215, 2 hours on secondary mountain roads last week no problem. 15 minutes at 70 MPH and is at 230 and climbing. Check with IR gun, it`s right on. This is only a highway extended high RPM problem. Also replaced vaccum can on dist. and set up for factory 8 BTDC, 600 idle, 30 dwell. Today the outside air was 35 degrees and still almost hit 245. WTH is going on here. I am really starting to get nuts with this. Not to mention going broke. :confused: :mad

flynhi

If your lower radiator hose doesn't have a spring inside to prevent collapse under suction, that may be your problem.

brookman

That would be my vote. At higher rpms the bottom hose is under vacuum and will collapse if the spring is not in it.

Fevre

Check the lower hose for the spring that keeps it from collapsing at higher rpm's and also check you clutch fan for proper operation.

Smokehouse69

I know after all you've done it must be frustrating and this is a long shot, but you could be air locked. Try jacking the front end of your car up so that the radiator fill is definately higher than the engine. If you have any air trapped in the system.
Also I have another long shot, have you checked your balancer, if it has slipped you might be running way more advance than normal? I don't know if Dwell has anything to do with it, but I always thought that 32-34 was correct for a points type iqnition.
Good luck!


[Modified by Smokehouse69, 10:32 AM 10/3/2003]

jerryp58

Here's a shot in the dark...

If it's on there, is there any chance your heat riser is jammed and is overwhelming the system with excessive heat passed through the manifold?

I would think you'd have fuel percolation problems before anything else, but it's just a thought :confused: