With the installation complete (EFI, fuel system, sensors, previous ignition HEI), next is to fire up the motor.
The hand-held display was mounted to the dash inside the car, with the wire through a hole in the firewall and a grommet to seal the hole. The display is necessary to perform initial system setup and to monitor the sensors.
Completed the pre-start checklist for wiring connections, sensor wires away from exhaust heat, and checked for fuel leaks. Four gallons of fuel in the tank resulted in a fuel gauge read of 0% full. Adding fuel to nine gallons then showed only 25% full when it should read near 50% full.
Now ready to start the engine with the new EFI unit installed.
Turned the ignition key on and heard the in-tank fuel pump run up pressure, with no leaks in the new lines. The pump shut off after five seconds.
On the hand-held display inside the car, I selected Wizards. A fingertip is frustrating and inaccurate to make selections; I would recommend using the included stylus instead to make menu choices and fine adjustments. However the stylus does not attach to the display or fit in a slot anywhere, so how do you store the stylus so the little black plastic thing doesn't get lost?
For the Initial Wizard, I selected the Sniper TBI Type of 550-510/511/516 4-Inj 4150, then Cylinders 8, then Engine Displacement 355 for my overbored 350 cubic inch, then Target Idle Speed of 700 rpm (factory carb was 600 rpm), then Cam type of Stock/Mild, no Power Adder, then Ignition Type of Coil (-) to keep the previous HEI. The settings were uploaded to the ECU. Turned the ignition key off to reset the unit.
Turned the key to start up the first time. The engine cranked for less than 2.5 seconds then fired up, needed two seconds to reach a fast idle, and ran there for 6 seconds before dropping to a slow idle speed. Engine ran very smoothly with little speed fluctuations. The initial ignition timing was 14 BTDC on the HEI from before the swap, recommended is 15 BTDC.
I got out of the car to check under the hood and under the car for unusual sounds or fuel leaks. Nothing was dripping, and the engine seemed to be quieter at a cold idle than when carbureted with the choke on.
Ran the engine in a slow-moving car until it reached 180 degrees F in the coolant to see the Closed Loop and Learning indicators were active on the display.
When hot, the idle speed would climb not kick down. IAC POS read 0%. This made deceleration more involved since the idled engine would maintain speed and not slow the car. The printed and PDF instructions on page 44 of the instruction say to adjust the throttle blade angle, but I could not find mention of where this would be. This adjustment was shown only in a youtube video. Suggestion: I think the throttle blade angle adjustment screw should be shown in the diagram on page 7 of the instructions, not hidden in a video. The screw is in the typical carburetor position between the throttle cable attachment and the throttle shaft. After the blade angle was adjusted per instructions to show 2-10% on the IAC at hot idle, the idle speed kept to the setting. This makes sense, that the IAC would open or close to maintain this idle speed, and when closed to 0% it could not close any further to reduce speed.
The system would go into open loop when the throttle went closed near idle. Not sure if this is normal.
The Monitors - Sensors preset gauge package was the most useful. However the tachometer showing max 20,000 rpm was not helpful. Much later I read about Channel Scaling on page 60 that would set lower and upper ranges for each gauge. I reset the RPM to 6000 rpm max, then found that range usable while driving. This feature should be part of the initial setup at least for RPM.
With a good running engine in learning mode, the next post will cover the replacement of the MSD HEI with the Holley Hyperspark ignition coil, distributor, and control box.
