'70 Dart 392 Project; what direction?

[DionR]

Does that engine have a harness? My coils have 3 pins on them, but only two wires going to them. I don't know what the extra pin is for. Since I cut down a factory harness, I really never paid any attention to it until now. Rock auto shows the same part number for coils between non-vvt and vvt engines. I always thought the coils were the same because when doing an eagle head swap, I've always read the only parts needed were heads/rockers/pushrods, valve covers and intake. Nothing about coils.

It did come with a harness and sure enough you are right, only 2 wires. In my defense, I pulled the harness off when I was getting it out of the bed of my truck and only looked at a coil earlier.

Looks like pins 1 and 2 are the ones used.

 

[racerjoe]

It did come with a harness and sure enough you are right, only 2 wires. In my defense, I pulled the harness off when I was getting it out of the bed of my truck and only looked at a coil earlier.

Looks like pins 1 and 2 are the ones used.

View attachment 1716262077

There you go. Sooner or later we're going to be experts on this platform.

 

[208Dart]

The coils only need a power wire and the signal wire. It's like having 8 old school canister coils. You may want to confirm their harness isn't made to be used with their smart coils.

Just got this from Holley regarding their harness. They suggested using capacitors to plug into the harness to reduce any "noise". Looks like each bank shares a power source and they have individual signal wires.

 

[racerjoe]

Just got this from Holley regarding their harness. They suggested using capacitors to plug into the harness to reduce any "noise". Looks like each bank shares a power source and they have individual signal wires.

View attachment 1716262098

I assume the other side of the capacitor is grounded. I believe the factory harness had something like this. I trashed them. It's probably less about the coils seeing noise and more about the coils creating noise. The only electronic device on my car is the ECU and I've never had any weird electrical problems. Perhaps the factory cars have electronics that may be sensitive the switching of the injectors and coils.

 

[DionR]

I assume the other side of the capacitor is grounded. I believe the factory harness had something like this.

Yep.

Bolted to the back of the cylinder head every time I have looked for them.

 

[208Dart]

Ac lines and coolant lines are 98% done. Just need one more #10 90* for underdash and a few more hose clamps and need two radiator hoses and coolant system hardware is done.

Rest of my wiring connectors and hardware should be here by Tuesday so next week I’ll be starting on the MS wiring.

 

[208Dart]

Update on Connectors. The Ballenger connectors do not work for cam/crank sensors. I stopped by Oreilly's and they pulled a Standard Ignition PN of S2916 for the pigtail/connector.

Found them on Rock Auto for $5.99/piece.

Holley harness showed up today and connects perfectly to the ignition coils.

Won't have my final AC connector till end of week/next week.

Feels like that Johnny Cash song.... one piece at a time!

Mike

 

[208Dart]

Alright need some input. Got my ECU mounted in the glovebox and output bundles through under the dash. Like how it turned out.

Trying to decide on where to mount my quadspark modules. Both on one side or split them one side then the other? Any potential issues with either?

Also I couldn’t resist. Bought a battery and ran a ground wire to my starter solenoid and bumped the key… got a half crank from it before I let off. Least I did that part right!

 

[208Dart]

Don't know if you have seen this site before, but maybe it will help some?

Mopar Connection Repair Kit

Dude thank you again for the link. Found pinouts on there for cam/crank sensors as well as injectors!

 

[racerjoe]

Alright need some input. Got my ECU mounted in the glovebox and output bundles through under the dash. Like how it turned out.

Trying to decide on where to mount my quadspark modules. Both on one side or split them one side then the other? Any potential issues with either?

Also I couldn’t resist. Bought a battery and ran a ground wire to my starter solenoid and bumped the key… got a half crank from it before I let off. Least I did that part right!

View attachment 1716264301

View attachment 1716264302

View attachment 1716264303

I mounted my quadsparks under the dash.

As for how to arrange them, I used my the same methodology as I did for the power. Each bank has its own power, and now each bank has its own quadspark. That way if something fails, I can quickly identify it since only have the engine is running.

 

[208Dart]

More progress on the engine side. Got probably 80% of the wires ran on this side. Haven’t ran any grounds other than the sensor grounds to the one bulk head. Crank sensor connector won’t be here till Monday along with my second bulkhead and bulkhead plates. Going to run separate locations for either bulkhead. If I had to do this over again I would’ve laid out everything EARLY on in the build to have a cleaner firewall but I’m not that disappointed with how everything is going to come together.
FYI this is my first time using weatherpak style connectors and they’re freaking amazing. So much better than tradition crimp and heat shrink connectors. Going to mount each quad spark on opposite inner fenders as well since I’m about out of room under the dash with heater hoses and AC stuff.

Still have to make up the fuel injector harness, IAT sensor (need an intake tube), crank sensor, and some grounds in the engine bay as well as fans.

