Cylinder head

I have read several comparisons between the new vortex head design and the Edmund cylinder head design and Jack Clifford cylinder head.

In my opinion, both of these fellas were trying to place the spark plugs over the piston. Unlike the stock head where the spark plug is over the exhaust valve.

I will never say either Mr Clifford or Mr Edmond did it wrong in what they were trying to improve on the Hudson flathead engine. Back then, the vortex design wasn't even though about.

It's like the hemi cylinder head design. It was originally designed for the B29 bomber engine. It wasn't applied to a car engine until the early 50's.

Again, please show some respect to the men that were trying to improve on the flathead performance. Before the overhead valve engines finally figured out how produce the horse power we all know about today.

I'm enjoying building my first flathead engine. This includes having built a GM HEI distributor for my engine.

Cheers to all flathead performance engine fans.



  • 50C8DAN50C8DAN Posts: 2,790Senior Contributor
    Wookie, you can review the presentation I gave at the Nationals in Ypsilanti to get a better idea of the evolution of the flat cylinder head design.  I did a lot of research to put it together.

    The first major chamber improvement was the Ricardo combustion chamber that Ford introduced in 1932.  This design was quickly adopted by virtually every other manufacturer of the day.  The basics of this design were used even by OHV engine makers into the 1990s.  All Edmunds heads used the Ricardo design, which also included putting the spark plug over the exhaust valve.  Some notable exceptions were the Harley Davidson flathead used in the 50s until its end in the late 60s and actually, Hudson's combustion chamber used a more heart-shaped design.  The Twin Vortex design is a take-off of Ed Winfield's Red Head he came out with in the late 1930s.  Winfield patented his design and in flathead racing circles it is called the "crows foot" due to its odd forked shape.  The original Red Heads are often sought after in the Ford Flathead world.  This design was copied by Weiand and other aftermarket manufacturers after the patents expired in the 1950s, but by that time the days of the flathead were pretty much at an end.

    There are two reasons for the spark plug placement over the exhaust valve: 1) The top of the center top of the head is basically flat and putting a spark plug there would end up colliding with the piston unless you recessed the plug up into the head - not a good idea.  2) the quality of the gas of the day was relatively poor and precombustion in hot areas was a problem and the exhaust valve area was about the best location to prevent that problem.  When I talked to Chuck Fellows about why they put it in the center he said that with the vortex shape the plug does not have an interference issue with the piston and that it is better for flame travel.  Chuck and Rudy also looked at many other "improved" flathead designs to come up with theirs, and when I followed that trail I found that in 1954 Packard moved their sparkplug location from the exhaust valve area more towards the center of the combustion chamber.  I found this interesting since it was in the dying days of the I8.  

    What I also found surprising is that if you compare the Edmunds and Clifford heads combustion chambers they are identical.  I don't mean similar they are the same exact shape.  If you look at Jack Clifford's last catalog which he put out for years (with some price changes, but no content change) he says his head had "an all-new combustion chamber design".  I now find that pretty much marketing hype as Edmunds's heads were rarely used by anyone I have talked to for serious performance applications.  They are however great eye candy!

    I am not taking anything away from anyone's efforts.  However, I am a newbie when it comes to the combustion chamber stuff.  I only dug into it due to the effort to bring back Chuck's and Rudy's design and after doing the research I am a lot more informed on what came before and where it ended up.  Of course, at this point, all of this is just for fun. It will make little difference to 98% of the Hudson owners out there what the shape of the combustion chamber is since the day of the flathead is long gone and what we are doing is pushing an envelope for those in a little corner of the Twilight Zone!
  • super651super651 Posts: 574Senior Contributor
    Dan, Thanks so much for bringing some History  about cyl heads and combustion Chamber stuff for all of us Hudson  Automobile  owners it was well put together
    and very understanding.       Hudsonly   Rudy Bennett
  • Smonica46Smonica46 Posts: 22Member
    Great review Dan. Thanks for putting it together ! Dave.
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