Thread: Greetings from the UK

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Don S. ...a quick, quick post.
spent the evening finally! getting my broadband connection - merciful release!!!
Haven't figured out how to get a photo of the engine - and car - up and posted
yet; as soon as I can, I promise I will. Spent a summer surfacing heads not too long back, and, boy, like knowing what goes into your sausages - you wouldn't want to know how much we took off some really expensive heads, got those things back on the road though; of course, those were sick puppies when we got them. Only ever came back if the guys really screwed up the re-assembly, the ones we did, fine. ...but this is much older tin, so, I am approaching with much greater circumspection. i'll try to find out just what combustion chamber configuration I've got in there before I even think of pulling the head, I believe there might have been a number of options... Been thinking from the start, that if i'm going to be milling, relieving , then I'll pick up another head to do the experimenting on. If it ain't bust - don't bust it!
my ignorance of flatheads is really showing here, can see i'd have to do most of the work in the block, rather than the head, am i right here?
I haven't even found an exploded diagram of a flathead yet, so if you or anybody knows of a site for same/could maybe post same, it would help a lot.
If I split the headers, then using a water-heated carb, like a Weber, could I think about plumbing it into the coolant system for carb heating?
i've been looking into home-building a flow-bench as this isn't the only head I want to be working on, have some 'bikes which will get onto the bench in not to distant future, too. I've found companies that'll sell a package, but they're not cheap. If you know of any sites that would be helpful to me, i'd appreciate the steer; it may take some setting up, but it doesn't look like rocket science, just practical engineering.
great story about the howie johnson guy - the original 'Otto man'!
thanks Don,
Len

FreewheelX1/Len, I don't have a machine shop and I am pathetic with a hand grinder but for what it is worth here are two pages from one of my alltime favorite hot rod books: "Speed and Power Handbook", 14th Edition, Newhouse Automotive Industries, copyright 1952. Most of the old folks on this forum know this so excuse me if I state the obvious. Most all the flathead engines have the main combustion chamber volume over the valves along with the spark plug hole and then a narrow squish area over the top of the piston. Thus if/when you shave the head you actually narrow the slot between the valves and the cylinder and end up reducing flow. The solution is to grind away the lip of the cylinder wall near the valves. However, the lost art is the hand grinding of the "relief" in the top of the block. On a long and heavy 8 cyl block you would need to find a very large bed on a milling machine. I suppose you could do a light cut on the top of the block to "deck" it to what ever you want relative to the pistons you have, but maybe something like a resurface cut of 0.005" would make sure you start out with a flat surface. Then you need to tilt the block only about 1 to 2 degrees moving the valve side down slightly. Then set up a milling routine to follow the outline of a head gasket to mill out the top of the block. Also you don't want the edge of the relieved block lip below the top ring of the pistons at TDC. Thus with a modern programmable milling machine the process could be made precise and equal on all cylinders, but that process sounds expensive to me. The alternative of tracing out the head gasket and using a hand grinder for the reliefs would require a lot of skill to make them all nearly equal and I don't see any way to cc the block the way you can with a head pocket. Anyway here are two pages on how to do it!

Note added in edit mode: It may not be necessary to slavishly follow the head gasket outline behind the valves since there is probably plenty of open space above the valves, so to make it simpler a rectangular shute the width of the narrow part of the head gasket should be sufficient to help flow back and forth over the edge of the cylinder on the valve side. You also want to avoid cutting away the edge of the valve seats so the shute could start right after the valve seat and extend toward the cylinder going from nothing at the valve seat to 1/8" depth at the cylinder lip. Good Luck!
Don Shillady
Retired Scientist/teen rodder

Don, deepest belated thanks for the above, am on hunt for a copy. Not enough hours/hands at moment, will respond more fully soon, again, thanks to you and everyone.
freewheelX1

freewheelX1, I came across this site while looking for information on flathead Ford V8s and it clearly shows the reliefs ground in the block.

http://www.34hotrod.com/HotRod/page7.htm

Don Shillady
Retired Scientist/teen rodder