Got my painless wiring diagram out and have some unused fuses that should work for my needs as well.

Most the wires should be fairly well hidden under the engine covers as well.

Designating a bit of time this coming week to finish wiring. Hopefully I’m not missing too many components.

Still need to sort out radiator hoses, overflow bottle, and an air intake with IAT sensor location and obviously wire loom everything once it’s all finalized.

 

[208Dart]

Engine bay wiring is 99% done far as I can tell. Still have to wire underdash to bulkheads and get my relays and battery grounds/supply ran as well.


Orders a 45* 4” intake bend off Amazon, cut it down and stuck a K&N filter on the end. Really like the way it looks. Need to TIG in my AIT sensor bung and connect those wires, fan wires, and my knock sensor wires but then she’s done on this side. Added oil and removed the tape off the intake ports and bolted the intake in place and trimmed my throttle cable. I ended up adding about 1/4” of bend into my throttle pedal rod and now I have complete throttle opening.

Gave it a 1 second crank after adding oil and this thing sounds mean even at crank RPM

Once I get it started and verify wiring is good I’ll wire loom and tape everything up! Hoping for first crank next week, out of town Friday through Sunday this weekend

 

[Kiddart1]

these gen 3's just look so good in older cars!!! I love mine!!

 

[208Dart]

Well damn I’m close!
Lot done today. Short of connecting the laptop and confirming sensors and calibrating O2 sensors I believe im done with the megasquirt wiring. Also got my AC and coolant lines connected and clamped under the dash, got the first two vent hoses ran to the defrost vents and tied up a ton of wiring. Got all my relays wired and grounds ran. Still waiting on a lower radiator hose reducing coupler to show up so I can fill coolant, then I need to fill trans/rear diff, power steering, coolant. And run through the initial setup on megasquirt. Hope to crank it Monday (open headers of course).

Fabbed up a redneck gauge holder on the dash for now. Not permanent but had to go somewhere with the O2 gauge.


It’s exciting just to see the AFR gauge go live and hear the fuel pump do its initial 2 second prime when the key goes to ON.

Happy 4th everyone.

 

[racerjoe]

Well damn I’m close!
Lot done today. Short of connecting the laptop and confirming sensors and calibrating O2 sensors I believe im done with the megasquirt wiring. Also got my AC and coolant lines connected and clamped under the dash, got the first two vent hoses ran to the defrost vents and tied up a ton of wiring. Got all my relays wired and grounds ran. Still waiting on a lower radiator hose reducing coupler to show up so I can fill coolant, then I need to fill trans/rear diff, power steering, coolant. And run through the initial setup on megasquirt. Hope to crank it Monday (open headers of course).

Fabbed up a redneck gauge holder on the dash for now. Not permanent but had to go somewhere with the O2 gauge.


It’s exciting just to see the AFR gauge go live and hear the fuel pump do its initial 2 second prime when the key goes to ON.

Happy 4th everyone.

View attachment 1716271839

I ran mine a bit with open headers but could do any tuning. The O2 was too close to the end of the pipe and would read super lean when it was actually very fat!
I’d recommend going through all the injector and coil tests just to make sure you don’t have any wiring errors. It doesn’t take long to go through the firing order for each of them.

 

[208Dart]

I ran mine a bit with open headers but could do any tuning. The O2 was too close to the end of the pipe and would read super lean when it was actually very fat!
I’d recommend going through all the injector and coil tests just to make sure you don’t have any wiring errors. It doesn’t take long to go through the firing order for each of them.

Good to know! I have some 10” long collector pipes I was going to bolt in but doubt that’ll be enough. if I had too I could clamp in mufflers temporarily until I can move the car to get exhaust built.

 

[racerjoe]

Good to know! I have some 10” long collector pipes I was going to bolt in but doubt that’ll be enough. if I had too I could clamp in mufflers temporarily until I can move the car to get exhaust built.

Mine is in the exhaust collector about 6” from the end of the pipe. I didn’t use the TTI location since they have the bung on the outside of the header collector. I just didn’t like the idea of being able to see an O2 sensor from the side of the car. You may be ok if you use the header collector and an extension. I’m sure it also depends on your cam profile.

 

[208Dart]

Well I'm ready to start the engine I believe, but after going through all the sensor calibrations and fuel/ignition settings, first time I cranked the engine tunerstudio shut down. Its apparent that my "12v switched" wires I used for the ECU/FUEL/02 sensor/fan relays go dead when the engine cranks.

Anybody have a good source off the top of their head for a 12V switched source that doesn't go dead when the engine cranks?

Thanks in advance!

Mike

 

[DionR]

Well I'm ready to start the engine I believe, but after going through all the sensor calibrations and fuel/ignition settings, first time I cranked the engine tunerstudio shut down. Its apparent that my "12v switched" wires I used for the ECU/FUEL/02 sensor/fan relays go dead when the engine cranks.

