W124 build
W124 build
Through my experience with gas cars. The long runners are not as suited to high rpm. But these are not revving that high and port diameter is not bad. I do not think that is the hold up on these and the longer runners do support out of boost torque. So everything is a trade off. I really decided that the head and valves and cams were the limiting factor before anything else. And I was not going to go down that road.
As far as the cam is concerned it is more lift and a slightly longer duration on the one side of the profile. Like 10-12 degrees. So lobe separation changes a little bit but there is still no overlap and it is a small change. I would have to go back and look at the details. I put the n/a cam in and have driven it around but only at low boost and have not had it on the dyno yet. So I do not want to say that it did much or anything at this point but I have to believe it should show up at the higher rpm when the extra lift should be a benefit.