Vic,
The Vincent head is weak in the middle. I think the easiest modification to fix that was done by Max Lambky years ago when he had Godden cast up some heads with the two separate towers on the head attached. This fills in the area at the center of the head on the outside where a center sparkplug might go, but it appears to be a useful modification if it keeps the head shape stable while using fuel.
Despite this weakness, the stock heads seem to do quite well in all sorts of competitions. The machining for the Ian Hamilton pistons is fairly straight forward with two cuts on either side of the head that act as squish:
Thus, the weak area in the center of the head remains untouched. These heads have been used in this configuration for decades with very good reliability. The 90-degree shelf does not cause any detonation problems.
David
The Vincent head is weak in the middle. I think the easiest modification to fix that was done by Max Lambky years ago when he had Godden cast up some heads with the two separate towers on the head attached. This fills in the area at the center of the head on the outside where a center sparkplug might go, but it appears to be a useful modification if it keeps the head shape stable while using fuel.
Despite this weakness, the stock heads seem to do quite well in all sorts of competitions. The machining for the Ian Hamilton pistons is fairly straight forward with two cuts on either side of the head that act as squish:
Thus, the weak area in the center of the head remains untouched. These heads have been used in this configuration for decades with very good reliability. The 90-degree shelf does not cause any detonation problems.
David