"Cheater Heads"

Which is why I asked if the above claim has been proven, specifically on a flat head. I've heard PLENTY of claims (lore) regarding small block chevys that iron heads retain more heat and make more power (for the same compression) -just exactly like what was stated above. The test in the article proves otherwise.

How that article relates to flat head Fords, is that they are both internal combustion, V8 engines that operate on the same fundamental principles and physics. So, I'd ask again; has someone documented the above test on a FH Ford that proves the opposite of what my article shows?
 
The thermodynamics cut in both directions... aluminum allows more compression without pinging because it cools things down faster, but the cooling of course moves power from the power stroke into the water jacket...
Yunick discussed all of this at great length in many ways...he once suggested that perfect heads for racing would be structurally aluminum but with iron chambers to keep the heat working for a living! He also kept after the aluminum he worked with: coatings on pistons to lower heat transfer through the top (this could be taken only so far before piston melted through) and aluminum heads in NASCAR engines repeatedly sloshed internally (with sodium silicate/water glass) to cut heat transfer. Note that he presumably kept away from spark ping through turbulence and surface detail...?
I'm not sure how you would go about fully thrashing this out on a flathead...what heads are available with identical chambers in iron and aluminum? Then...I guess you would have to mill and modify both until you reached highest possible compression without ping and see whether the presumably different compressions gave the advantage to better heat transfer or higher total comp.
And of course you can't make otherwise identical FH heads differ in compression without also making transfer areas different, affecting both flow and the resulting different dynamic compression.
 
And...the car Craft test ran identical CR'S, demonstrating some muddle. Obviously neither head was at any sort of thermal limit for controlled combustion...usually the discussion is of whether there will be a difference when both types reach their limit for proper combustion at probably different CR's.
 
Tom400CFI said:
How that article relates to flat head Fords, is that they are both internal combustion, V8 engines that operate on the same fundamental principles and physics. So, I'd ask again; has someone documented the above test on a FH Ford that proves the opposite of what my article shows?
Click to expand...
Maybe they both operate on the same fundamental principles, one is an OHV engine and has different dynamics.
Even if there were a similar test done on a flathead, I doubt that there would be any 'seat of the pants' difference that you would notice.
 
Put a seat of the alum heads in a back pack and run around a 3/8 mile track then take the same backpack and put a set of iron heads in it and run the same distance, you will find out why alum is better! From my old mentor back in the 60s.
 
I always look at these types of articles and my first thought is. "Yeah, but would you notice it on the street?"

--louis
 
This brings me to the question, what did Ford think of when considering
aluminum heads. My early 36 doesn't have aluminum heads. When did Ford
start using them and when were they no longer used in the old flatheads?
At some point the disadvantages must have overruled the advantages at least
in the passenger cars. Did the early early half ton trucks have aluminum
heads off the assembly lines in some years?
 
terry said:
This brings me to the question, what did Ford think of when considering
aluminum heads. My early 36 doesn't have aluminum heads. When did Ford
start using them and when were they no longer used in the old flatheads?
At some point the disadvantages must have overruled the advantages at least
in the passenger cars. Did the early early half ton trucks have aluminum
heads off the assembly lines in some years?
Click to expand...
The '36 that I purchased back in the early 50's had aluminum heads on it when I got it. They were changed to iron heads because the aluminum had erosion on the seal surfaces (too much for gaskets to seal)
Erosion, one dis-advantage.
 
34PKUP said:
Maybe they both operate on the same fundamental principles, one is an OHV engine and has different dynamics.
Even if there were a similar test done on a flathead, I doubt that there would be any 'seat of the pants' difference that you would notice.
Click to expand...

I am aware of the differences. However the laws of thermodynamics don't change. Anyway, I posted the article, b/c for YEARS, I've heard the same BS claims on the 'Vette Forums (I have a 'Vette).

"Iron heads retain heat and therefore, make more power."

^This is regarding SBC's. People say it b/c they heard it some where, and they simply regurgitate it. I never saw anyone actually TEST that claim, until I saw the article that I posted. Holy shnikies...the "myth", wasn't true after all! At least not on SBC's, and likely not on SBF's, Chryslers, Hondas, and probably not even on FH Fords.

Compression is the holy grail for tq and that is the benefit to aluminum; that it allows you to run higher compression. Do the Ford aluminum heads actually give higher compression? I have no idea, but if they don't then there is no benefit to them other than weight and looks.
 
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Now that's the best artical I've ever read that addressed this myth. I've often wondered if it was true and what the difference would be. I doubt very much it would be noticable on the street and only Bonneville might prove it one way or another. It reminds me of JWL"s book: In the beginning he tested a stock 239 engine changing only bolton changes and he proved one thing, The Ford engineere had did their homework very well and there was very little you could do to the engine that would improve torque in its designed operating speed and load. The big kicker was the comparison of dual exhaust against the stock exhaust. I'll let you read the book for that one. Modifying to operate beyond its design perrrameters is a different story and maybe cast iron would be better at the limit of power output, but we'll never know, unless John want's to add another chapter to his book. What say John??
 
The question was about "Cheater Heads".
"Cheater Heads" are the heads, put out by Ford, for the higher elevation areas, like Denver, Colorado. Stock car drivers used to run them on their stock cars, because they looked, exactly like a stock head, but had higher compression.
The chances were low that they would be challenged for running high compression heads, when they had these genuine Ford script iron heads on their engines.
Today, they are very rare and command a nice price.
MIKE :)
 
When I was a kid exploring an uncle's shed I saw several early flathead aluminum heads. He explained that they had corroded and leaked water badly-no permanent anti-freeze back then and everybody ran plain water in the summer; hard water from the well, no less. So aluminum heads were shot in no time. I do remember reading that aluminum heads were a little higher compression.
 
40 Deluxe said:
When I was a kid exploring an uncle's shed I saw several early flathead aluminum heads. He explained that they had corroded and leaked water badly-no permanent anti-freeze back then and everybody ran plain water in the summer; hard water from the well, no less. So aluminum heads were shot in no time. I do remember reading that aluminum heads were a little higher compression.
Click to expand...

40 Deluxe ....................
Actually, the aluminum heads were a lower compression than the cast iron ones. I don't have the data handy, but perhaps, someone can fill that in.
MIKE :)
 
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