A friend has timed all airhead cams he could get hold of, measuring valve lift in 2° crank angle steps with digital gauges with a resolution of 1/100 mm. He measured lift at the retainers.
He gave the data to me for my personal use, not to publish them in a forum, but today I'll make an exception.
I took the data for the 336 and determined the angles corresponding to 2mm valve lift and 2*1,39mm lift (2mm cam lift).
The angles are
| Ex-open | Ex-close | In-open | In-close |
|
| Measurement | 50 | 32 | 30 | 54 | (2mm valve lift) |
| Measurement | 40 | 24 | 20 | 42 | (2mm cam lift) |
| BMW Spec | 52 | 32 | 32 | 52 | (2mm ????? lift) |
Feel free to determine what the ?????? mean.