starcain wrote:Mutt wrote:So what is the lift and duration of the KHK stamped cam>
The numbered cams and the ones stamped KHK are exactly the same except for the KHK designation. Lift is about .375", duration I can't say. Patrick would probably be able to shed some light on that.
The French Owl and I compared cam data of some KHK cams a few years back and within experimental measuring error the data sets were essentially identical. The set I measured were the narrow gear variant labeled 1, 2, 3, 4. Don’t know which ones Patrick measured.
The plot below shows the 0 lash cam profile obtained. Although the 0.010” duration is not exactly 275 degrees, we must bear in mind that at these extremely low lifts, significant crankshaft rotation occurs with minimal change in lift so comparisons at such low lifts will certainly be subject to variability. The duration at 0.050” would be a better point for comparison where more significant changes in lift occur with crankshaft rotation. With 241 deg duration at 0.050" lift the cams are certainly not a large cam, especially in light of the engine size, but a nice solid cam that would be expected to provide good torque and a very smooth power curve, which they do.
To provide the reader a qualitative feel for the difference between a KHK lobe and a late model KR lobe (Leineweber grind of 1967 “J” lobe) a picture of the 2 lobes is included. After mounting and measuring the J lobes later this spring, will make an overlay plot to show the difference in valve motion of the 2 lobes and post here.
- KHK Plot.jpg (74.36 KiB) Viewed 38178 times
- KHK vs KR J profile low res.jpg (140.2 KiB) Viewed 38178 times