Friday, February 21, 2014

Reading Camshafts

The 428 Ford that has been a long term project in our shop is in it's final stages of the build. We have to depend on other vendors for certain item's and camshafts are one of them. Most of the cams used here are a custom grind to our specs. The habit we have gotton into is checking the work of our vendors to avoid any problems later. When the cam arrived it was slid into the mocked up engine and one of our cam reading tools( this tool is custom made in our shop) was installed in the lifter valley. The next step is to check lobe lift. The process is simple. We start by zeroing the dial indicator on the base circle of the cam. The cam is rotated around and is read at max lift. The cam card provided by the grinder tells us what the lobe lift should be. After this is verfied as correct we can then put the degree wheel on the crank and reverse engineeer the cam. All event openings and angles are checked to prove they are mathamaticlly correct. It is rare that the grinder screws up a job but you just can't take any chances at this point. We also measured our pushrod length so we can send the dimensions to our pushrod vendor. We used a tool that was also built right in our shop. It is really just an adjustable rod that can move up and down to find the best rocker arm geometry. Take a look at the rockers and shaft assembly. These were made for us by Harland And Sharp. A company that has been in business forever and builds some of the best rocker arms for racing engines. These are a real work of art. Final assembly is next.