91 cai canned tune veruses 93 cai canned tune

[MIKEP300C]

so i a 300c 5.7 with a 180 tstat,with a k@n 63-1114 cai and flowmaster cat back.
i run only 93 octang from bp.
so my question is is the 93 cai canned tune not good for our cars i should run the 91 octang cai canned tune with 93 bp gas versus 93 octang cai tune
thanks in advance

[gdragich]

Think it depends on YOUR car. Some get better with 91 as the 93 causes their ECM to pull timing and it actually gives less power than 91 where the ECM doesn't pull timing. I have tried both and find better power and mileage with the 93. I was afraid to try it at first as we only have 92 octane. I made WOT fuel adjustments, pulled 1 degree timing at WOT and no ST KNK-and I monitor it with a Dashhawk at all times. Just datalog with the 93 and make sure your tank is ONLY 93 to be sure you have no ST KNK. WOT runs with AC on and off to simulate additional load.

[Quick]

WOT runs with AC on and off to simulate additional load.

The SRT8's (and I would assume the 5.7s) disengage the A/C compressor in WOT.

[MIKEP300C]

WOT runs with AC on and off to simulate additional load.

The SRT8's (and I would assume the 5.7s) disengage the A/C compressor in WOT.

yep ac disengaged when wot

[MIKEP300C]

Think it depends on YOUR car. Some get better with 91 as the 93 causes their ECM to pull timing and it actually gives less power than 91 where the ECM doesn't pull timing. I have tried both and find better power and mileage with the 93. I was afraid to try it at first as we only have 92 octane. I made WOT fuel adjustments, pulled 1 degree timing at WOT and no ST KNK-and I monitor it with a Dashhawk at all times. Just datalog with the 93 and make sure your tank is ONLY 93 to be sure you have no ST KNK. WOT runs with AC on and off to simulate additional load.

so when you say you made fuel ajustment and pulled 1 degree timing at wot explain, threw all wot fuel and timming power bands, did you retard it with 93 octang fuel or for 92 octang i still see knock with bp 93 oct and diablos 93 cai canned tune
thanks

ps i bought my catch can and its installed
Quick
no difference yet lol

[gdragich]

The changes in fuel and spark are only for WOT. I ran some WOT runs with AC off and AC on (simulates high load) and saw ST KNK. So I made the adjustments and no ST KNK. I can occasionaly see a small spike, like .5-3.0 in a low speed situation as MDS engages, low speed where it downshifts-kinda caught between gears, or some other off situation. I believe these are normal or "ghost" knock issues as the KNK just pops up and goes away in a second or two.

[Quick]

AC on or off has no effect on the load at WOT.
Having your cabin fans on full blast might add a tiny bit of load through the alternator?

[rfoker]

^^^ agreed. Let's say the fan has a fuse rating of 30amps. that means that your 160amp alternator is working 20% more to re-charge the system.
So if the alternator puts let's say an overall stress of 10% on the total engine output, total output reduced by the fan would be 2% at the highest reading. i think the drag alone from the alternator being hooked up, not even working per say is more of a drain than the actual 2% that is caused by the drag of your fan.

[Quick]

Haha, true. but it's ADDITIONAL drag .