YIKES! Flathead Head Milled Backwards

If one were to machine 'billet' heads in tweo peices, would one still be allowed on this board? I think it's a killer idea. I fI had the $$ and resources, I'd do it just to prove it could be done. Thanks....this is very interesting.

 

I worked on a dual circuit cooling system for an offshore racer built at McLaren's about 15 years ago; on an OHV motor, about 80% of the heat is rejected to the combustion chamber and 20% goes into the block.

In a flathead - I'd expect additional heat goes into the block on account of the exhaust passages must travel thru it to get to the port.

Adding volume to the head isn't necessarily a good thing; heat transfer is a function of flow rate and film temperatures. If the flow rate drops far enough, the film temp goes to the to point where steam can be made - and steam is a lousy heat transfer mechanism.

I had this problem in my DOHC V8 motor; went to an electric water pump (constant flow) and licked the problem.

 

Steam is a killer - localized hot spots will always boil before the rest of the engine. That's probably one reason Ford restricted the flow at the front & another reason having restrictions in the outlet of the system is good, either washers or thermostats - by putting a restriction in the outlet, you create a positive pressure that can help keep the steam pockets from forming.


Backing up a bit, I've always wanted to do a two-piece head like Kong Jackson used to do. I think it's quite a reasonable undertaking for someone with their own mill & a lot of time doing it for the love of it instead of the money. Any takers?

I, for one, appreciate you taking the time to explore the heretofore unseen nether regions of a flathead! We need to find an old Edelbrock or Offy head to compare it too for grins! I expect we'll find something very similar...

 

Two part heads have been around a long time. The blub for these was "the top can be removed for inspection prior to fitting and removed again for cleaning"
Intresting to see the inside of those Ford heads though, I was amazed at how clean they were inside, had the recentley come of an engine?

 

No one (in this thread) has mentioned lengthened/hieghtened cooling fins on the heads. Good? Bad? Indifferent?

 

I'll tell what I think (but don't know if I'm right or not.) I think the fins on the aftermarket heads yield more surface area for heat dissipation. This may be better on a car that doesn't have a fan shroud and lots of louvers, (Like mine with no shroud, 1 fan and 174 louvers )

But I guess if they'd helped Ol' Henry might've put them on the stockers.

 

I'm hoping to have my first prototype 2 piece head done by summer...

 

Someday I hope to do some heads with exhaust valves and ports in them. Now that would be a cool runnin (half) flatty.

 

I can think of three sets of hand made solid billet heads in the drag racing world. All of them are on cars that burn nitromethane as fuel. There are probably more. The ones made by Rick Schnell are in two parts. At first he only had flat aluminum on the top side and they got too hot. He made a second bolt on piece with fins to fit on top of the flat piece and they cooled things down enough for him.

Ron Sterbenk milled up some heads with very high fins and there are a lot of them fairly close together.

Whitey McDonald has some of the most interesting. They are made from two flat billet pieces and a bunch of finned strips that he found at a local surplus materials yard. The first flat piece is has the chambers and is bolted to the block like any other head. The second flat billet is topped with the finned strips attached with small screws. The second piece attached to the first piece with allen head machine screws. Between rounds, the second piece with its fins still attached to the top is removed and dropped in a cooler full of water. When they have cooled down, they are reattached to the first heads until they get hot again. Then they are taken off and re-cooled. The process repeats itself until he is happy with the temperature of the first piece.

When I have a bit more time I'll look for pictures of all three.

 

Wow, I had no idea. That's killer.

 

An F-head V8, eh? I've seen some banger conversions for F-head & of course Jeep had one or two F-heads...that would be different. Perhaps it was done back in the day a time or two, but nothing that would be considered common that I can think of...

 

No details on this, but here's some modivation...

 

The F head thing has been done, I cant remember by who.
That looks like a little 60, at speedway?

 

Was it Alexander of Model-A fame? I'm reasonably confident I read that in a Don Montgomery book somewhere, but don't remember - not exactly what you'd call common though...

 

These 2-piece heads were posted on the MSN Ford site this morning made by Norman Frick. Apparently he made only 10-11 sets like these with a single spark plug. All others are 2 plug heads.

 

That F-Head for the V-8 60 was done by a fella named Tiny Smith in Texas. It was a "dry" head. I have seen a few. Wayno

 

I believe that the heads on Isky's roadster are F-heads, aren't they?

 

BTTT to join new thread!!

 

A well known (in antique car circles) antique engine remanufacturer friend of my fathers once told me that a properly cleaned and assembled flathead will run cool. He said that coolant sludge inhibits cooling significanlty and that these engines are at best over 50 years old. That's a long time to build up sludge and corrosion deposits. I don't have any first hand knowledge...yet but I have a '42-'48 100 horse engine that I want to put in a Model T.

 

As far as the restriction due to the coil mount at the front, that's a good thing, I'd say. The idea in designing piping systems is to make all flow paths the same pressure drop/flow rate (look up "reverse return" systems). Consider the coolant path for each cylinder as separate, even though they are common in the head. If the front didn't have that restriction, it would have the shortest return path and could flow too much water, starving the rest. With the restriction, the flow path is comparable to the middle cylinders. Whether this was intentional is debatable, tho.

Re: cooling fins on aluminum heads; they probably help absorb heat during quick spurts of power, to "store" some heat til it can be removed thru the cooling system, and may help prevent detonation during those bursts, but if you look at the heat transfer rates it is pitiful compared to a radiator, simply because there isn't really that much area. For one thing, heat has to transfer thru the (moving) water in the head to get to the fins. It can't hurt but it wouldn't make a huge difference IMHO.

 

I still cast these two piece heads. look up my website for all obsecure flatstuff!
www.brightworksmetalpolishing.com

 

Here's a suceeding thread I made after posting this one

Jim

http://www.jalopyjournal.com/forum/showthread.php?t=99053&highlight=yikes

 

Thanks for the original post and for bringing it back today - great stuff.
As for cooling passages, has anyone here ever tried Extrude Honing their water jackets?
I can't afford it, but always felt that Extrude Honing all the oil and water galleys would be a wise thing to do. Anyone???

 

Adding volume to the head isn't necessarily a good thing; heat transfer is a function of flow rate and film temperatures. If the flow rate drops far enough, the film temp goes to the to point where steam can be made - and steam is a lousy heat transfer mechanism.

And restricting the entry and/or exit does nothing at all for the speed at which the coolant flows past the exhaust valves.
What would help is length-wise dividers that make the water pass across the head more than once (but at higher speed) before exiting, typically across the bores first since they're cooler, then across the valves, then exit. It need not be an absolute seal (slight leakage is OK, it's low pressure), so it could be bolted in, made of out of copper bar stock (non corrosive?).
Fins inside the jacket help more than outside by exposing more iron to water.

 

Strictly speaking, an F head is overhead intake and sidevalve exhaust, like a Riley, Willys, Rover, Rolls, Harley JD, etc. (although that's just common usage, not a definition).

 

I have personlly seen a coffee can full of sand dug out of a Flathead block prior to rebuilding it

 

very cool

 

We ran bored and stroked flatheads in our '47- '48 Ford grain trucks in the late 50's-early '60's and had heating problems with them.

Extra thick radiators helped a bunch, but when you're driving through soft fields at 2-3 mph while a combine unloads the old flathead has to work!

Dad even bought an engine with 4 deuces on it to put in the "big" truck. He went with new Chevy trucks with 327's instead.

The biggest problem with heat is that the exhaust from two cylinders go through the block shareing the same port -- no way to get enough coolant through there so you've got to keep the coolant cool and clean and the belts and radiator clean.

If you do that they'll chuckle along all day.