"Offsetting" the head

[Anonymous]

In a previous post, you said"Slightly off the subject, would offsetting the head toward the intake side on the block thereby getting the valves more over the cylinder and eliminating at least part of the ledge caused by the chamber overhanging the block deck help power output any?"
Curious if you meant this literally? Looking at edwins site, the cross-section view, doesn't look like you'd be moving it much, maybe 1/4"-3/8"? Couldn't you get the same effect by grinding on the head?Looking at the stock head, the valve clearance recess area is shaped like an oval.It seems like it could be ground to more of a round shape, or more acurately a heart shape, with the bottom of the heart, (side where the sparkplug is)round, and the "v" part of the heart coming down between the 2 valves. If I could figure out how to post pictures of what I'm talking about, I would.(but I can't). Jim

 

[Asa]

do you have the pics in a digital format? on your computer somewhere?
if so, we can walk you through posting the pics

PM me if you'd like some help

 

[Anonymous]

See e-bay item #290206358849, or 160145764515; existing or stock head. Now look at the 4th pic down, at http://www.mpgresearch.com/viewtopic.php?t=1905. This is something like what I'm talking about. Most of the ledge on the plug side is because the recess is shaped sort of like an oval racetrack i.e. the long sides are parrallel. You could use the head gasket as a pattern, to make that side more round, like the cylinder. Anyway, thats what I was thinking....Jim

 

[Anonymous]

Now I see why it wouldn't work; The relief area doesn't need to be ground, it needs to be filled in! Duh! Other than moving the head over, as suggested earlier, I wonder if ya could mill about 1/2" off the deck of the head, then take a piece of 1/2" steel plate, and put the valve relief in it, in order to incorporate "modern" squish or 'soft head" techniques in these old 6 bangers.Or, cast a new head from scratch. Too bad....Jim

 

[flatford6]

Actually, I was the one that suggested offsetting the head toward the intake side to reduce or eliminate the ledge caused by the combustion chamber hanging over the block deck. The ledge is in the highest intake flow area near the spark plug. These engines share that dreadfull feature with the 292 series v8 engine. The cure was to grind a taper section from just above the top ring travel to the combustion chamber so that the air-fuel mixture leaving the valve on the spark plug side of the chamber didn't hit a right angle ledge formed by the combustion chamber. The problem with this cure was an increase in the size of the combustion chamber and it fouled up the shape too. Moving the head solves both of these problems if it could be done. I checked the web site you recommended but there were only 3 pictures, no 4th picture and it concerned swirl in the incoming fuel air mixture.

 

[Anonymous]

After thinking it thru, I'm reconsidering yourn idea to offset the head. What would be the considerations? New headbolt holes in the head and block? And getting the valve lifters to line up?And water jacket holes and any oil passages? What else? JIM