Squish band w/combustion chamber in piston

[itgogitrev]

This is my first post here, I found this board yesterday and am impressed with the amount of factual knowledge here as opposed to myth of word of mouth. Anyways, here's my question.

How significant is the squish band for an engine that has a dished piston and flat surface for the combustion chamber on the head?

Most engines that I've had a chance to work on have had the combustion chamber in the head with pistons designed to have a decent squish band around the piston. This particular engine (VW's VR6) has a completely flat head with dished pistons. The piston itself is 90 degrees on all edges except for the inside top edge where it has a 7.5 degree cut across it to clear the head. The 'V' in the engine is 15 degrees but only uses one head, so most of the piston is never comes close to the head except for one area.

Basically, I'm curious as if there can be a piston made that has a 7.5 degree cut across the top so the air/fuel will be centered in the piston. I'm not sure if there is a way to do this AND keep the piston balanced. With the extra weight of the material on one side to compensate for the V, will this create problems? I can post pics if needed.

Thanks in advance.
Alex

 

[MikeHalloran]

Sounds a little like a 348 Chevy.

Given that pistons are normally made with offset pins anyway, I'm not convinced that you'd need to worry much about balance across the pin axis.




Mike Halloran
Pembroke Pines, FL, USA