Not common knowledge at all. Tube diameter is only one part of radiator design. Just like number of cores is only one part. If the tubes get too large, they don't efficiently transfer heat across the entire cross section of the tube. Under laminar flow the water "in the middle" isn't contacting the walls of the tube, which is where the heat exchange takes place. But too many cores can be an issue, since the air moving through the radiator is warming as it goes from front to back. The last core sees warmer air, so it can transfer less out.
Without actual data though you can't say a 2 core 1.25" tube radiator cools better than a 3 core .75" tube radiator. Depends on the water flow numbers, air flow numbers, surface area, number of fins, etc. etc.
So no, just because you spent a **** load on a 2 core radiator with big tubes does not mean it actually cools better. The whole "bigger tubes cool better" trope is just an advertising gimmick, without the data it doesn't mean anything.
Lol. Manual switching an electric fan is the dumbest way to do it. That's race car only BS. Most thermal switches only activate at one temperature, which makes them a poor choice for a two speed fan. The biggest efficiency gain from having an electric fan is only running it when it needs to be run, and optimizing the temperature range so it matches where your engine makes power. The best way to do that is a fan controller. And yeah, all modern cars use a fan controller and pretty much all of them will go 100k miles or more without an issue.
But let's get real, you have a car that spends 99.9% of it's time in the garage or on a trailer. A 2,000 CFM SPAL wouldn't keep my car cool even with half as much horspower as you have, which means you
never drive your car under anything even close to resembling the conditions I drive in. Which makes your set up pretty much useless for anyone that actually
DRIVES. Like I said before, out of this entire thread you have the least capable cooling system.
I mean, you admit this much, which means you probably drive even less than this. So let's see what your car does and doesn't do...
Ok, won't go 75 on the freeway...
Gets trailered to the track
Never goes more than 50 miles one way
130 miles round trip? Nope.
So there you have it folks, if you never go faster than 75, never drive more than 50 miles one way, and trailer everywhere you go then
@'68cuda416 has a really expensive, less efficient cooling system to sell you on.