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 540 crankdegrees apart.
- can you elaborate on this ? 270 + 540 = 810 (NOT 720)
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?