greetings all. i have installed a Labonte h2o/alc injection setup in my BB 95 e350. i also installed an adj fuel pressure regulator. part of the water/alc injection theory for a N/A motor is to lean out the fuel mixture as you are replacing some of the fuel with the h2o/alc mix that has higher octane and a cooling effect on the intake charge. factory setting calls for 40psi fuel rail. anyone have any thoughts on leaning out the mixture? as in at what press setting you will actually start affecting the mixture?
any thoughts are appreciated. i have done h2o inj before, in fact i started doing it in the 70's, but never on a fuel injection engine...
I suppose, install a fuel pressure gauge and a a/f gauge and see where goes? A good wide band a/f would be best, but I suppose a cheaper one run by a $15 o2 sensor will give you readings to watch/compare.
I know from past experience of my friend racing his 87 Mustang with speed density computer that fine adjustments(lb or so) on the fuel pressure made changes in his times.
Adjusting the fuel pressure will not produce sustained changes in A/F ratio, the computer will counteract the pressure change within a few minutes driving time.
The whole EFI system is based around the stoic 14.7:1 air/fuel ratio, the narrow band O2 sensors in these vehicles don't actually measure the ratio they just indicate if the mixture is lean or rich of the 14.7:1 baseline, and the computer is also programmed with this A/F ratio as the baseline. As a result producing a mixture leaner than this is not at all simple, a wideband sensor that can be programmed to provide the narrowband switching at the desired A/F ratio will be needed.
__________________
Paul O
1990 F150 4x4 XLT X-Cab 5.0, 3.55, Comp 35-349-8, Flowtech LT's to 3" single, FRPP Mass Air Conversion
Under construction: '85 351HO, Dart Iron Eagles, 1.6 RR, Typhoon intake, Crane 444232, 24lb Injectors, TweecerRT, Innovate LC-1 wideband O2
1990 Ranger 2wd, 2.3 Briggs & Stratten, 5-speed, 3.08 gears, and now power steering!!
thanx guys. paul-o, that was about what i expected. i expect most of my gains to come from additional timing advance - i am already running +5deg over base timing of +10, but have not done a lot of checking to see if the pooter is pulling it back and negating much of the "improvement".
neil
will report when the critter is back on the road.
When I had my new '96 F350 Dually 460/auto I bumped the timing(after pulled the pin out) and it ran WAYYY better when I bumped it up to around 13 degrees(seems stock was like 8). It wouldn't get outta it's own way when stock, it would actually squeal all FOUR tires out back after. I also removed the restrictions inside the air box tubes. Never saw any great MPG gains, only drivability improvements. Back then gas was CHEAP, so 10 mpg was fine.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.
