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Just want to jump in and congratulate you on a very informative post - one of the best that I have seen on the brickboard. The importance is the degree of analysis, regardless of whether there are a few "facts" that could be in dispute or opinions that some might not agree with.
And no, I have no problem with your posting specs from our street performance cam,or other cams, since this is a perfect context in which basics of the designs can be understood. But I should add a couple of things of a practical nature.
Our SP, or street performance cam, is not our only cam, though its the most popular in terms of meeting the most common requirements. This year, after dyno testing over the winter, we added another version of this cam for our 2.3 and 2.5 liter engines, the 5th different cam design for those engines. We usually stock about 20 cams, but these are divided currently among 8 different cam grinds right, with one more under development. We stock more of the most popular ones and only one or two spares for the less popular race and rally cams. And our grinds are not always the same from year to year, as we improve the grinds based on experience/testing in different engines - applications. And I much prefer to sell them based on application, and as part of a particular package, rather than selling them based on specifications.
Delays in being able to supply cams have largely been do to a shortage of cores,
which, as mentioned, have only one source. On one occasion I had to buy cores from Europe, that were originally made in the US, just so that we could have a few more cams ground for customers.
There needs to be more of a discussion of the rest of the valve train, especially the rocker arms. In terms of practical application, it does not make a lot of sense to dwell on minute difference in cam design and then throw on rocker arms that can vary the actual valve lift, at .200 cam lift for example, by .025 or more. (Someone with a lot of time can go back and compute the affect of that difference in actual rocker ratio on the duration at the valve at various cam lifts. )
In the real world, very few people ( not companies ) can afford the time or money to experiment with cam design by having a series of different cams ground for a particular application ( especially a popular one like 40 year old Volvos ), but anyone can experiment using changes in valve lash settings and rocker ratios to simulate cam differences - add a little more intake, decrease the exhaust, for example. This is where having original equipment rockers with different ratios can be turned into an advantage.
Just some thoughts before I really have to go back to work.
John
V-performance.com
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