Author: David Vizard

We have a two valve versus four valve debate currently running in our forum so I thought it would be an opportunistic time to release my patented PolyQuad head design for four valve per cylinder heads to GFN readers and the general public at large. Granted there are plenty of variations on 4 valves per cylinder and this begs the question as to what a PolyQuad head does better than a a current and typical four valve per cylinder head? Answer – everything, and compared to Honda’s VVT and other such variable valve timing systems costs almost nothing and can be produced in a typical head shop! To best appreciate how the PolyQuad concept came into being making a start at the two versus four valve debate would be as good a place as any. Two Versus Four. There have been some serious debates concerning combustion efficiency going on in the rums and from these it seems that it is well understood that there is more to producing torque and power than just filling cylinders with air and fuel. At low speed the engines ability to breath is hardly a problem as relatively, there is plenty of time to fill the cylinder as full as it is ever going to get. The key to making low speed torque is how much charge is trapped at valve closure and how...