My Megasquirt 3X conversion
11-01-2011, 09:40 PM
#48
Thread Starter
Ducman - never even thought that way. I figured I would need to keep the stock Euro S throttle body because of the cable linkages for the trans, gas pedal, and cruise control. Just wanted to make things as simple and clean as possible with mostly stock parts for this car. Being Euro S, I'm sure I'll have enough airflow with this intake/throttle body for my driving style.
Thanks Sam.
Thanks Sam.
12-04-2011, 09:07 PM
#49
Thread Starter
Finally got to the point on the engine conversion where I can now focus on the wiring harnesses. Both the new one for the engine, and reworking the engine bay harness to eliminate unneeded wires and add in new circuits. Some small details are shown in the pics - things I thought others might like to know for their conversion.
The TPS blade I made drives the Ford TPS which has an internal spring to keep it tight to the blade. Since the TPS had more than 90deg of movment, I got the blade clocked in the butterfly shaft so the TPS is not quite at zero, marked the location, then ground a small flat on the blade stub, and a groove inside the hole in the butterfly shaft using a Dremel bit. This will create a formed-in-place key when the JB Weld epoxy cures. During MS3 setup, you have to calibrate your TPS for 0-100% open, so I figured it would be good to not be at the slack end of the TPS motion. I haven't tested the TPS voltage yet, but mechanically it works great. When the throttle body is installed, the TPS is a close fit to the new IAC hose and oil separator vent hose, but luckily I planned for this, and it fits nice! On a roll now, got the extruded fuel rails marked, drilled and tapped, and trial fitted on the engine. All my brackets I have made still need to be plated, so will have to disassemble at some point, but good to have all together right now for the wiring to be started. The yellow injectors in the pics are 19# just there for test fitting, I'll be using the 24# injectors when final install happens.
Also set the crank and cam trigger wheel timing tonight - it has been a long time coming and glad I did it now or I could have forgot easily. Following the MS manual, I set the crank trigger at 40deg BTDC. The cam trigger should only be ~60deg BTDC, but because of where I mounted the cam sensor and the holes in the cam gear, it ended up at 105deg. I think this will be ok be setting the degree # in the software.
A couple overall pics show the Aeroquip AQP hoses and the FP regulator at the front. Once the fuel pressure is set, I'll remove the guage and install a plug. Now I can focus on the wiring on the engine, but will jump sideways back to the car. I finished the afternoon by working on stripping out the interior.
The TPS blade I made drives the Ford TPS which has an internal spring to keep it tight to the blade. Since the TPS had more than 90deg of movment, I got the blade clocked in the butterfly shaft so the TPS is not quite at zero, marked the location, then ground a small flat on the blade stub, and a groove inside the hole in the butterfly shaft using a Dremel bit. This will create a formed-in-place key when the JB Weld epoxy cures. During MS3 setup, you have to calibrate your TPS for 0-100% open, so I figured it would be good to not be at the slack end of the TPS motion. I haven't tested the TPS voltage yet, but mechanically it works great. When the throttle body is installed, the TPS is a close fit to the new IAC hose and oil separator vent hose, but luckily I planned for this, and it fits nice! On a roll now, got the extruded fuel rails marked, drilled and tapped, and trial fitted on the engine. All my brackets I have made still need to be plated, so will have to disassemble at some point, but good to have all together right now for the wiring to be started. The yellow injectors in the pics are 19# just there for test fitting, I'll be using the 24# injectors when final install happens.
Also set the crank and cam trigger wheel timing tonight - it has been a long time coming and glad I did it now or I could have forgot easily. Following the MS manual, I set the crank trigger at 40deg BTDC. The cam trigger should only be ~60deg BTDC, but because of where I mounted the cam sensor and the holes in the cam gear, it ended up at 105deg. I think this will be ok be setting the degree # in the software.
A couple overall pics show the Aeroquip AQP hoses and the FP regulator at the front. Once the fuel pressure is set, I'll remove the guage and install a plug. Now I can focus on the wiring on the engine, but will jump sideways back to the car. I finished the afternoon by working on stripping out the interior.
12-04-2011, 09:23 PM
#50
forgot to ask..... why are u using the CIS flow thing, and not a U bent from the throttle body? still following this with GREAT interest. i will get with you on coil brackets soon.
12-04-2011, 09:33 PM
#52
Thread Starter
Duc, If you mean the lower air plenum the throttle body sits on, Just because? I want to keep the stock airbox and intake look, and it seemed like the easiest path to take instead of hunting down different parts and combining them.
12-04-2011, 09:34 PM
#54
12-18-2011, 10:17 PM
#56
Thread Starter
Wiring for the conversion to MS3x has begun! Started with the '80 ROW Current Flow diagrams, and figured out (correctly I hope) where to change a few things in the current engine bay harness. The original coil wires, the TSZ spark box and connectors, and the 4 and 6 ohm resistors are removed. It looks like the T14-10 wire from the starter going to the now missing resistors continues to the control side of the fuel pump relay, so I pulled it back and ran it toward the CE panel. It wasn't quite long enough, so spliced it into the Q1 wire which is no longer needed (WUR and Air Valve) to get the length, then inserted my impact safety switch in this line and connected to O6 (wire #15). I plan to install it next to the MS3 box in the right side of the passenger footwell, where the emergency medical kit used to be. This is a Ford switch, and I confirmed it is NC operation, so should cause the FP relay to open in the event of an impact, preventing the fuel pump from running. Also pulled the small green wire from the TSZ (O7 on CE panel) back - this is the tach signal wire. I'll connect the MS3 medium current output for Tacho to this, and it will also control the other half of the FP relay, so if no tach signal from the computer (no signal from the crank sensor) then the fuel pump should not be running. I think there will be 1 more wire to run (MS3 #37) to control the Fuel Pump relay from the MS3 box - this should close the relay to run the pump for the programmed time before engine start. This might require all 3 control wires to have diodes installed so no weird "backflow" problems - I'll have to think about this.
Also ran most of the wires for the new EFI harness, just roughed in the lengths with extra on both ends. Of course, I realized later that I still have 9 more wires to stuff through the firewall boot hole! All my engine sensors to feed the MS3 box still to go, plus the small vacume hose for the MAP sensor in the MS3 box. I'll run a small section of hardline where it passes through the firewall boot to make sure it is not squeezed shut, causing incorrect MAP signals - that would be bad!
Also ran most of the wires for the new EFI harness, just roughed in the lengths with extra on both ends. Of course, I realized later that I still have 9 more wires to stuff through the firewall boot hole! All my engine sensors to feed the MS3 box still to go, plus the small vacume hose for the MAP sensor in the MS3 box. I'll run a small section of hardline where it passes through the firewall boot to make sure it is not squeezed shut, causing incorrect MAP signals - that would be bad!
12-19-2011, 10:18 PM
#59
Thread Starter
The crash sensor is supposed to open when the G impact is high enough. I hope I have it installed correctly to control the fuel pump relay, but after studying the current diagrams for hours today, I'm not so sure. I have to do some searching and find out the function of the #15, #31, and #31b lines that go into controlling the FP relay.
12-20-2011, 01:01 AM
#60
Administrator - "Tyson"
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The crash sensor is supposed to open when the G impact is high enough. I hope I have it installed correctly to control the fuel pump relay, but after studying the current diagrams for hours today, I'm not so sure. I have to do some searching and find out the function of the #15, #31, and #31b lines that go into controlling the FP relay.
He has the diagrams on how we wired up my car.
It looks a lot more complicated than it really is, but without the diagram I'm not going to try and explain it by memory and screw up anyone.