Seems like nowadays everyone is using aluminum heads more than cast iron. I understand that the newer style with today's advancements in technology flow better out the box, weight savings etc. but does anyone prefer the old cast over aluminum? Doesn't cast take a beating better and are more forgiving when over heating.
Cast Irons just take more to make flow as a new "cast as designed for flow" Aluminum set. Irons are my preferred go to on the street after porting for flow. The other part is the expansion qualities are more similar in Iron Heads with an Iron Block, less gasket problems typically. But it's pretty easy to just bolt on a set of new Aluminums and be on your way.
Plus aluminum has the added effect of being better at heat transfer, thus you can run a higher CR on pump gas. My Olds is 11:1 with no pre-combustion pings or knocks, try that with 92 octane gas and cast iron heads. Cast iron is fine, looks more HAMB friendly, cheaper (maybe), and produce more than enough HP to go around. But...
I'm waiting on the machine shop to get back with me on a price to re-do a pair of cast iron SBF heads. Told them I wanted them ported, new valves, springs and rockers. Online videos and at the car shows aluminum seems to be the go to nowadays...
Not to mention cost. IF you pick up or have a pair of cast heads that need complete rebuild by the time you pay a shop to install valve guides, new valves, machine seats etc you will almost spend as much or more as a new set of heads and still have the cons of cast heads mentioned above... ...
Kinda depends on the car, and what you want to do with it. Sometimes aluminum is the way to go, other times iron is the way to go. For example, I had to put factory early aluminum heads on Plan II, but I have to use old iron heads on my old truck.
I like to spread the $$$ around. My 327 has NOS cast iron 2.02 heads. My 350 had cast iron heads when I first built it but replaced them with Edelbrock aluminum versions. My aluminum 427 Rodeck small block has AFR aluminum heads. My 2000 Silverado has oem aluminum heads as does my 96 Impala SS.
I think there are a few things to consider: Know the sourcing of what you are buying. There are both very good and very bad castings being sold in both iron and aluminum. Static compression gets talked about alot, but dynamic compression is perhaps more important and can be influenced by cam selection. Aluminum heads are very repairable. If you damage them they almost always can be welded and machined back to useable. As to cylinder port flow, be honest with yourself. Once you get beyond bench racing, how much flow do you really need for a street driven hot rod? Will you even get up to the RPM where it becomes part of the conversation? Bottom line both iron and aluminum work well. Performance comes down to cubic dollars. How much do you need? And if you spend for it, will you actually get to use it?
Back when Machine shop labor was cheaper I went iron. Make a list of what a used head needs to get back in service,and then expect a surprise somewhere.....You need all new guides...you really should put in hardened seats......seats are too narrow to cut,and suddenly a set of aluminum are in the running .
I still use cast iron heads even for performance stuff. My SBC has a set of World Products Sporstman II’s that it has had since probably 1994 or so.
On my bb mopars all I have is iron heads that were initially worked back in the 80s and early 90s when aftermarket heads were limited for the big block Mopar. On the last refresh I replaced all the valves and hardware in the heads plus installed exhaust seats and Touched up the port work. I believe I spent about $1400 in comparison I would have needed to spend $3500+ for new quality aluminum heads and only gained fifty horsepower or so. The Cheap Chinese heads aren’t worth there price when you consider horsepower numbers. Cheap valves and incorrect springs means you should buy good parts for them and do a valve job. If a shit pot full of free money fell in my lap I might drop the bucks for TrickFlows or Indy heads but I can’t believe I would even feel the difference on the street. Before I called it done I dynoed my last refresh and produced 650hp and 620tq. One thing you don’t hear from the guys saying automatically put aluminum heads on it is that iron heads all things equal will produce more power because the heat stays in the combustion chamber. There’s one more reason why I don’t mind using the iron heads well maybe two. The first one is like doing the port work , they get a little bit better each time they are off for a refresh and the second is I like hearing all the opinions on how I should just change parts with aluminum but I like thinking the difference between mine and there’s is mine was built and there’s was assembled.
I agree with Bandit Billy. Many years ago a friend wanted to sell a new in a crate CE 327 11:25 short block. At the time I picked it up and through the years had the block squared and plate honed. I kept the high compression pistons and my local machine shop had a set of Canfield aluminum heads. Seemed like a great combination for the short block. But I carefully selected the hydraulic roller camshaft that would bleed off based on the overlap. It's all ready to install in my '55 Delray and I expect no issues with detonation. If I'd swapped the pistons for flattops I'd probably gone with cast iron cylinder heads.
Trick Flow has a set of aluminum SBC heads with no accessory holes and the double hump raised section. Paint them engine colour and they look HAMB friendly.
As for Camel hump heads it might come down to the numbers and if you have a decent set of iron 202 heads to rebuild according to these asking prices. 1600 for a pair of ready to bolt on as cast heads from Summit or 4 or 500 from one of these guys if they don't take what you wave under their noses plus a hefty machine shop bill.
P A W.(remember them!) sold me my Windsor jr. cast iron heads fer my SBF. They were less expensive.....safer if/when the old Ford gets hot.... look just like the FoMoCo heads I pulled off... flow wayy better than the stockers... I don't hafta be so particular when pulling the plugs when hot...came with cool stickers ! What's not to love ?!! 6sally6
I didn't realize you had a set. I'm assuming that's the engine that isn't currently in your car? How did you like them? I had a valve job done on a set of iron heads 2 years ago. The only parts I had to buy were new valve springs and seals. The prices of a brand new set of aluminum heads are mighty attractive.
I couldn’t imagine the weight of a fully ready to install 426 Hemi head. Just for that reason alone I’d swap over to aluminum.
Saw an unexpected advantage of aluminum heads twenty years ago when I was helping at a shop that the owner was happy to teach me stuff at(even threw in cool parts and tools in return for work I did). Guy that is now the sheriff there was a teenage street racer then and had a pickup with a 350 that had a lot of parts thrown at it. Aftermarket rods, forged pistons, complete Edelbrock top end including Edelbrock aluminum heads, ceramic coated headers etc etc. He brought it to the shop because it had a slap noise he couldn't figure out. After teardown it turned out that one of the rod bolts was slowly backing out resulting in the piston hitting the head. We ended up going through it and building a 383 stroker. All we did to the heads was replace the valves. Little to no noticable damage to the heads itself. Meanwhile the guy went on bragging about having built the engine in shop class(and not me and my alcoholic Cajun buddy lol) and going to way too big a carb lol. But long story short I imagine if they'd been iron heads they likely would have cracked
TRW also supplied Ford with forged pistons for the HO 5.0L buttstangs from '87-???..'92 ... I have 2 5.0s with those pistons in them....
Find some guy going with a new set of aluminum heads and buy his old heads for cheap. Best scenario is he had them updated and tricked out when he built the engine and only averaged a few thousand miles a year.
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