Just throw a lower temp thermostat in it too for safe measure

 

What direction does your engine rotate? Clockwise or Counter-clockwise? What direction is the fan clutch you purchased supposed to rotate CCW or CW? They look the same but a mechanically designed to only engage correctly in one direction.

With the engine off and free spinning the fan in the direction it normally rotates, how many revolutions of the fan do you get? More than two or three is excessive slip of the fan clutch which means either the clutch is worn out or could be spinning in the wrong direction.

 

Timing is set to 8 degrees BTDC at 500 rpm Total timing at 3500 rpm is 53 degrees. Temp of top radiator tank is 192 degrees. Lower tank temp varies between 125 and 135 degrees

 

Woah....

8 to 12ish BTDC is great you should be running 20 deg of advance for total timing of 32 to 36 deg maximum. If you have vac advance disconnect when checking. With Vac the maximum timing should not exceed 42 to 46. Im assuming the 53 is with vac also correct? In most cases you want timing all in by 2000 to 2500 rpm

192 Top and 125 bottom would indicate: 1) normal operating temp 2) a properly functioning radiator .

so that 53 deg is a bit excessive if you are running vac. If you aren't running vac advance then its straight murder. I would like to see 12 idle, 20 advance + 10 deg vac over 10inhg. thats 42 max you're 11 over that

 

Oops. Forgot to disconnect the vacuum advance. Might check again.

 

Went and checked the total timing at 2500 rpm vacuum advance disconnected and it was 25 degrees. Is that reasonable?
For DERFOO I believe all 289 engines turn clockwise (standing in front of the car) and the fan blade only turns about 180 degrees when pushed with the motor cold and off

 

Did it advance beyond that? You indicated that it would advance to 3500 RPM maybe further. At what RPM does it no longer advance (all in rpm) and what is total timing at that RPM with Vac disconnected.

It appears that a bunch of excess timing hiding some place if you got 53 previously.

 

1500 RPM 20 degrees
2000 RPM 22 degrees
2500 RPM 22 degrees
3000 RPM 25 degrees
3500 RPM 25 degrees
4000 RPM 27 degrees

Al of these are probably +- 2 or 3. 4000 is the max rpm I wanted to do

Are we getting of subject? How does this effect engine temp at idle. Thanks for your comments

 

No it really wouldn't effect engine temp at idle as thats based on your initial timing which is about 8 which is maybe a bit low but totally reasonable.

It could cause engine damage under load but that timing curve is so goofy I dont really know what to make of it. First of all it shouldn't just keep advancing as you keep adding rpm. It shouldn't have 53 deg total with vac.
There is an issue with your distributors advancing system its missing pieces like the adv stop and its using springs that are too tight. It should look more like this:
1000 RPM 12 Deg
1500 RPM 20 degrees
2000 RPM 28 degrees
2500 RPM 34 degrees
3000 RPM 34 degrees
3500 RPM 34 degrees
4000 RPM 34 degrees

So some how vac advance is adding 30+ degrees of advance at 3500 RPM or perhaps any time its running. This is not good.

Go ahead a disconnect the vac line and plug the line with a small screw or whatever. Just drive the car around with out any vac advance. If those numbers are repeatable it may cause it to run better or cooler under normal driving conditions. I would feel a lot better with the timing at 22 deg around town vs maybe 52 that may not retard or advance repeatable.

A second thing that catches my eye is the rad temps that upper vs lower that you provided. Assuming you took the measurements at the same distance (say 3") you should get an accurate temp differential 60 to 70 degrees in your case. That's actually really good. It makes me think perhaps your temp gauge is being fed improper data or isn't displaying good data properly. I consider the thermostat housing to be equal to engine temp and most engine temp sensors fit near this housing. Once the T stat opens and the engine it at operating temp (maybe after a test drive with the vac advance disconnected) take a look at your primary engine temp gauge (the one that told you 240) lets say it reads 215. then go and measure the T stat housing it should read between 210 and 220 when measured from 2" away. Assuming the T stat housing is not shinny like chrome or a polished metal (which causes inconsistent and inaccurate IR readings) the value you see on your IR temp gun is engine temp. If your primary gauge says 210 and your IR temp gun says 215 then 210 to 215 is your engine temp. If your primary gauge says 210 and your IR temp gun says 190 then your engine temp is 190 (again no shinny chrome T stat housings)

If the IR temp gun shows normal temps and your primary gauge does not and reads hot. This is an option. good gauge This should fit into the place of your current temp sender and provide real time engine temps accurate to within 0.10 deg they are absolutely fantastic for the price. If you dont like digital you can just remove it when testing is done or hide it in glove box. a warning alarm for high temp can be programmed into the meter and a high point set the alarm can be a light or a buzzer or both (gotta buy separate they use 12v).

 

I did also check thermostat housing temperature vs temperature at the intake where sensor is screwed into intake with ir thermometer. Temperature vs virtually the same at any operating temperature.

I neglected to mention earlier that when the engine was rebuilt I had the re builder put in a slightly more aggressive can than stock. Would this affect operating temperature?
Cam specs
Part number MC1734Camshaft Specifications:

• Stage: 2
• Duration @ .050": Intake: 204 Exhaust: 214
• Advertised Duration: Intake:280 Exhaust: 289
• Valve Lift: Intake: .448 Exhaust: .472
• Lobe Separation: Intake: 108 Exhaust: 116
• Power Range: 1500-4000
• Idle: Smooth

Thanks for comments.