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How to tune air fuel ratio.

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How to tune air fuel ratio.

Post #1 by djfalcon10 » Sat Jun 13, 2020 4:05 pm

Ok I need help on tuning my car. I have the Ford falcon wagon with the Paxton supercharger. Well I have a 650 blow thru carb. The jets on the primary are 74 and the rear is 78. When I am at idle it is 14.7 to 15.1. when I Cruse the car at 55 the a/f is 10.8 to 11.3. so if I go down two jets sizes, will my a/f go up to 11.5 to 12 .5. thanks for your help.

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Re: How to tune air fuel ratio.

Post #2 by xctasy » Sat Jun 13, 2020 7:35 pm

AFR = lambda x stoich, always


"" ... zbLrn-2jyw

161 Henry is the man to follow. Don't go too lean is my message, and don't forget that ignition timing influences vacuum, and vacuum influences air fuel ratio.

Focus on perfect low total advance first, then set afr.

just so you know

Your managing knock, advance and Air Fuel Ratios. Like a discordant band of thugs. ... Jx2RqwYBNE
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Re: How to tune air fuel ratio.

Post #3 by pmuller9 » Sun Jun 14, 2020 8:08 pm

When you are cruising you are only using the primaries so you would want to go down 2 on primary main jet size.

What is the WOT a/f ratio under full boost?

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