Wondering people's impressions of the Lund flex fuel tune. I got 47lb/hr injectors and am eager to get that tune. How's it run with straight/mix of e85, straight e85 and with 93? Could the tune not be as good as a straight up 93 or e85 tune?
Lund Flex Fuel Tune- Anyone Running It?
- Thread starter evanjp
- Start date
I am not running Lunds but do have flex fuel enabled, the principal is the same, the ECM infers the ethanol percentage based on fuel adjustments needed to achieve stoich(lambda=1).
You can mix e85 in the tank freely and with out care of how much is in there. you could do a full tank, half a tank, a gallon, 2 gallons, 4 gallons, no gallons. The ECM does not care, it will simply repoll after fuel level increases by whatever percentage he sets in the tune.
It should drive 100% the same as it did before the tune. No bucking, no stalling, nothing like that. Now something that will be affected is your cold starts, e85 is harder to start in the winter, so you should prob mix in a few gallons of 93 during cold months. I haven't tested it yet since I'm in Texas, but there are cold start spark and fuel tables for flex fuel, so this may not be so much of an issue.
You can mix e85 in the tank freely and with out care of how much is in there. you could do a full tank, half a tank, a gallon, 2 gallons, 4 gallons, no gallons. The ECM does not care, it will simply repoll after fuel level increases by whatever percentage he sets in the tune.
It should drive 100% the same as it did before the tune. No bucking, no stalling, nothing like that. Now something that will be affected is your cold starts, e85 is harder to start in the winter, so you should prob mix in a few gallons of 93 during cold months. I haven't tested it yet since I'm in Texas, but there are cold start spark and fuel tables for flex fuel, so this may not be so much of an issue.
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This is not completely accurate. You need to drive gingerly for about 20 minutes while the ECM relearns the fuel trims. Not doing so can cause the car to exhibit E85 spark advance on a potential pump gas mixture, which is not good.
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To gain it's max potential, tank needs to be right at empty. Then fill with E85 and let it idle for 10-15 mins or gently drive it.
But, you can add 93 to the E85, say if you are driving with a tank of E85 and need to fill up since the next gas station is a while away or they don't have E85, then you can mix. But if you have half tank of 93 or 91, and mix with E85 and then later with half a tank you fill with 93/91, just no point.
Or like my situation, the gas station that is the only one with E85 stops selling it and the next station with E85 is 75 miles away.
But full tank of E85, you will def tell a power difference and watch you gas gauge go down quicker....but worth it.
But, you can add 93 to the E85, say if you are driving with a tank of E85 and need to fill up since the next gas station is a while away or they don't have E85, then you can mix. But if you have half tank of 93 or 91, and mix with E85 and then later with half a tank you fill with 93/91, just no point.
Or like my situation, the gas station that is the only one with E85 stops selling it and the next station with E85 is 75 miles away.
But full tank of E85, you will def tell a power difference and watch you gas gauge go down quicker....but worth it.
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