Puller electric fan with 4 core radiator?

Bewy said
Exactly right. By the time you get to the 3rd & 4th row of tubes, they add little to the cooling ability of the radiator.
Best solution is clutch fan. There is a myth that elec fans do not cost power. They do cost some power & the amount will vary with the fan motor rating. A higher rated alt is also likely to be reqd.

3 rows still work well, again, mine works great and it's just a cheap Champion 3 row. There are definitely better radiators out there, and yet it's still more than enough for my 400+ hp, .060" over 340 with iron heads. The factory ran both 2 and 3 core radiators, and both had smaller tubes than what is common now. But that goes back to my original point, there's a lot more to a radiator than just the size of the tubes or the number of rows.

And of course electric fans still cost power, we're not talking about violating the primary laws of thermodynamics here. But unlike a straight mechanical fan, they only cost power when they're running. Even with a clutch you're only controlling the fan somewhat, either by RPM (which isn't necessarily best) or by vague thermostatic switching, which is no where near as precise as a good electric fan controller. Even if a larger alternator is required, the additional parasitic loss is pretty much only when the electrical load is increased (ie, when the fans are running). When they're off, the load isn't significantly different than a lower rated alternator. The savings in parasitic loss is primarily from better control, and clutch fans are still far less precise than an even half decent fan controller. And that's before we even address being able to better manage the engine temperature, which in and of itself can mean more power.

forphorty said
Well, let me state the obvious. An elec fan doesn't cost power when it not on.

Exactly.