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Gold TX Sleeper backyard mechanic
Joined: 05 Feb 2002 Posts: 509
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Posted: Sun Mar 10, 2002 6:38 am Post subject: Compression V's Octane rating |
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Whats a reasonably safe compression ratio to run on pump fuel ? How high can you go reliably with Super ? I've read about standard engines with 10:1 on Optimax or a similar premium. I only run the premium unleaded with a bottle of Pro Strength Octane Booster on weekends when street racing but run super during the week, so how high could i jack up the ratio while only feeding it Super & Optimax on the weekends without hitting reliability/detonation issues?
Cheers,
Jasyn... |
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MatMan tinkerer
Joined: 04 Oct 2001 Posts: 280
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Posted: Sun Mar 10, 2002 4:49 pm Post subject: Re: Compression V's Octane rating |
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Depends on your timing as well, just FYI |
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Mooch backyard mechanic
Joined: 17 Oct 2001 Posts: 573
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Posted: Sun Mar 10, 2002 8:08 pm Post subject: Re: Compression V's Octane rating |
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and ur camshaft overlap. I'd go 9.5:1 to be safe, and run pulp. Drop a catalytic converter in ur exhaust and change the fuel filler neck.
Mooch |
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Gold TX Sleeper backyard mechanic
Joined: 05 Feb 2002 Posts: 509
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Posted: Sun Mar 10, 2002 8:41 pm Post subject: Re: Compression V's Octane rating |
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I've been told that a higher rating gives me the scope to advance the timing by a few degrees ? Is there a guideline to follow with a certain octane rating and ignition timing. I still haven't been taught what total timing and all that sort of jargon means, all i know is the basics of undoing the nut on my dizzy and advancing and retarding with a timing light. Could you shed a little light on this subject for me?
Cheers,
Jasyn...
P.S Once upon a time i asked if anyone knew roughly what the compression ratio would be with an 1800 head on a G200 block (all standard including gasket). Do you have any ideas on what it may be ? |
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Slug tinkerer
Joined: 06 Oct 2001 Posts: 196
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Posted: Mon Mar 11, 2002 7:21 pm Post subject: Re: Compression V's Octane rating |
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Optimax will tolerate an 11:1 comp maybe a little higher with a good ECU and super will should be good for about 10.7:1 once again a little higher with a good ECU... Michael |
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Gold TX Sleeper backyard mechanic
Joined: 05 Feb 2002 Posts: 509
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Posted: Mon Mar 11, 2002 11:44 pm Post subject: Re: Compression V's Octane rating |
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Cheers... I'll try to get it into the 9:1 to 9.5:1 range. It should be sufficient and reliable enough to keep using the same diet of fuel i'm feeding it without any dramas and a bit of a hike in power.
Jasyn... |
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