bigredexpress99

iTrader: (15)

Well with the 10 lbs of boost you are running in that 6.0 at approx 9.5-1 your effective compression ratio after 10lbs of boost is about 16:1. But when you factor in altitude for the ontario area (dont know where you are exactly, but the altitude seems to vary quite drastically across ontario, so we'll say 2000 feet as an average) is the FCR-[(alt./1000) * .2] which is 16-[.4]=15.6:1. Then you would have to figure the density altitude, which would vary from day to day, becuase of different atmospheric conditions, but you wont need to because the MAF "adjusts" for those changes.

So, with your 94 octane fuel, I would say your ok, you just need to do like you said and adjust for the overall decrease in quality due to winter additives and coldfer temps. And by the way, the enthanol is not hurting it at all. Thats what gets you that 94 octane which is probably somewhere in the range of a 91 to start with. You just need to adjust your tune by pulling a bit of spark where you have the knock. thats where I would start. Adjusting the calibration of the MAF should not be needed.

hog

I have also noticed some increased knock in my Fathers truck, I was wondering if the change to Winter gas formulas.

When I go racing I run 94 Sunoco in my truck, that stuff sure smells good when it burns. I think that all fuel in Ontario contains at least 10% ethanol. Ethanol has an octane rating of 100 while Methanol has a ratiing of 99. Both the numbers I quoted are using the (r+m)/2 method), same rating system as gasoline. Methonal has 50% the energy of gasoline and ethanol has 66% the energy content of gasoline.

They are opening another ethanol plant in Ontario to produce even more ethanol.

Hog

Jamesbond2509

iTrader: (1)

Well I changed the IFR tables slightly to dial in the Ltrims and most of the KR went away. I suspect the O2's are starting to get lazy also. The switching time from high to low is around .150