Definitely use the 160 deg thermostat of the two you have. I use a 180 deg thermostat in all my vehicles and if running thermofans have a thermoswitch kicks in at 190 deg and stops at 175 deg.

Good luck.

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Love cruising in a bare metal Val!

So I pulled the radiator and put the original 4 blade fan back on and removed the 12" electrical (not 10".) It was a very tight fit between the fan blades and the radiator on the order of 1/4' to less than 3/8" but it did not hit.

I did not reinstall the thermostat yet will check the 160 degree in a bit.

I fired it up and ran it for almost 15 minutes and the stock temp gauge went to the far side but not out of the acceptable range marking. The aftermarket temp gauge went to about 200 degrees max and then I shut it down. So ths is an improvement.

Ill check the thermostat and reinstall it and check timing and carb and recheck valve lash and report back.

Cheers!

_________________
Psychics will soon lead dogs to your body!

1963 Dodge Dart 270 convertible

Stock fan moves a lot of air compared to most electric fans 16" and under.

200 degrees is not unreasonable for new rebuilt unbroken in engine sitting parked. When driving down the road, cooling should be a bit better.

I use a 190 or 195 degree thermostat I can't remember which, and temp gage sits about needle width east of straight up and down at about 75 ambient degrees, and a little more east in high 80's ambient when under way. Engine is turning 3000 rpm at 60 mph, has 9.5 cr, over sized valves, high lift cam, Holley 390 cfm. and puts out about the same power as a stock 273 or perhaps 318.

A few things to ponder:

Using thermostat rated below 180 degrees can cause sludge build up particularly during cool weather, and no thermostat will cause sludge buildup in engine. Engine has to get warm enough to boil off moisture, and any unburnt fuel that finds its way to oil pan; 180 degrees and higher is the magic number. Factory recommends 180 degree stat in summer. In the north we always installed a 190/5 in the winter to prevent mayonnaise forming on valve cover oil fill cap and top of dip stick.

Cooling system works better when fully pressurized to around 16 psi with 50/50 mix of antifreeze. Pressure & antifreeze raises boiling point of coolant allowing for more efficient heat transfer from cast iron surfaces into coolant because there are no small steam bubbles forming to insulate iron surfaces from coolant. The larger the "delta T" (differential between coolant and ambient air temperature) the more efficient excess BTU's can be cast off by radiator. Also, 50/50 mix antifreeze retards cooling system corrosion, and lubricates water pump.

You are making progress.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

FYI- the stock fan on an A body is supposed to sit less than 1 inch from the radiator. Sounds like yours is good.

I agree- I run a 195 thermostat year round. 200 degrees for a new engine is not bad.

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Casually looking for a Clifford hyperpak intake for cheap.

Cool, I rechecked the thermostat I have and I have two 195° and the 160° is actually 180° so I will use this one.
I have antifreeze and will have it at the correct mixture once I am happy with not having to remove the radiator and hoses and loosing the coolant while troubleshooting. So far I have probably dumped several gallons of water during the troubleshooting and its much safer for the environment compared to the antifreeze not to mention cheaper.
So I will head out and put the 160° stat in and recheck valves and timing and carb setting and at this time feel pretty good about the results as usual my caveat of barring something happening of course.
I will clean up the rest of the little things and probably be back in the tranny forum to wail my list of woes soliciting the great help on /6![/img]

_________________
Psychics will soon lead dogs to your body!

1963 Dodge Dart 270 convertible

I agree with increasing the pressure. Have gone up to 14psi without any issue.

Stick with it - you'll get there.

Good luck!

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Love cruising in a bare metal Val!

Thanks Max, thanks all of yall, I certainly appreciate all the wonderful folks out there and the experience and help yall give so freely!
Cheers.

_________________
Psychics will soon lead dogs to your body!

1963 Dodge Dart 270 convertible

It is running pretty well now, I added tranny fluid and it goes forward and backwards. I found the cooling lines on the tranny leaking so got them tightened up, looks like one might be cross-threaded but hard to tell from the garage floor looking up, I am keeping an eye out for leaks and so far nothing noticeable.
Working on the kickdown linkage and springs for the carb and linkabe now, a little hesitant to drive it around my cul-de-sac as of yet but trying to work up the nerve! My wifes Highlander is in the way right now is my excuse!
Nice sunny day here in Seattle.,
Cheers!

_________________
Psychics will soon lead dogs to your body!

1963 Dodge Dart 270 convertible