A/F ratios

Old 02-22-2008, 06:03 PM
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suicidebomb
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Default A/F ratios

How lean can one go and still not get into detanation in a N/A engine on methanol? For instance in my sbc 406 about 4.75/1 is as lean as i have tried. I still get quite a bit of oil dilution, so i assume I am still pretty rich, but I am afraid to go much leaner for fear of burning a hole in a piston. does anyone know if I can go, say 5/1 or maybe a little more 5.25/1 and still be safe, and maybe solve some of the dilution or at least cut back on it some.
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Old 02-22-2008, 06:15 PM
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johnracer
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I don't really know about a/f ratios, but, if it were mine. I'd tune it to run the best and quit worrying about it...
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Old 02-22-2008, 07:43 PM
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suicidebomb
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4.75/1 was its best E.T. and speed to date, and I would like to try it leaner, but I am worried about burning my engine down. However, I still appreciate your input, thanks.
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Old 02-22-2008, 11:50 PM
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zipper06
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Originally Posted by suicidebomb
4.75/1 was its best E.T. and speed to date, and I would like to try it leaner, but I am worried about burning my engine down. However, I still appreciate your input, thanks.
Where did you get these #'s from?, you need to run an EGT and keep the #'s around 1100 degrees on topend. if you go leaner than that you will burn something down.

JMO

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Old 02-23-2008, 04:15 AM
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Don't be afraid to lean it out. You'd have to go really, REALLY lean to hurt it unless you're running nitrous or some sort of forced induction with a lot of boost....
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Old 02-23-2008, 04:21 AM
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Another thought, if you're injected, the oil delution could be the barrel valve adjustment, or running the engine too cold w/carb or injection...
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Old 02-23-2008, 05:24 AM
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Like ZIP said you need an EGT.
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Old 02-23-2008, 05:35 AM
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Where can I get an EGT?
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Old 02-23-2008, 05:37 AM
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http://www.ronsfuel.com/accessories.cfm
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Old 02-23-2008, 09:41 AM
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Also here for duel setup $300.00

Zip.

http://www.exhaustgas.com/ProductDet...ID=sub2&RepID=
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