As per subject. Car is running like a top and feels good, but wow does it run hot (temp gauge from just below hot normal range to actually touching the "H").

Coolant is fine. New water pump, hoses, etc. Cooling system not the problem.

Timing is about 12 before. Runs great, but scary temps. Should I just retard the timing a bit? Any ideas?

I would retard the timing until you can feel power drop off...then add a little back. What you reallly want to check is total timing without vacuum.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Go back thru the cooling system again...
Test the thermostat's opening point.
Cross-check the gauge reading with a different gauge / thermomotor.
Inspect the radiator's core tubes, see any plugged cores?
DD

Thermo is a 180 and is brand spanking new. I had my rad cleaned and redone by a rad guy like 3 weeks ago. So plugged cores definitely not the answer.

Thanks for the ideas!

New thermostat doesn't necessarily mean working thermostat. Thermostat could also be backwards. Could also be jammed by slipped thermostat gasket. Could also be…

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Ok, a point has been made re the thermo. I'll crack er open on cooldown.

Thanks!

how does it idle
high?
vac leak on carb/intake makes em run hot, but the idle is affected.

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slant six's RULE!
http://www.usajon.com

Idle is pretty smooth overall. Plus, I don't think it would run THIS hot and feel this responsive with a big vacuum leak.

Looks like Doc and SlantSixDan may have struck again with their encyclopedic knowledge. I clearly have some kind of cooling issue. Retarding timing just made the car sluggish, and once I got to highway speeds, blazin' hot.

Another oddity - between 0-45 mph, runs in the middle of the temp band. But once you push up to 70, it's danger time. And, it takes a while to get back to normal at 40.

Looks like I'm replacing a thermo tonight. Here's hoping!

Inspect the radiator cores when you have the coolant drained.
A "new" or cleaned radiator will quickly clog-up again if installed in front of an older engine full of rust and crud.
DD

High-speed overheat = water flow or water cooling problems, not airflow problems. I think you'll find a faulty thermostat or a (re)clogged radiator. You may have to clean the engine of accumulated gunk and re-rework the radiator.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Might be a bad water pump. You said its new could have
A junk one .

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Wanting a 3 or 4speed slant 6 car .

So Thermo was replaced. Emptied and flushed rad with a pressure hose. Now runs a little cooler, but not by much.

I'm beginning to doubt the water pump, but at this point I'm doubting everything. How difficult is it to manufacture a water pump? Or more importantly, what are the odds I have a bad one right out of the box? The math doesn't make sense.

Also, I should note that I am running a setup similar to Aggressive Ted, with the two fans. Still a little too hot for comfort.

It's not likely you've got a bad water pump.

Tell us about your two fans, please. Are you sure they're both the right way round, not trying to push air forward through the radiators as the vehicle's forward motion is trying to push air rearward?

The fact you got a little result out of a quicky garden hose radiator flush suggests a proper cleanout might still be needed.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Have you considered the possibility of the bottom radiator hose collapsing (sucking in) at speed?
Easy to check with a few revs. just make sure the thermostat is open when you do the test.

regards,Rod

See here re collapsing radiator hose.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.