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Re: New Flathead Blocks and engines

To: websters@pyramid.net (Dan Webster), land-speed@autox.team.net,
Subject: Re: New Flathead Blocks and engines
From: ardunbill@webtv.net
Date: Sat, 2 Dec 2000 10:52:46 -0500 (EST)
Many thanks to Dan Webster for telling the contents of the R & C article
on the French Flatheads, especially since when I went to get it, the
Dec. issue was gone off the newstand already.

I'm glad to see so much interest in this subject on the List.  Couple
items caught my eye.  The block material is given as "cast steel".  Can
we kick that term around a bit?  In brief, my Machinery's Handbook 23rd
Ed. says cast steel is made in many compositions in carbon and alloy
steel ranging in tensile strength from 60 to 200K lbs. psi.  So the raw
term "cast steel" in the article does not tell us much.  Plus, French
engineering may have a different sense or understanding of the term,
plus, the journalist at R & C, or anybody else, may have mis-heard what
somebody said, etc.

However, I suppose what we are to take from the item is that these
blocks are "stronger" than our domestic Flathead blocks.

But are they?  I have a reprint of an original Ford Service Bulletin
dated Dec. 29, 1939, which states under cylinder block material, "Ford
cast alloy iron".  The Handbook cited above gives "cast alloy iron" as
iron castings incorporating alloys such as nickle, chromium, molybdenum,
etc, with tensile strengths ranging up to 70K or more.  Way stronger
than the basic gray iron castings whose tensile is only in the 20-35K
range. 

If the French Flathead blocks have more meat around the main bearing
bosses, the center in particular, it would represent an improvement. But
don't forget that Ardun Doug, and others, make center main girdles that
reinforce this area, for those that want the insurance. And, don't
forget that C.T. Automotive, Lattin-Gillette and "The Hayseed" have many
Bonneville fuel and gas records, over the last 50 years, Long Course and
all, with steel center main caps yes, but girdles, no.  Not to mention
many other Flathead/Ardun teams.  

While I'm at the documentation, let me mention that the same Ford
Service Bulletin gives the crankshaft and camshaft material (both the
same) as 1932-34: "Forged Steel", and 1935-40: "Special Ford Cast Alloy
Steel" (I daresay the same spec applied clear up to 1953).  We don't
know exactly what Special Ford Cast Alloy Steel was, but in general it
was undoubtedly within Machinery's Handbook's definition, and certainly
has been proven by time in many millions of production vehicles, and
many Bonneville records, to be dern good.

The other eye-catcher was that the French blocks are redesigned to stop
the center stud holes cracking to the water holes.  I have four good
blocks that passed magnaflux and are ready to use for racing.  Of the
four, one has one of these cracks on each deck.  But the said cracks are
considered incosequential and harmless.  The studs don't pull out, the
tapped hole doesn't crack on the other side, it doesn't cause a water
leak.  Speculative legend has it that these cracks occur when people
have a boiling engine, and dump cold water in the radiator to cool it
off fast.  In other words, abuse that should never happen.  

Except for the documentation, the above are merely the thoughts of an
enthusiast, so I hope some people who really are qualified
engineers(with or without degrees) will contribute further to the
discussion of the pros and cons of the new French Flatheads.  Cheers
from Ardun Bill in the Great Dismal Swamp, Chesapeake, VA 

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