340 Overheat / Radiator Geyser
On one of those trips, if you shoot the rad imput/output temps when hot, and we know the new rad is doing its job of shedding 50*ish, then we can eliminate that and try other stuff.
My rad is not that good.
But it does maintain a spread of 30/35 degrees, which is enough in my system, because the Thermostatically-clutched fan is able to keep the high limit to 207.
The stat is a 195*, so it's like
@mitch340Duster says; the temp scoots up in a hurry. But the fan catches it almost right away. In summer, the stat opens within the first mile. But I'll have to drive about two more before the aluminum heads are warm.
How do I know that?
Actually, I don't. But tell me if you agree.
Immediately after I get up to speed, I set the cruise by throttle-stop, to 62mph. A mile later it has climbed to 64; and another mile to 65/66, where it stays. Cruising rpm is 2240@65mph in GVod.
Oil in the A833 is 50/50 dextron-II/ 85-90 dyno EP.
Oil in 3.55 diff, IIRC is 85/115 dyno.
So I realize that "some" of the speed-increase is/may be, in the fluids coming up to temp. But, if you can come up with an alternate valid reason for the nearly 5% increase in cruising speed, with no change in timing, nor in throttle-opening, I'll try to be open to it. lol.
The point is that even a marginal rad can work, if the rest of the system is functioning properly.
So then, what is my definition of a good system, minus the rad?
IDK.
I can only tell you what works in my car.
>8-blade Hi-Flow pump which has the anti-cavitation plate on it.
I run mine slightly Underdriven, cuz I like to whack the throttle up to 7200 in first gear, which thru dual 3" exhaust and turn-downs, from the cab, is sortof visceral.
>Matching Hi-Flow stat which opens wide.
>A large diameter all-steel Seven-blade , direct drive fan, in a shroud.
>My hoses are molded, and the supply-hose was already ancient when I installed it in 1999. The lower has the anti-collapse spring in it. And I run a 7psi cap
> the bypass hose has a big restriction in it, so my in-cab-heater is the bypass.
>100% water is the best coolant, But once the system has been de-bugged, I reverted to the standard 50% glycol.
> Additionally, I run a 7qt roadrace oilpan with 5>6 qtsUS in it. and
> Fresh cold above the hood air, into the 750DP mounted on an AirGap intake.
>> The rad is out of a 74ish Dart 318/auto with A/C. Even the patches on it have patches. and it is mounted in the original unmodified slanty core support. IIRC it is a 26"rad in a 19" opening.
> My engine, by it's trapspeed (92mph@3450 pounds) in the Eighth is making 430 hp. It will idle all day any day at 700rpm@12>14 Advance, and will pull itself thru any car show at 500/550 rpm with just 5* advance, with the 10.97 starter gear..
The point is this;
IMO,
the rad is not nearly as important as many street-people think it is. It is just one piece among the many, on the list that makes up a system.
After the system was known to be adequate, I installed the Thermostatically controlled fan clutch.