Re: 393w build suggestion for valve springs
Hydraulic roller and OEM Ford Racing high rpm lifters. They have a ceramic check ball inside instead of the steel ball. I'm sure the spring has lost some pressure ( common) in the 25,000 miles the engine has seen. I initially ( mistakenly) used the GT40 springs that came on the heads out of the box. On the dyno the engine fell off at just under 6,000 rpm. They were between 92 and 100 from Ford. OK for a flat lifter hydraulic , nothing more. I had to put a chip in the Ford Racing ( MSD) box to limit the rpm to 7,000.
Experimental Ford parts collector.
Last edited by GT350HR; 02-08-2017 at 08:51 AM.