2 baits, sir that makes you a master! Ha Ha. I do remember you asked this question earlier. And yes they did with the 4.6 liter. I couldn't find what year, what model. Cast iron actually does have its plusses. I just got through reading a comparison on 350 small block Chevy heads. Iron vs aluminum. After flow testing, Dyno testing, etc etc, they came up a tie. They did say that with different cooling jackets, their might be a difference, but these weren't stock heads. They both had same cc rating, used same 91 octane fuel. In some situations the extra heat from cast iron is actually favorable. Years back a friend that worked with me, took his stock 400 Cid Pontiac Firebird and pulled the heavy cast iron heads, and spent close to $1,000.00 to have them ported, and 3 angle valve job. That vehicle was an absolute beast right off idle. Stayed cool, only drawback, was I helped him reinstall heads. Man, they weighed a ton. My back hurt for 2 days after. So yeah, unless you live in hot climate, or drag race at 8 grand, run after run, cast iron works fine. Did for GM, and Ford back in the day.
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