So now that I have aluminum heads, intake and valve covers and soon radiator, do I need to worry about corrosion of the internal parts?
I saw an add for a radiator cap with a built in anode.
Is this really necessary?

 

No, you don't need anything like that- that's just misapplied science designed to drain your wallet.

Standard antifreeze/coolant contains all the corrosion inhibitors you'll ever need.

 

I was pretty good at the upkeep and fluid needs of my '80 when it was on the road but after a while it developed a coolant leak at the intake manifold on the passenger side very rear most part of the surface where it contacts the cylinder head, I found this after I diddled around a bit wondering where the coolant was going cause it never left any wet spots when parked, went thru the ritual of thermostats etc. and noticed the opening that the thermostat sits in (under the outlet) was very corroded and when I finally took the intake off to re-gasket it so was the manifold at the location of the leak , so you may beleive what you want but I think when dis-similar metals are in contact you will have some sort of negative reaction, so for what ever they charge for one of the sacrificial anodes might be worth the price to you , so far its worked for me, Good Luck, Peace,,, Moosie

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'80 L-82, Presently in the process of taking the '80 apart cause it's a rust bucket, And putting the drivetrain and interior into an 82 that I bought. With a changeover to a 4 speed while I'm at it. Other interests My son and daughter. Our '40 Ford Deluxe tudor sedan (stock for now) and our favorite,,,, ole Blackie, our '78 Harley Davidson Low Rider (FXS), the "REAL" freedom machine!
Ever wonder what the speed of lightning would be if it didn't
zigzag?

 

i don't think alu rads last as long as copper.
But, heads & intake are so thick, they should be ok.
Did u see those alu rads by Dillon for $139? very tempting! At that price, who ares if they rot out in 8-10 yrs? Google chevy racing radiator

 

There's millions of cars around the world that have a mix of aluminum, iron, s/steel, brass, copper and plastic parts in their engines. There's no known widespread issue with corrosion.

There's lots of C2/C3 Corvettes that still have their original aluminum intakes, rads or expansion tanks. No leaks.

 

I change my coolant every spring, cost me about $15.00 to do so, cheap peace of mind. Most people forget to use distilled water in their system. Tap water will leave deposits that may look like corrosion, this is just my view.
I have never had an issue with any aluminum engine parts.