dwg86 wrote:Where did you get the .400 figure to mill off the rocker bosses?
The screw in studs have a wide base that tapers to 3/8" up the shaft. I mic'd it out to where the taper starts to the bottom of the base that mates to the surface. I then mic'd out the thickness of the guideplate. The total of all that came to just under .398" so I rounded up to .400" for ease of machining.
When using roller rocker arms, I wasn't comfortable with the amount of threads on the polylocks, because of the thickness of the pivot on the roller rockers. It only had about .375" of actual threads. The polylocks I got had .125" of a lip with no threads, so I machined them down to first of the threads, now I have .500" of biting threads. That is plenty.
By using this measurement, it keeps everything at pretty much the same angles. I had to have custom length pushrods because of the larger valves, with different lengths, I had installed. I had to sink them to adjust not only for the LS1 length, but also the chamber work that was done to get to 65cc's. If you install an adjustable valvetrain with a standard head, (using those same measurements) you should be able to use the stock length pushrods.
I am speaking in general terms. If you do this conversion, you should always take the measurements of your parts, then make the cut based on your measurements. This will at least give you a guide.