Flathead chamber design

[Nikolas Ojala]

By the way, is that referred Kenny the record breaking Ken Makuch?

I refer to this news article:

David Pevear: Westford man's roadster sets record at storied Salt Flats in Utah Lowell Sun Online, 27 August 2012.

[bill jones]

-that story is about a different guy.

-Kenny Kloth lives in SLC Utah area and his race car is this 1949 Mercury sedan--that has ran 150MPH twice---might still have the XF/pro record at 140.551 that we set in 1991 with a single four barrel carburetor

-we had also gotten the XF/galt record up to 147.020 in 1998 right about the same time we ran the two 150mph runs--but we couldn't get two 150's back to back for a 150 record.

-same exact car and engine in both classes----just had more experience and a totally different intake manifold with mechanical fuel injection in 1998.

'49 Mercury & Kenny.jpg

[Nikolas Ojala]

-that story is about a different guy.

-Kenny Kloth lives in SLC Utah area and his race car is this 1949 Mercury sedan--that has ran 150MPH twice---might still have the XF/pro record at 140.551 that we set in 1991 with a single four barrel carburetor

Ok, thanks!

I found an interesting discussion on The Ford Barn:

• Boring a flathead The Ford Barn, August 2010.

[Nikolas Ojala]

Please correct me if I'm wrong!

The real bottlenecks in the flathead are ports and valves, while the chamber shape above the piston is usually less important potential bottleneck.

Did I get it right?

[Nikolas Ojala]

It seems that at Belgian D-motor they did not bother to optimize the pistons any way. I just watched some drawings of LF26. The pistons seem to be simple flat tops.

D-motor_LF26_inside.jpg

[MichaelThompson]

Here is a good cross sectional illustration of a Ford Flathead V8.

Now by simply looking at it one would have a very hard time believing that "high doming" the area over the piston would not help the flow capabilities of this engine.

Filling this area with a corresponding piston that fits the dome tightly and tapers to the top of the cylinder all the away around the margin in my mind would regain and maybe exceed possible compression ratios of a more conventional design.

That is exactly how a Chrysler Hemi works albeit being fed from the top rather than the side.

When I spoke to Mr. Navarro the hi dome was still a winner in his mind. Now maybe he found something that was wrong later on. I don't know but he ran those things from the '40's to the 90's and still believed in their merit.

[PackardV8]

Now by simply looking at it one would have a very hard time believing that "high doming" the area over the piston would not help the flow capabilities of this engine.

Filling this area with a corresponding piston that fits the dome tightly and tapers to the top of the cylinder all the away around the margin in my mind would regain and maybe exceed possible compression ratios of a more conventional design.

That is exactly how a Chrysler Hemi works albeit being fed from the top rather than the side.

When I spoke to Mr. Navarro the hi dome was still a winner in his mind.

For the same reason there have been few flatheads and hemis designed recently. Both designs are always caught in a tradeoff of breathing versus combustion chamber design. Using the high dome piston results in huge surface area and squish going the wrong way, away from the spark plug. Here's what current thinking high compression pistons look like.

Of course, a flathead has to work within what is possible, rather than what is perfect. Navarro may not have been wrong, but most other flatheads (and I've seen inside many designs over the past fifty years) chose flat top pistons and keeping the head flat over most of the piston area.

FWIW, one of the most efficient normally aspirated flathead Ford V8s I ever saw run at Bonneville claimed to be running 6:1 compression. Breathing was more important to his thinking than compression.
Here's a "Lion" A/B head
which shows some current flathead thinking.

[Nikolas Ojala]

Using the high dome piston results in huge surface area and squish going the wrong way, away from the spark plug.

That reminds me of the turbulence grooves invented by Somender Singh. Those grooves were pointed towards the spark plug. There were some reports that the grooves extended torque towards small engine speed. That was an useless achievement for anyone who wanted to increase maximum power. Perhaps it could be used for improved fuel economy then – maybe – but big industry does not produce flatheads anymore, so the idea was ditched.

BTW these flathead pictures and the test report are not from the same source.

grooves_1.jpg

grooves_4.jpg

ARAI_Test_Report.png

[bill jones]

here's a few pictures of Ford flathead chambers.
-this is an Elco chamber

ELCO CHAMBER.jpg

-this is an as cast Kong head--needing every bolt hole---sparkplug holes---and chamber work in the piston area---and all other prep to make it useful---and wanting the chambers to be like the Elco chambers.

Kong bolt hole diameter patterns.jpg

-made this mold of the Elco piston area using 117 degree low melting point lead.

made this mold using 117ºF low melting point metal.jpg

-using 1/2 of the mold to get the profile shape of the dome this shows the a sample test piece and the 1/2 mold section.

HALF A MOLD OF ELCO CHAMBER, INSIDE OF TEST CROWN.jpg

-built this 3" diameter cutter with the blades shaped to fit the chamber curavture

TILTED BLADE SLOT AND SETSCREWS.jpg

-after machining the crown areas---slotted for the 2nd sparkplug---drilled and tapped for the dual sparkplugs---but haven't finished the chambers yet.

