Quote:
Originally Posted by Chipper Chapman
Ferrea Competition valves (not the hollow ones as I was told they are illegal) and trend 3/8x.120 wall pushrods
|
Hollow stems are not illegal. According to Wesley Roberson,anyway, I've been running them ever since he told me they were legal about 8 years ago.
Your pushrods are a problem at the spring pressures you need. I suggest Trend 7/16" x 0.165" wall.
The intake is only going to hit between about 10-15 degrees BTDC and about 10-15 ATDC. After that, the piston is way out of the way.
I do not use clay to check. I check as run, complete the springs. Manley makes a tool to open the valve using the rocker arm. Check every 2 degrees between 25 degrees BTDC and 25 degrees ATDC. Your piston to valve clearance, as run, should be equal to or greater than your TOTAL piston to deck clearance. On the exhaust, you need 0.075", checked the same way.
I use the Comp 26115 spring, with the corresponding retainer and keeper.
My setup is good to over 8,000 RPM with the latest and fastest lobes Billy Godbold has designed for a big block at Comp. However, be aware that I'm using rectangle port cams, the lobes may be different. I have seen people run into trouble with the oval port stuff because it was designed for lower RPM. My stuff was all developed with the help of Billy and Tim Cole, who also did stuff for Wikle, Greene, and others. You need to talk to Billy, or at least talk to Dave McCarver and have him talk to Billy for you.