Buy MegaSquirt II (or MicroSquirt 2) fully assembled about $400 USD or $500 AUD off eBay.
Contents |
Manifold and Injectors
Obtain an A14 or A15 EGI factory Datsun fuel injection manifold.
Make sure it includes:
- the factory rising rate regulator and fuel rail
- the fuel injectors included
- the factory 2-pin water temp sensor
- the throttle body. The Factory one is good for 92 hp
- the air regulator. It will run without this if you want to hold your foot on the throttle 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
Sensors
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 from a Chevrolet or Holden. 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.
* MegaManual * GM IAT Sensor 12146312 $10 RockAuto.com * GM sensor connector 12162193 $5 RockAuto.com
Fuel System
Use a 280ZX fuel pump (or Walbro inline pump), connected to the stock fuel line coming from the tank.
* 280ZX Fuel Pump $45 RockAuto.com
Run a regular fuel line back to the the filler hose and Tee it in. If you keep the tank above 1/4 full no baffles or surge tank are needed.
From the fuel pump output to the fuel rail, use EFI-rated fuel hose and EFI hose clamps. Use a 280ZX-style fuel filter.
Nissan EFI fuel pump with damper can be mounted in rear of car or in engine compartment
280ZX EFI fuel filter $3 RockAuto.com
Wiring
Wire up the MegaSquirt harness
- 12V
- earth/ground
- fuel pump relay
- injectors
- IAT signal & ground/earth
- Air Regulator
- EFI Water Temp
- Tach signal (coil negative terminal)
For full details, see http://www.megamanual.com/mtabcon.htm#wire
Obtain a dropping resistor pack, and connect to injectors
See main article: Dropping_Resistor
ECU Configuration
Download at http://www.diyautotune.com/softwarelinks.htm
- Mac
- Windows
- Linux
You have a choice:
- TunerStudio free version (most popular software for MegaSquirt)
- Free version supports all MegaSquirt features
- SuperTunix open source
In the 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,
Software Tuning
Start your engine and let idle. Go to http://www.megamanual.com/v22manual/mtune.htm
And start tuning.
A big help in turning is to fit an Air Fuel Ratio Gauge. MegaSquirt 2 can directly read the wideband output of the wideband controller, but more importantly you can see the A/F Ratio on the gauge.
See Main Article: Oxygen_Sensor#Air_Fuel_Ratio_Gauge
The paid version of TunerStudio has a software auto-tuner which is supposed to be great, but it still requires some work (it's not totally automatic).