[darkpuppet]

ZTWsquared,May 26 2009, 09:29 PM Wrote:I tried Sunoco 94 with my XCal 94 tune once and it drove like crap relatively speaking.

I originally blamed the tune ... perhaps it was the addition of the ethanol the car didn't like.

I haven't tried the 94 in the Fusion yet and now don't plan to ... I'll be replacing the 94 tune with a 91 tune for CAI ... yes Daniel I bit the bullet today and ordered the Steeda CAI with removable insert - Steeda says it's worth 8 hp and 10tq with the insert, and even more with the insert removed and a tune. We shall see.
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Unfortunately, there's a lot of variables in effect that could have affected your performance.

The thing with ethanol is that it burns slower, and at a stoichiometric ratio of 9:1 whereas gasoline burns at 14.7:1, which means alcohol burns richer, but effectively leans your running mixture since you're running a/f ratios meant for gas.

And if you're running lean(er), combustion temps can increase, affecting your knock sensor, etc., etc., etc.

So consider your car needs to 'learn' or be tuned correctly and then consider that the fuel could have been stored in the sunoco tanks for ages and bonded with moisture, separated, etc... , there's plenty of reasons why your car could have been running less efficiently that day.

[edit]a good read on the disadvantages of alcohol as fuel can be found here

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