Air/Fuel Thought for self tuning
08-10-2003, 08:22 PM
#1
Air/Fuel Thought for self tuning As is My understanding....our cars are set from the factory for an A/F of 14.6:1 (stoehic or perfect). This ratio is supposed to be the best Ratio for power and fuel economy and emissions......
But we dont care about Fuel economy or emissions if we are going for POWER.
Most of the Time Ideal for Power is 12.6:1 wich is approximately 15%-17% rich (really 16.66%).
so if your tables show positive #'s In theory you should see more power.... so doesn't it make sense to tune A/F to +15% rich and then advance timing until you start to see knock...then just back the timing off a little???
Somebody correct me if I am way off.... but this should make the whole tuning thing a lot easier....correct????
the reason for this is that I am thinking of buying a predator for tuning and doing it myself since shops all charge around $450 and If I change something I have to go get tuning again!!! and If I sell the car I can unbolt l cn un-bolt my "Bolt-ons" and re-flash back to stock.
Is my tuning Thought process correct????
Should I go buy Predator and do it myself??
But we dont care about Fuel economy or emissions if we are going for POWER.
Most of the Time Ideal for Power is 12.6:1 wich is approximately 15%-17% rich (really 16.66%).
so if your tables show positive #'s In theory you should see more power.... so doesn't it make sense to tune A/F to +15% rich and then advance timing until you start to see knock...then just back the timing off a little???
Somebody correct me if I am way off.... but this should make the whole tuning thing a lot easier....correct????
the reason for this is that I am thinking of buying a predator for tuning and doing it myself since shops all charge around $450 and If I change something I have to go get tuning again!!! and If I sell the car I can unbolt l cn un-bolt my "Bolt-ons" and re-flash back to stock.
Is my tuning Thought process correct????
Should I go buy Predator and do it myself??
08-10-2003, 11:31 PM
#2
Re: Air/Fuel Thought for self tuning If you are talking about LTFT's, they only represent what the PCM is doing to hold the AFR at stoich, not an actual rich or lean condition. A richer AFM when traveling at constant speed would just be wasting gas. As soon as you try to accelerate, the PCM richens the AFM anyway.
08-11-2003, 02:39 AM
#3
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Re: Air/Fuel Thought for self tuning LIke CAL said...but seeing your views also. You want a 13.1:1 for optimal performance, and cruise and such let the computer try to maintain that 14.7:1 stoich. Can the Predator do this? Yes, you will need some sort of way to tell what the AFR is, and preferably auto-tap or another scanner. With those you can send the info to your vendor, and they will write the program for you. Mine is right at 13:1, but when I spray, I add 2% fuel, giving me 12.4:1 or so, and I back off the timing 10% giving me a total of 27* spark. No KR, just fun.
