MikeH
Diamond Level Sponsor
Mike, Even with 5 degrees advance at 9.3 to 1 the Dynamic compression is only 6.8. At 10 to 1 it is perfect at 7.3.
Your meaning here is that at 10:1 I would run the cam straight up, correct?
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Enjoy.
Mike, Even with 5 degrees advance at 9.3 to 1 the Dynamic compression is only 6.8. At 10 to 1 it is perfect at 7.3.
Mike, That was before I knew crank degrees, not cam degrees. 5.3 or 1 tooth on the cam is too much. it would be 10.6 at the crank. The more I think about it would be better to just grind 4 degrees advanced into the cam specs.
You sure 1 tooth is gonna be 8 degrees?
Remember that cam degrees double the crank degrees (which is what the engine simulator uses).
You want 4 degrees at the cam to make 8 at the crank. You may be able to get there with an offset key. Otherwise you may need to make a timing adjustable cam drive or a custom cam gear.
It all still goes back to why wasn't this an issue with past conversions.
Think I finally found something to clear it up.
Remember: The camshaft angle is half of the crankshaft angle, therefore the camshaft will correspondingly advance or retard 1°, 2°, 3°, or 4°.
So moving the cam gear one tooth (5.3 degrees) changes the timing 10.6 degrees at the crank.
Found in the article below.
http://www.compcams.com/(S(yyboabakneda22nutbxo1jvq))/Instructions/Files/COMP4-153.pdf