Compression ratio and optimum ignition timing
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From: CA
Compression ratio and optimum ignition timing Stock, my car was 10.1:1 CR and maximum ignition timing advance was 28 degrees. If I put 6.0L heads on, have dished pistons, and now my CR is sitting around 9.4 or so, should I go up or down in ignition timing advance for max power?
This motor is still naturally aspirated, but it is possible that one day I will do forced induction. That's why the CR is lower. Just in case people are wondering.
<small>[ March 12, 2003, 08:32 PM: Message edited by: akw408 ]</small>
This motor is still naturally aspirated, but it is possible that one day I will do forced induction. That's why the CR is lower. Just in case people are wondering.
<small>[ March 12, 2003, 08:32 PM: Message edited by: akw408 ]</small>
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From: CA
Re: Compression ratio and optimum ignition timing </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Dipstick:
<strong> You should go up in timing. Keep in mind that if you go forced, you will more than likely have to go down again or up your octane requirements. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks, I'll try going up. But is there any reason why those who increase their CR also try to bump their ignition timing? I mean, there is this rule of thumb that more timing is always better, but I don't think it's always the case is it?
<strong> You should go up in timing. Keep in mind that if you go forced, you will more than likely have to go down again or up your octane requirements. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks, I'll try going up. But is there any reason why those who increase their CR also try to bump their ignition timing? I mean, there is this rule of thumb that more timing is always better, but I don't think it's always the case is it?
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From: Jersey boy
Re: Compression ratio and optimum ignition timing you can only go so far before you get detonation and a higher compression reduces the ammount of timing you can use. all a blower/turbo does is compress the intake charge so again more compression = less timing
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From: Jersey boy
Re: Compression ratio and optimum ignition timing and the reason that is (i think) is because you get more heat from the compression of the air so a bigger better aftercooler would cool the charge down and you can use more timing that on a non cooled charge
