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I will try it tonight. Since the 'dialback' feature of my new timing light was DOA I will aim to hit the 33deg M mark at 4000rpm and presume static will fall approx 12degrees.
 

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How are you accounting for knock? Are you pushing to audible knock and then pulling out timing? Knock begins prior to being audible, do you pull it back 3 degrees, 4 degrees... Yes, I know, every engine is different needs, and wants. Just ball parking.

Just trying to get a sense of the safety factor.
 

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Discussion Starter #523
I don't know if 33 degrees will give you all the available power with 9.7 to 1 Motronics. Has the head been skimmed?
I am running 10.8 to 1. 155 RWHP @ 6500 with 34 degrees adavance and 156 RWHP with 35 degrees. 4700 miles on the motor with lots of pulls to 7000 rpm. No problems at 34 degrees on 93 octane
 
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I'm going to swap over to the Shankle curve "E" this weekend. By the stats I have the only difference is the Shankle reaches 32deg advance 200 RPM sooner. I presume there are more differences such as the rate of change? I don't know how sensative my gut dyno is but I'm curious to see how it effects power and idle.
 

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Well i got ‘greedy’ And went straight for curve D. I timed it so that maximum advance coincides with the M mark which ought to mean I have about 33° maximum and 12° static. A very accommodating officer of the law issued me a written warning for what by rights probably should’ve been a ticket while checking this new curve so I will call it a day until tomorrow. but so far it feels quite good.
 

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I had some more seat time with the D curve this weekend and I like it a lot. If my questions have not made this obvious I am semi-literate in the terminology of tuning but extremely novice in the grand scheme of things. I have been thinking about some of the comments on this thread regarding pinging and I don’t know my ear is good enough to detect it and others have pointed out the damage can start before you can hear it. For that reason D seems a nice compromise: i have the steady idle that comes with advance starting at 1000, more static advance and the ‘security’ of keeping maximum advance just about where alfa had it. I don’t doubt I may be leaving some power on the table but you could certainly say the same thing about me not dialing in cam timing and other things about this motor that I am just really getting on the road for the first season.
 
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