Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Had flexfuel engines not been somewhat mediocre, would ethanol be more widely accepted?

Big Dave · 11-09-2018, 12:10 PM

FlexFuel is a "bridge technology" easing the path to a fuel that is not widely available.

It has a bigger problem in the US due to widely varying temperatures. I doubt E100 would ever fly in the US because of cold-weather starting difficulties. Low Reid vapor pressure and all that.

I've been looking at a FlexFuel setup flexing E85 and CNG. CNG requires "driveway fuel" to warm up the cooling system to keep the NG regulator from freezing.

An optimized CNG vehcle would run 13:5 compression with lots of spark advance.

E85 runs 95-102 octane, so it would be OK warm-up and purge fuel for a CNG car. 92 octane PUG is iffy, and requires a big spark retardation to serve.

11-09-2018, 12:10 PM	#27 (permalink)
Big Dave Master EcoModder Join Date: Jan 2008 Location: Steppes of Central Indiana Posts: 1,319 The Red Baron - '00 Ford F-350 XLT 90 day: 27.99 mpg (US) Impala Phase Zero - '96 Chevrolet Impala SS 90 day: 21.03 mpg (US) Thanks: 0 Thanked 186 Times in 127 Posts	FlexFuel is a "bridge technology" easing the path to a fuel that is not widely available. It has a bigger problem in the US due to widely varying temperatures. I doubt E100 would ever fly in the US because of cold-weather starting difficulties. Low Reid vapor pressure and all that. I've been looking at a FlexFuel setup flexing E85 and CNG. CNG requires "driveway fuel" to warm up the cooling system to keep the NG regulator from freezing. An optimized CNG vehcle would run 13:5 compression with lots of spark advance. E85 runs 95-102 octane, so it would be OK warm-up and purge fuel for a CNG car. 92 octane PUG is iffy, and requires a big spark retardation to serve. __________________ 2000 Ford F-350 SC 4x2 6 Speed Manual 4" Slam 3.08:1 gears and Gear Vendor Overdrive Rubber Conveyor Belt Air Dam