Yesterday I scored a set of Fenton heads at a yard sale for $250. I hear a lot of mixed opinions about the brand, and realize they’re not the quality of some other brand. However, for that money I couldn’t resist. These heads will go on an internally stock EAB with dual 97s and headers. The project is The McKindley Hot Rod. https://www.jalopyjournal.com/forum...hot-rod-re-build.1324681/page-2#post-15589722 The heads are in amazing condition. No broken fins, no corrosion or scale in the water passages and checked with a straight edge they are perfectly flat. One question: does anyone know the compression ratio of these heads? Attached are a few pictures as found.
I only took the heads and paid $250 for them. Guys were lined up to buy the heads and the intake manifold. The intake had a large welded repair, and it was for a 59AB. Another guy bought it for $50. I felt lucky to get the heads. The seller said she had about 50 messages about the parts.
I wouldn't place too much credibility on an internet post giving the compression ratio on a set of 60+ year old used heads. You're better off figuring it out for yourself. Get the swept volume from the bore and stroke, use a cheap burette to determine the volume of the chamber, subtract the volume of the piston dome, do a little high school math, and you've got it. Anyone wanting to get the best performance (both "go-fast" and fuel economy) should concentrate primarily on obtaining the optimum quench between the piston head and combustion chamber of around .050". There are several threads, both here and on the "Ford Barn" explaining how to do that. I have found that if you get the quench correct, the compression ratio will follow. Back in those days, almost everyone advertised their heads at 8.5:1. Given the variables involved, it was just a guess.
You can tell from the photos that those heads have been cut. Definitely check your clearances before hitting the key. I have two sets of Fenton heads for 59A’s, but have never run them yet. Both my sets are really nice shape. Either says they were crap from the beginning and didn’t get used much, or were great quality and stood the test of time.
I have been running a set of original Fenton cast iron headers on my '51 since 1987 with no problems. An engine replacement in 2016 showed the entire exhaust system to be in excellent shape. I can't see a company that manufactured products of this quality to have produced an inferior product.
Last year I pulled apart a Flathead that had been knocking like crazy. I found that the “pair” of beautiful Edlebrock heads was not a “pair” at all. Both had been cut but not the same (I suspect that a previous owner had bought the two heads separately and did not bother to check them out before installing them). They didn’t look right to me so I CC’d them. One head was cut to produce around 9.5:1 (too high for a street flathead), the other head however was more like 10.5or 11:1 (totally unusable). These were on a 272 CI Merc motor so the CR was already much higher than they would have been on the 239 motor that they were designed for. It is pretty easy to CC (I counted how many drops it took to fill them and then I put the same number of drops in a measuring cup to find the actual volume) and you can find the resulting compression ratios by googling it or posting the figures here.
And how are the threads on the spark plug holes? I am always amazed how people can't get a plug thread started right. Especially in aluminum. They will cross thread them to start, then crank the shit out of them, thinking they can't be wrong. Until the thread is ruined.
With a little bit of work such as doming them for piston clearance they should be fine. Don't know about mixed opinions about the brand. Its been my experience Fenton's were as good if not better than a number of other brands including the two most popular Offy and Edelbrock. I would take a set of Fenton's any day over many others another bonus that lower full length fin is killer. Ronnieroadster
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