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Paul, by the same token, the smaller of the cams I listed is 'only' a few degrees more than a stock Opel cam. However, it does add more power. I was just giving options....
I have not found any great amount of power from higher valve lift with Opels, not at least with an unmodified head. But the duration adds to both the power and torque curves, with the lobe separation and intake centerlines establishing 'when' the power band is strongest (relative to the duration) and 'how hard' it hits.
That is not a typo, the advertised duration numbers are as listed. This is why I do not hold advertised duration numbers in high regard...the @ .050" and the @ .200" duration numbers reveal the true character of the cam. The stock advertised duration of a solid lifter 1.9 cam is something like 310 degrees. But the @ .050" number is barely over 200 degrees. The roller cam in Samdog's sportwagon is listed as 284 degrees (much less than the stock Opel solid lifter cam). However the @ .050" number is 248 degrees!
Regarding the ignition timing, my usual recommendation of 35-36 degrees total timing holds true. Depending on the camshaft chosen, the baseline timing setting should be about 4-6 degrees. There's modest overlap involved so the cylinder pressures at idle should be strong.
Bob
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