[peejay]

WIW, one of the most efficient normally aspirated flathead Ford V8s I ever saw run at Bonneville claimed to be running 6:1 compression. Breathing was more important to his thinking than compression.

This is true for Mazda rotaries as well, and they're another engine hampered by atrocious combustion chamber shape.

More compression gives better part throttle fuel economy at the expense of max power. Street engine ran 9.2-10:1 compression but the highest power engine I've seen (that the builder was willing to share power charts with!) had 8.5:1 compression. And very conservative ignition timing, so a lot of power was in theory left on the table.

At some point you are losing airflow efficiency more than you gain from combustion efficiency, and combustion efficiency is going to be garbage no matter how good you can make it.

[jed]

Bill is this a new project or one from the past??
Also it looks like you had to drill the water cooling passages.
When you get finished do you have any idea how many cc the chambers will be??
I am trying to understand why there is a spark plug in the center of the piston??

[MichaelThompson]

here's a few pictures of Ford flathead chambers.
-this is an Elco chamber
ELCO CHAMBER.jpg

-this is an as cast Kong head--needing every bolt hole---sparkplug holes---and chamber work in the piston area---and all other prep to make it useful---and wanting the chambers to be like the Elco chambers.
Kong bolt hole diameter patterns.jpg

-made this mold of the Elco piston area using 117 degree low melting point lead.
made this mold using 117ºF low melting point metal.jpg

-using 1/2 of the mold to get the profile shape of the dome this shows the a sample test piece and the 1/2 mold section.
HALF A MOLD OF ELCO CHAMBER, INSIDE OF TEST CROWN.jpg

-built this 3" diameter cutter with the blades shaped to fit the chamber curavture
TILTED BLADE SLOT AND SETSCREWS.jpg

-after machining the crown areas---slotted for the 2nd sparkplug---drilled and tapped for the dual sparkplugs---but haven't finished the chambers yet.

Wow Bill, thankyou for sharing this. I've never seen the combustion chamber side of an Eelco head but that is the shape I imagined.

It looks to me like the piston crown goes up in there. Am I wrong?

Also that second spark plug right there in the center. I'll bet there is very high potential here.

Thankyou thankyou for sharing this here. Please keep us in touch with the results when you bolt these to an engine.

[bill jones]

-this was a project I did maybe 8 years ago.

-I have no idea about the pistons---but I'd think they be a dome to fit up into in that chamber,

-seems like there 8 or more of the Kong as cast castings--that needed everything that needed to be machined done to'm---and then several other random heads mixed in that needed something or another done to them.

-I was not involved with them in any way after they left my shop----never heard any details.
------------------------------------
-the one picture with the unmachined chambers show there are like 5 different head bolt hole diameters.
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-I have no idea what the chamber sizes are----I did have that info but lost it somewhere in one of my computer's crashes.
-I usually try to get that sort of data into the photos---but I don't have any photos showing the CC's for some reason.

-I found some random CC numbers that range from 80cc of a center cylinder and 68.7---71---71.2---73.6---74.4--so I'd say low to mid 70's up to 80 cc's should be reasonable numbers.

[bill jones]

-here's some Ford flathead flow numbers

-the first two columns are out of Mike Davidsons flathead book---don't remember what the test pressure was.
-I just used Mike's flow for a comparison because that is the only flow numbers I have ever seen of flathead ford stuff.
----------------------------------------------------------
-the next two columns are Kenny Kloth's---one cylinder cut out of a block with a cylinder head hand carved out of plastic with the chamber very similar to what Kenny runs on his race engine.
-Kenny has a tracer mill---where he can copy the combustion chambers of his heads to another head one at a time--and he copied it to this one cylinder plastic head for the flowtesting.
------------------------------------------------------
-I tested this on my SF300 flowbench at 25" test pressure.

-I don't remember if it had any exhaust pipe but I don't think it did---and I don't remember what was on it for the radius inlet---probably a short tube with a flared entry.



----------Davidson-------Kenny
----------int---exh------int---exh
.100"----52----45-------52----47
.200"----93----82-------95----90
.300"---123----92-----122---100
.400"---139----na-----147---123
.450"-----------99------na-----na
.500"-------------------147----na

-this picture is Kenny's flowbench and his flowtesting setup for the flathead.

Kennys method of flowtesting a flathead.jpg

-one interesting thing about flowtesting the intake that I found was---I could leave the light spring off the intake valve---turn on the flowbench with the intake valve just sitting there closed---and the air flow opens the valve lifts the valve right up and close to .400" no matter what the test pressure is---and you can force the valve open to like .500" while it is flowing and it won't increase the flow---but it takes a fairly serious force to hold it open that extra .100" lift by hand.

[Nikolas Ojala]

The lion Speed Head has broken at least one Land Speed Record and more attempts are in the works.

• Lion Speed Head Secrets Of Speed Society, 4 March 2018.

It must be quite good then.