Build you a cardboard shroud let it idle in the driveway and see the difference. I bet the fan is not pulling enough air through the radiator at idle. Will it hold a piece of paper to the radiator with it idling ? If not ,you don't have nearly enough air flow.
A popular misconception. Spark Plug heat range has Nothing to do with engine temperature. Heat range is the speed at which a spark plug can transfer heat from the firing tip to the cylinder head water jacket and into the cooling system. The heat transfers regardless of heat range, it only determines how quickly it does so. This will not change the temperature that the engine runs by any measurable amount. Choosing the right heat range is crucial for high performance engines. If the heat range is too cold, the spark plug will be unable to properly self-clean by burning off carbon deposits. If it the heat range is too hot, your engine could experience detonation, pre-ignition, or power loss. Most spark plug manufacturers recommend that the tip temperature remain between 500° C and 850° C. Heat ranges are designated by each spark plug manufacturer with a number. In broad terms, spark plugs are often referred to as “hot plugs” or “cold plugs.” A cold plug has a shorter insulator nose length—the distance from tip to spark plug shell—and transfers heat rapidly from its firing tip to the cylinder head water jacket. Cold plugs are ideal for high rpm engines, forced induction applications, and other instances where the engine produces high operating temperatures. Conversely, hot plugs are good for applications that operate mainly at low rpms. Because they have a longer insulator nose length, heat is transferred from the firing tip to the cooling system at slower pace. This keeps the spark plug temperature high, which allows the plug to self clean and prevent fouling.
As others have noted that fan is WAY too far away from the radiator. You want to have about a 1" gap between the fan and radiator. Put a spacer in there for starters. If that is not enough, then add a shroud (which you really should do regardless). Set the timing closer to 14° initial without vacuum and hook the vacuum line to ported the ported vacuum port on the carb. Also you timing is coming in a bit quick, I would look to have it all in by around 3,000, not the 2,000 you indicated. Put heavier springs in the advance.
Antifreeze does not transfer heat as efficiently as water. But this is not his problem, and should not be a problem for anyone. As you pointed out, there are corrosion inhibitors in the antifreeze that help keep the system clean, which keeps the system efficiency better than a system without. The advice given to reduce the ratio of antifreeze is unfortunate bad advice that just keeps going around.
''''Also, you said you are running a flex fan Those things seldom work Try a good 6 or 7 blade steel fan along with a shroud.'''' Yep.
^^^^^^^^^^^^^X2 Agree 100%: In 1977 I bought a 1973 GMC 4X4 p'up that had been well cared for on all maintenance, and I drove it for over 20 years and kept fresh antifreeze in it, drain and refill every few years, always at least 50% antifreeze often higher. The truck was driven all over "hell and high water", and much of that water was sea water at the beach and out on the flats at low tide clam digging. Truck rusted out to point no longer usable on street and I junked it and kept the engine, which was a 350 4 bolt main. About 2009, I started building my roadster, and decided to use that engine out of the 4X4 to build for the roadster. Tore the engine down to the bare block, and there was absolutely NO RUST in the water jackets or even on the back side of the core plugs when I popped them out! So don't go blaming his problems with overheating on antifreeze, I call bullshit on that.
Yes that fan! I'm a firm believer in STOCK type stuff, and a shroud is a must. 3rd thing would be a 180 to 195 thermostat. I believe your problems would be over. And I do practice what I preach. Pat
Many thanks to all the SMART people here on the forum. I fabricated a cardboard fan shroud yesterday and installed on the radiator with tape. It wasn't quite deep enough and the fan still was over an inch outside of the shroud, but I did see temps drop 10-15 degrees at idle. Before the shroud I was hitting 230, and with this setup I was down to 215-ish. I'm sure a better shroud and fan will DEFINITELY make a huge difference!! I'll update when I get the real deal made and installed. Shroud by krbarnes posted Jul 7, 2017 at 7:53 AM
I have a "cooling components" electric fan and shroud that is in my '40 the total depth is 2 5/8" of the unit should fit with clearance, or if you are using a "long SBC" water pump use a short pump it is at least 1" shorter (maybe 1 .5") and that will give you clearance. I have added all the correct '40 sheet metal and added a metal cover between the grill and radiator to force the air thru the radiator . Good luck
Shroud will make a huge difference when ideling. I made one out of fiberglas. you could also add an electric fan
How loud is your fan? When I first built the car and was using the original radiator, I bought a 16" Maradyne electric fan from Summit. It was so loud that I couldn't hear the engine over the whine of the fan. That's when I pulled it off and went with the flex fan. To tell the truth, I never even drove it with the electric fan, so I have no idea if it cooled better than my current set-up, but I'm sure it probably did.
