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A9L2 Sealevel Spark Bias for GT40 3 Bar Heads

Posted: 2021 Sep 02, 20:11
by Chris93Cobra
Hi Mike,

Can you help me understand how to read your table and apply spark bias to the stock A9L2 table?

I have GT40 3-bar heads. So your table has 24 deg for boosted, 34 deg for n/a and 45 deg for cruise. How do I apply this against your stock table?

Thanks,
Chris

Re: A9L2 Sealevel Spark Bias for GT40 3 Bar Heads

Posted: 2021 Sep 02, 20:31
by decipha
post your tune

basically at na loads command 34 deg at wot in boost drop it to no more than 24

na load on a 302 with gt40s should be around .85 load and at 10 lbs around 1.3 load over 3k rpm. About .7 load below 3k and maybe .95 in boost down low.

Re: A9L2 Sealevel Spark Bias for GT40 3 Bar Heads

Posted: 2021 Sep 02, 20:56
by Chris93Cobra
Here it is.