FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: fryedaddy on November 20, 2020, 05:09:05 PM
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i have a bbm headed 428 close to 11-1,.245 at 50 flat tappet,etc. question i may have asked before because i can be forgetful. i have my timing set at 33 as suggested buy the forum.i just filled up on 110 fuel.for max performance would i leave the timing alone or add or take away? or is there no relationship between octane and timing.
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Do you have a way to measure the results? ET or something else? Butt dyno?
My guess is that your are fine. I would still experiment in small increments, like +/- 2 degrees if you can measure the results in any way at all. I think most of the time for most situations the optimum total ignition timing is fairly constant for a cylinder head. Most people will say that for a given cylinder head the total ignition timing will not change much. I have seen anomalous results, though. I think low compression and high octane favors more ignition timing. Since you have 11:1 compression I doubt your optimum timing will be off much from the norm.
For example, I once had a low compression (9.3:1) FE with Edelbrock heads and race gas (I don't remember the octane) on the dyno. It liked a lot of total timing. Usually Edelbrocks like 37-38 degrees. We went to 41 and even 45 degrees and gained power before I said whoa.
BBM guys can take over now.
pl
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Ive done a few Dists for Blair Patrick and he has NEVER asked for more than 36 total on BBM Heads , as long as your certain your timing marks are Correct ( Ati's are of 7 degrees ) id try bumping to 36 , but doubt more will help BUT , a few extra and more octane than a combo needs can sometimes want MORE Total