I would think this setup with this engine shouldn't have any cooling problems. I would appreciate any thoughts or insight on how to address my problem.
Actually, as you have found out, it's a terrible set up.
My thought is to return it to stock.
My insight is to respect the OEM design.
My thought is;
I would set it up with a big 7-blade direct drive fan in a matching shroud, and jam that rad up tight against the core-support. Then, when you have figured out what works, only then can you start experimenting, cuz after that, everything will be a compromise.
BTW-1
check out your Air-cleaner. It is sucking HOT air in an endless loop , round and round goes the heat, hotter and hotter goes the coolant.
BTW-2
Nothing builds heat better than retarded low-rpm ignition timing.
At idle, your engine may want 25 to 35, or more degrees of timing. It will tell you so by increasing in rpm continuously as you add timing, until it plateaus. As it does this, it will make ever more idle-power. which is gonna cause other issues so you can't really run a 300hp engine at those big numbers, nor should you want to, cuz as soon as you put it into gear, with a stock-type convertor, it'll probable either bang into gear or stall. >>The point is that choosing an idle timing number is always a compromise.
> the first time an engine really cares about timing is at Convertor Stall. She wants as much as possible until she detonates when you floor it. Depending on the stall-rpm, and combustion-chamber design, and the air-temp going into the airhorn, this max WOT timing could be anywhere between say 18* to even 35* degrees. The more the engine likes, without detonating, the more torque it will make, and the harder it will take off. But if it detonates too hard or for too long, engine-parts break or burn up. So then, every precaution has to be taken to prevent detonation.
And of course iron-headed street-SBMs don't usually like more than about 35* Power timing, usually no earlier than about 3400rpm. and seriously, there is no point in pushing that edge, cuz with street gears, and topping out at 65 mph, you'll never feel those last three degrees, cuz you'll be lucky to see 7hp out of it, and the long term risks are just not worth it..... IMO..
The point is this; as far as I'm concerned , at your power level, your engine needs a two-stage timing curve. Stage 1 is from idle to stall, and stage 2 is from stall to 3400. Your combo does not need nor want 20 degrees at idle; but it does want more than 5 degrees. Typically, for 300 hp, 8 to 14 is gonna be well-received. But what you can actually run, will depend on what she wants at stall, and that will depend on the actual stall-rpm.
The whole point is, that if you got a good ear, you might be able to push the detonation edge; but for most of us, minus 3 degrees will be close enough. and
YOUR engine is not your buddies engine. Your engine will tell you when it gets too much so don't go there.
A smarter than me man(there are lots of those) once told me, that among 10 identically built assembly line engines, you can always count on one being noticeably more powerful than the others, and one will be less, and 8 will actually be close to the same.
Now I don't build engines for a living, so I cannot attest to that. But I can tell you that of all the five stock engines I have ever had, over 54 years now, that is probably close to true.
So, Just cuz your buddy runs 20* of idle timing on what you might think is an identical engine to yours, does Not mean yours will like it. Engines are like women; some are high maintenance, some low, and the rest well, you get it. Ok enough of that crap.
Back to ignition timing;
For most of us, well maybe just me IDK, the number one timing deal is to pick a Power-Timing number that you know will NOT WOT-detonate at some reasonably low rpm number, like 3400, and stick to it.
Then
from your known convertor stall rpm, figure out how much timing your engine will tolerate there, by experimentation, and write it down
Then
work out your Idle timing by first setting the Transfer-slot exposure required to eliminate the tip-in sag that, when it happens, is guaranteed to aggravate the crap out of you. and Second set the Idle rpm with timing, to as low as might be required to not bang into gear, but just high enough to not stall when you put her into gear.
Thus you have three known to be accurate timings, and all you gotta do is connect the dots by modifying your distributor. If that is beyond your capabilities, just send it out to somebody with a distributor machine, and presto! when it comes back, you are done ........ at least as to power timing. This leaves you, with the comparatively easy job of setting up your VA.
now, here is something you need to know;
If your Idle-Timing is TOO RETARDED, the fuel mixture in the combustion chamber will take longer to finish burning. This will then heat up the cylinder walls, which heat the cooling system will then have to deal with. That heat should have been used to propel the vehicle. any extra, should have been sent out the into the exhaust, but NOT while it is still burning. So then, Idle timing needs to be as high as is possible, yet not higher than might upset the first two parameters of T-Port- sync and banging into gear. There is a fly in this ointment which is cylinder pressure. If your pressure is very low, then heat of compression will be low, and the engine will naturally run cooler, at idle. But as the pressure rises, which it has to, make power later in the rpm band, the engine will make more heat even at idle. So then, your cooling system has to be able to deal with that, and
as you have found out, your way sucks. Not many guys will run an electric fan, on the street, in the heat of the summer, especially not as inefficiently as yours is set-up. Hey, I'm not attacking you personally, maybe/probably, you didn't know. As others have pointed out, you got some work to do, to bring your system up to speed, and forever after you will be monitoring your sloooow to respond temp gauge. While ypu got one eye on the gauge all the time, who, I say WHO, is driving distracted?
IMO,
Do yourself a favor and just switch to the tried and true direct-drive mechanical fan, inside a shroud, behind a sealed to the core-support, rad. Align your pulleys, tighten the New belt, and just go drive.
After you see how wonderful it is to cruise worry-free, THEN you can start reducing efficiency, on purpose, to some compromised level, that maybe gets you seven more hp at 5000rpm, which rpm you almost never go to, and if you do, it's like for two seconds at the top of First gear. Whereas the vast majority of the engines life will be spent at less than about 3500, so I mean, that low rpm cooling, is or should be, top priority.
Yeah I know, people tell me I'm too abrasive; and for that, I'm sorry. Listen; I'm old, old people get that way. Now;
go buy a used big 7-blade all steel factory A/C fan, off a 70s Dart, and install it on a new Ford pick-up Thermostatic clutch, and push that rad into the core support, and I don't care how retarded you idle that engine, your overheating days will be history .
