Buy MegaSquirt II fully assembled ($400).
Obtain an A14 or A15 EGI factory Datsun fuel injection manifold. Make sure it has:
- factory rising rate regulator and fuel rail
- fuel injectors included
- a throttle body. The Factory one is good for 92 hp
- the air regulator. It will run without this if you want to hold the throttle open while engine is warming up to 120F/45C
Everything else may be removed from the manifold.
- if you remove the EGR passage, fit a blocking plate
- an O2 sensor is not required,
- TPS is not needed
the only vacuum hoses needed are
- one to the fuel regulator
- one from the throttle body to the distributor
- manifold to MegaSquirt
With MegaSquirt you won't need the Datsun airflow meter. Instead, Megasquirt will calculate the air mass using a MAP sensor and and IAT sensor.
- MAP sensor is built into Megasquirt. Connect vacuum hose to manifold
- Obtain GM IAT sensor. Drill hole in your air cleaner-to-throttle body pipe, and hot-glue the IAT in place. Or use JB-weld. Threaded bungs are available if you want to get really fancy.
Use a 280ZX fuel pump, plumbed into the stock fuel line.. Connect the fuel reg output to.a line teed into the filler hose. If you keep the tank above 1/4 full no baffles or surge tank are needed.
Wire up the Megasquirt harness
- 12V
- earth/ground
- fuel pump relay
- injectors
- IAT
- Air Regulator
- EFI Water Temp
- Tach signal
Obtain a dropping resistor pack, and splice into injector wires
In the MS tuning software configure
Fast Idle Valve (FIdle): Solenoid Fast Idle Threshold: 120F
Nissan temp sensor -40F 30-33000 ohms 80F 2000-2500ohms 160F 360 ohms
CONSTANTS Required Fuel * displacement 1397cc (A14) or 1488cc (A15) * # of cyl 4 * injector flow rate 188 * desired AFR 13 Injector open time 1.0ms batt V correction .20 PWM current limit 1000% PWM time threshold 25.4 Fast Idle Threshold Barometric Correction: Off Control Algorithm: Speed Density [non-TPS] Injections per Engine Cycle: 1 squirt Injector Staging: simultaneous Injector Port Type: multi-port Engine Type: even fire
VE TABLE
Generate a new table based on your peak horsepower and torque figures ('Settings/VE Table/Tools/VE Specific/Generate VETable').
ENRICHMENTS EGO Step (%): 0 Warmup enrichment -40F 180% -20F 150% 0F 140% 20F 135% 40F 130% 60F 125% 80F 118% 100F 110% 130F 103% 160F 100%
Afterstart Enrichment: between 25-45%for 100 to 250 cycles,
Start your engine and let idle. Go to http://www.megamanual.com/v22manual/mtune.htm