Seems you have the problem solved. If you can incorporate a tube type ring around the fan into the shroud it will prevent air from sliding off the end but it might not be necessary. A flex fan should be best at low speeds and flatten out on higher speed where the vehicle speed provides the flow.
The fan is pretty quite I have NO problem hearing the engine, I would say it is no louder than any standard OEM electric fan, in fact my daily driver is a 2017 VW GTI and it is louder than the cooling components fan. PS NOT Cheap but it works I used it as 2 of my budies have the same set up in their '40 fords which can be somewhat dificult to cool.
If youre having issues with space from water pump to radiator, use a short pump from a 327 corvette motor. Late 60's early 70's. Before i installed mine i was going to have to move the radiator. Much less of a headache in my opinion. FYI, my '50 chevy with a V8 swap did the same thing yours is doing, i added that short pump, an S-10 clutch fan and fabbed a good shroud. It put the gauge where i wanted to see it. After almost going crazy over it, my problems were over. I dont think i was actually overheating, nor are you, but the gauge tricks you and you start to panic at a light. I even tested my temps with one of those point and shoot temp guns and while the gauge read "hot", my ACTUAL temps were perfect. Dont let it make you crazy, youre on the right track. Sent from my iPhone using H.A.M.B.
You seemed to have found what took me two years to figure out. We have a 50 chevy with the same setup. What I did find was that the 50 Chevys were set up for narrow in-line sixes so there is not a lot of 'air room' around the motor to help the cooling, as you found out a shroud is almost required Keep on it
Actually your shroud is about right you do not want the fan inside the shroud. If the hold you hand above or to the side of the fan you will feel a lot of air if fan is inside the shroud that air is trapped inside the shroud and recirculated.
Sound like you're on the right track. I took notice of this thread because I had similar issues with my 61. The flex fan it had was the first thing to go in the trash and I am currently using the same fixed-blade fan from summit you showed. I would, however, keep your vacuum advance on manifold vacuum but get an adjustable diaphragm to reduce the amount it is adding as well as slow down the mechanical advance rate.
Good electric fans from Champion Radiator. I've got a dual setup on an O/T Torino. Not loud at all. http://www.championradiators.com/SPAL-low-profile-fans Mike
I know a local sporty car guy that built a Porsche 914 (Sorry Ryan) with a mid-engine s.b.c. that's Right against the driver seat. No room for water pump let alone fans & shrouds. He tapped out the water pump holes & used pipe nipples & then 90 degree fittings to a remote mount electric water pump. The radiator is up front & runs at 180 all day. Even then the engine rubs a hole in his seat back. You got all kinds of room! Oh yeah this thing is a screamer!!
You're on the right track....Like many have already said, lose the "flex" fan, get a decent fan shroud, and you can always install a electric fan in front of the radiator where you have tons of room and use it as a pusher for those "parade" cruises.
Actually you want no more than 1/3 of the blade width INSIDE the shroud. More than that and you will not have good air flow. Go look at your OT daily if you don't believe me.
I made a sheet metal fan shroud, replaced the 160degree thermostat with a 180, and replaced the flex fan with a 6-blade fixed fan. 20 minutes of idling in my garage with the front of the car about 2 feet from my workbench (not much air movement up there) -- temps never went above 190. I think my problem is solved! Shroud2 by krbarnes posted Jul 17, 2017 at 10:57 AM Shround4 by krbarnes posted Jul 17, 2017 at 10:57 AM Shroud5 by krbarnes posted Jul 17, 2017 at 10:57 AM
With your engine at idle , put a window fan in front of your radiator blowing in . If your engine temp goes down ? There is your problem .EZ test .
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