Posted by MoparNorm on Monday, February 25, 2002 at 1:53AM :
In Reply to: 318poly - hemi heads ? posted by RDavis on Monday, February 25, 2002 at 0:19AM :
The first modern Mopar V-8 was the Hemispherical design. Because of the limited sales of Chrysler vehicles and the high cost of Hemi production (two valve trains in each head) Chrysler experimented with a way to lower costs. This re-design resulted in the Poly. Same basic cylinder head combustion chamber, but the spark plug was relocated to the side of the chamber and out of the center of the head, to allow a single rocker shaft. The results is performance numbers close to the early Hemis. The wedge design is just that, the cylinder head resembles a wedge.
MoparNorm