Anybody have a good source off the top of their head for a 12V switched source that doesn't go dead when the engine cranks?

Thanks in advance!

Mike

What ignition switch are you using?

If you are using the stock switch, there is a brown wire that goes hot during cranking but is cold during run. There is also a blue wire that should be hot during run and cold during crank. You could tie these together, but my understanding of the new Hemi's is that when the switch goes from start to run there is point where both wires are cold and the PCM doesn't like it. But you have Megasquirt so no idea if they have the same issue.

One option would be to add a push button start. Then everything is hot at all times but the starter can be engaged only when the button is pushed.

 

[208Dart]

What ignition switch are you using?

If you are using the stock switch, there is a brown wire that goes hot during cranking but is cold during run. There is also a blue wire that should be hot during run and cold during crank. You could tie these together, but my understanding of the new Hemi's is that when the switch goes from start to run there is point where both wires are cold and the PCM doesn't like it. But you have Megasquirt so no idea if they have the same issue.

One option would be to add a push button start. Then everything is hot at all times but the starter can be engaged only when the button is pushed.

Using factory ignition switch. Little forum search jives with what you’re saying. Need to jumper ignition 1 and 2 off the ignition switch to power the relays. Hopefully tomorrow is the day…. Fingers crossed

Mike

 

[208Dart]

Well I pulled wire from the brown column balast resistor wire and tied it into the 12V switched wire to the relays but now the O2 sensor relay is on all the time. Gotta dig a little more...

Dude thank you again for the link. Found pinouts on there for cam/crank sensors as well as injectors!

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View attachment 1716264401

View attachment 1716264402

Well I tied into my brown "ignition balast" wire coming from the column, it's registering 12V during cranking. I spliced it into the previous 12V switched wires I had going to the relays, but now the o2 Sensor relay is on all the time. Gotta dig into that more.

I got my fuel pressure set at 58-60psi, had an injector Oring leaking so made a parts run and got that fixed. No leaks on fuel system.

My current issue is I'm not registering RPM... I'm wondering if the diagram above is looking at the sensor connector and not the pigtail connector. That's the only thing I could think of why it wouldn't be registering RPM...

The saga continues...

MIke

 

[racerjoe]

Well I pulled wire from the brown column balast resistor wire and tied it into the 12V switched wire to the relays but now the O2 sensor relay is on all the time. Gotta dig a little more...


Well I tied into my brown "ignition balast" wire coming from the column, it's registering 12V during cranking. I spliced it into the previous 12V switched wires I had going to the relays, but now the o2 Sensor relay is on all the time. Gotta dig into that more.

I got my fuel pressure set at 58-60psi, had an injector Oring leaking so made a parts run and got that fixed. No leaks on fuel system.

My current issue is I'm not registering RPM... I'm wondering if the diagram above is looking at the sensor connector and not the pigtail connector. That's the only thing I could think of why it wouldn't be registering RPM...

The saga continues...

MIke

Make sure you have your crank signal setting correct in tuner studio. I just copied what DIY Autotune shows on their webpage.

 

[208Dart]

Make sure you have your crank signal setting correct in tuner studio. I just copied what DIY Autotune shows on their webpage.

I did the same. Toothed wheel/2 missing teeth and the 60 tooth….etc will double check but I’m pretty confident that’s it.

I pulled my sensor harness and I’m getting 5v reference, ground, and 2v on the signal pin. Same values on the Cam sensor. Going to try and reverse the signal and 5v reference wires tomorrow unless there’s a way to test sensor with it not installed in the engine?

I’d really like to find out how to display specific sensor values in Tuner studio. Can’t find my oil pressure value nor the ckp/cmp values….

 

[Dantra]

I'm sure you know about this.. But just in case. Wiring – MyMopar

I printed out large (very large) posters of all of my wiring diagrams on a plotter and hung them on the wall. Really helped having a quick reference.

 

[racerjoe]

I did the same. Toothed wheel/2 missing teeth and the 60 tooth….etc will double check but I’m pretty confident that’s it.

I pulled my sensor harness and I’m getting 5v reference, ground, and 2v on the signal pin. Same values on the Cam sensor. Going to try and reverse the signal and 5v reference wires tomorrow unless there’s a way to test sensor with it not installed in the engine?

I’d really like to find out how to display specific sensor values in Tuner studio. Can’t find my oil pressure value nor the ckp/cmp values….

Use the "Diagnostics and High Speed Loggers" tab at the top to view the cam and crank signals.

These are my settings, which are likely the same as yours if you copied the DIY site.

If you used a generic analog input for the oil pressure, you need to figure out what input you used and scale the sensor. Under advanced Engine tab, select Generic Sensor inputs. Choose the source, name it whatever you want, then enter the scale. On this same section, under tools, there is a sensor scaling tool if needed.