Would you choose a chrome four blade mechanical fan or a Six Blade plastic Fan to cool a very mild 302 Neither fan will have a shroud
My first choice would be the Taurus electric fan upgrade, but if I had to choose between the 2 fans shown, I would use the metal one and toss the plastic one in the garbage.
That’s what I thought. Why is the plastic one junk? I have never used one before so I am uneducated.
I don't believe either will keep the engine cool w/o a shroud. Warm/hot days, slow traffic, long train delays equal rising engine temps. A open fan is also dangerous; accidentely get a limb across a blade -- goodbye to that limb.
If those are your only choices then stick with metal, I would be afraid to open hood with the plastic fan turning, but like others have said shroud is needed
But keep in mind that the more blades it has, the more power it takes to rotate it. Electric is the way to go here in my opinion.
I had one of those fiberglass fans fly apart on me many moons ago. Sliced right through the upper radiator hose. Then ran a six blade aftermarket metal fan that worked ok. Neither compares to the Taurus electric fan I picked up on Craigslist for $30.
Using a shroud just makes sense. It channels the air to make cooling more efficient. I was concerned that the aluminum 3 row rad I bought for my Mav wouldn't allow me to reuse the original shroud but it did and pretty nicely at that. And A metal bladed fan always beats plastic. More rigid and moves air better. Electric is the way to go but if you want to stay original, go with a metal fan.