I have a slant head engine and I was wondering if it matters which way the spark plug is pointed (toward the front or back)? Will the direction effect performance in any way? Thanks.
Still I think that there is some consensus on the issue. The direction, I think, does have some bearing on engine performance. But I don't know what that might be.
But they seem to come from the factory with the spark plug pointing forward, so I just go with that.
It won't make any difference. The primary reason for the slanted plug was to provide a little more room for engine installation in some frames. Try it. Turn the cylinder head around and compare how your engine runs. You'll see no difference.