To get back on topic, I have now completed a re design of the Norris RX cam to provide the same valve lift profile as with the original flat follower, but for use with a BSA type follower with a 1.25 inch radius pad.
This has been run through varying simulations up to 10500 rpm, as described in an earlier post, and only at this elevated engine speed was separation and bounce seen to be just on the point of occurring.
The simulation was re run, this time with only a pad radius change to 1.125 inch.
The results were to all intents and purposes identical, when comparing the output data no discernable differences were evident, unless going into four or five places of decimals to find a difference. Maximum and minimum velocity is unchanged, as is acelleration and jerk.
Going one step further, a design was produced to replicate the valve lift design when the 1.125 inch follower was used, and the two cam forms were used in an engine simulation to check for any difference in performance.
The performance predictions were again, to all intents and purposes identical, one trace laying on top of the other from 4000 to 10500 rpm.
The calculated difference at the peak power rpm of 9400 in the simulation was less than 0.25 bhp.
Anyone wanting to run at this extreme engine speed - be my guest! I'm not concerned whether the rest of the engine will hold together, my interest is only with the management of the valve train that would make such rpm possible.
This engine simulation was performed for a cylinder of 83 mm bore, and a 69 mm stroke. All other data input is not representative of any specific engine (as far as I know).
Re acotrel's mention of a 'cam spot' what exactly is meant by that, is it for real, or perhaps just another figment of scientific imagination?
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