safe a/f ratios
08-05-07, 07:39 PM
#1
Bang Bang!
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safe a/f ratios
i see anywhere from 11.1 to 14.8 on my a/g gauge is this safe?
it idles at 11.1 when i cruise its at like 13.6 and wen i get on it a lil bit it goes to 12.4.
how lean can it go before damaging the motor?
it idles at 11.1 when i cruise its at like 13.6 and wen i get on it a lil bit it goes to 12.4.
how lean can it go before damaging the motor?
08-05-07, 10:40 PM
#8
I would think that 10-15 psi would merit a rich mixture. especially once you start considering the ramifications of detonation.
On another note, in the PFC forum, there is a gentleman that runs 16:1 when cruising down the freeway, but under any load it goes to richer than 14:1.
On another note, in the PFC forum, there is a gentleman that runs 16:1 when cruising down the freeway, but under any load it goes to richer than 14:1.
08-05-07, 11:39 PM
#9
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um.....i have an autometer gauge.
i have an option between lean, stoich (wtf?), and rich. can anyone put a number to this? lol
i idle right on the edge between stoich and rich but under any acceleration it goes halfway into rich.
i have an option between lean, stoich (wtf?), and rich. can anyone put a number to this? lol
i idle right on the edge between stoich and rich but under any acceleration it goes halfway into rich.
08-06-07, 06:33 AM
#10
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Are you using a wide band O2 sensor and gauge or just the cheap gauge you splice into your stock O2 sensor? If you have the cheap one then you cannot tune by it accruately, you need a wide band for tuning.
08-06-07, 02:50 PM
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10.5 is supposed to be extremely rich for other turbo applications....11.5 -12 theoritical is very good and u are not afraid of high temps in the motor....but anything above that will cause high temps in the engine and we all know the results....
but this is theory when i was working on piston engines!
even the subaru impreza turbo BOXSTER engine was a bit strange...and dint like more than 11.5-11.7 , anythin more than that made the 3d cylinder get much damage (cuz the turbo was close to it....)
So what about wankels???
but this is theory when i was working on piston engines!
even the subaru impreza turbo BOXSTER engine was a bit strange...and dint like more than 11.5-11.7 , anythin more than that made the 3d cylinder get much damage (cuz the turbo was close to it....)
So what about wankels???
08-06-07, 06:41 PM
#19
Let walk through the steps... I`ve learn this the hard way by blowing a couple engines in my earlier years.
AFR'S
12.0-12.5 at idle is VERY ACCEPTABLE ON ROTARIES...PORT SIZE VARIES THOUGH.
14.7:1 at 25"hg and climbing to ->13:1
13:1 at 0psi WHILE TRANSITIONING INTO LOAD/BOOST/HIGH RPM
12.5:1 at 1 - 7 psi VERY ACCEPTABLE WITH CONSERVATIVE TIMING
12:1-11.5:1 at 7-20 psi VERY ACCEPTABLE WITH CONSERVATIVE TIMING
11.2-10.8 AT 22-30 PSI (10.8 FOR SAFETY)
10.5 IS VERY RICH. PROBABILITY FOR CARBONIZATION AND STICKING SIDE SEALS.
To each`s own...Good Luck.
AFR'S
12.0-12.5 at idle is VERY ACCEPTABLE ON ROTARIES...PORT SIZE VARIES THOUGH.
14.7:1 at 25"hg and climbing to ->13:1
13:1 at 0psi WHILE TRANSITIONING INTO LOAD/BOOST/HIGH RPM
12.5:1 at 1 - 7 psi VERY ACCEPTABLE WITH CONSERVATIVE TIMING
12:1-11.5:1 at 7-20 psi VERY ACCEPTABLE WITH CONSERVATIVE TIMING
11.2-10.8 AT 22-30 PSI (10.8 FOR SAFETY)
10.5 IS VERY RICH. PROBABILITY FOR CARBONIZATION AND STICKING SIDE SEALS.
To each`s own...Good Luck.
08-07-07, 08:16 AM
#23
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Try looking in the PFC forum, or searching under Chuck Westbrook, aka CEWRX7R1 for AFR's.
Many people run 16-16.5 for cruising with no problems, better mpg. At 12psi I would run at or just above 11.5:1, if you have 93 octane.
Many people run 16-16.5 for cruising with no problems, better mpg. At 12psi I would run at or just above 11.5:1, if you have 93 octane.
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