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shovel · 03-10-2011, 06:14 PM

In this case, couldn't it be done dead-simple, like by mounting a TBI injector pod on an MPFI engine, run the MPFI system on ethanol but with a higher pressure fuel pressure regulator (so that more fuel per pulse escapes the injectors) and use manifold vacuum (or a combination of inputs) to modulate the delivery of straight gasoline through the TBI injectors?

I don't get all this talk about "ethanol resistant" fuel systems, if gasoline already has 10% ethanol and fuel handling parts don't fall apart in 30+ years why would a greater concentration of ethanol make them fall apart? Why would OEM's make fuel handling materials that can be damaged by ethanol when they KNOW a 10% ethanol fuel is going to be in contact with them 24 hours a day for more than a decade? At what point does the solvency of ethanol go from "absolutely no damage whatsoever" to "totally dissolves everything"? 15%? 30%? 43.33331%? And by what mechanism does ethanol go from absolutely zero harm at low concentrations to total harm at higher concentrations?

03-10-2011, 06:14 PM	#23 (permalink)
shovel Master EcoModder Join Date: Feb 2009 Location: Phoenix Posts: 593 Thanks: 106 Thanked 114 Times in 72 Posts	In this case, couldn't it be done dead-simple, like by mounting a TBI injector pod on an MPFI engine, run the MPFI system on ethanol but with a higher pressure fuel pressure regulator (so that more fuel per pulse escapes the injectors) and use manifold vacuum (or a combination of inputs) to modulate the delivery of straight gasoline through the TBI injectors? I don't get all this talk about "ethanol resistant" fuel systems, if gasoline already has 10% ethanol and fuel handling parts don't fall apart in 30+ years why would a greater concentration of ethanol make them fall apart? Why would OEM's make fuel handling materials that can be damaged by ethanol when they KNOW a 10% ethanol fuel is going to be in contact with them 24 hours a day for more than a decade? At what point does the solvency of ethanol go from "absolutely no damage whatsoever" to "totally dissolves everything"? 15%? 30%? 43.33331%? And by what mechanism does ethanol go from absolutely zero harm at low concentrations to total harm at higher concentrations? __________________ Work From Home mod has saved more fuel than everything else put together.