VEMS looks to be just the thing I was looking for to go beyond carburettors.
My project
- Guzzi V75/4 motorcycle
- 90 degrees V-twin, firing interval 270/450 degrees
- 750 cc, Normally aspirated. carburettors: 2x Dell'Orto 30 mm
- 65 Hp approx, 7000 rpm max.
- I already have a NB O2 sensor in one of the two exhausts (helped in jetting the carburettors. )
I will use the bike for street use only. Basically, I want to learn hands-on about EFI. I am not looking for a performance increase. Lower fuel consumption might be nice, though.
Trigger
- VR sensor on the camshaft that gives two pulses per camshaft rotation. So the pulses are 270 and 450 crankdegrees apart.
Other engine bits
Bought lots of second hand EFI bits from a Moto Guzzi Quota to make a start.. :)
- Two intake manifolds with Weber-Marelli IW 042 injectors (16.2 Ohm, 190 cc/min @ 3 bar)
- Throttle body with two 42 mm throttles and TPS
- Fuel pump (Weber PI021), filter, regulator (2.5 Bar)
- Various sensors and the original Marelli P7 ECU which I will not be using.
Plan
- Modify intake manifold to fit engine; fit throttle body, air filter, fit other EFI bits.
- Generate more timing info; either by multi-toothed wheel for the camshaft VRS or add VRS on the crankshaft. I see VEMS supports 2 VRS sensors. This is good.
- Buy VEMS! Nb. I would really like access to the firmware, as understanding what the firmware is doing is really a large part of the fun for me.
Eventually
- Have the VEMS do ignition as well as injection.
- One, maybe two WB02 sensors?
- Am thinking of alpha-n approach as that is what Weber-Marelli does on their system.
- I have a WM pressure sensor (PRT 03/03) rated at 100 kpa. In the original system, it is used as an ambient pressure sensor. Can it be used as a MAP sensor in this NA engine should I wish to do Speed/Density?