So, I am going megasquirt....

In reply to Knurled:

There's no good place to put it on the core support. I'll be running megasquirt control of ignition. I'll attach a picture of the current engine bay and harness routing (this is all coming out in a few days for a rewire and the megasquirt ) to give you guys are better idea of what we are working with. Harness layout will be very similar, as well as the visual package.

Understood... Just throwing out an example, mind you.

I wonder if you could use braided AN line as a shield for those two wires. Should be able to fit them through AN6 easily, ground the engine end, and be done with it?

Or would it work to use the shielded wire like we discussed earlier? Or too much noise?

[URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20160530_100825_zpsavmxvyie.jpg.html][/URL] [URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20160530_100800_zpsaunbct5o.jpg.html][/URL] [URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20160530_100752_zpstj1a03th.jpg.html][/URL] [URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20160530_100815_zpsxoywskco.jpg.html][/URL]

Dusterbd13 wrote: Also, I'm seeing reference to two different codes. A bollings and grippo, and another. Which one do I want?

You'll want the MS2/Extra code here. It's the only code version for MS2 that offers A/C idle up.

For a distributor, keep the MSD box. While the MS2 can control the timing, having the MSD box will give you significantly more spark energy at high RPM.

In reply to MadScientistMatt:

OK. I'm ready to order when you are.

And you mean to keep msd in addition to the hei module and coil, correct?

Dusterbd13 wrote: In reply to MadScientistMatt: OK. I'm ready to order when you are. And you mean to keep msd in addition to the hei module and coil, correct?

Correct.

It should all land next week sometime.

Wow, that wasn't cheap. (At least not to me.) But if we get the same success in my duster that yall are enjoying, it's money very well spent.

You will be assimilated. Resistance is futile.

Join the dark side. We have cookies.

I have some wire braid you can slip over wires as shielding. You just need to solder a ground to it to work. Lmk kandpperformance at gmail dot com

You have mail Paul

Now that I have the parts in my grubby hands, next stupid question : does the case need to be mounted in such a way as to make it grounded? Or should I add rubber feet to insulate it from vibration and ground?

Mine is ziptied to some plastic piece of the dashboard. I had overheating issues with it on the trans tunnel.

So, again, I'm over thinking things again?

Mine's mounted to the fiberglass map pocket under the dash on my 924.

Here it is during mockup:

You'll want to keep it away from excessive heat and water, but mostly you'll want to make sure you can access it to configure wiring, connect tuning cable, etc.

Dusterbd13 wrote: So, again, I'm over thinking things again?

Yep. A little bit.

Rubber mounts won't hurt, especially on cars that are prone to lots of vibration, but factory ECUs aren't mounted in rubber.

Focus on mounting it in a good spot that works best for you for service, etc. and get the wiring run.

The wiring is what makes or breaks a lot of builds.

Is there a good reason not to leave the tuning cable permanently mounted and route it like an obd port?

It will stress the connection on the board unless you support the weight of the cable.

Mind you, I do this too, leaving the cable just hanging by the DB9. But I know that it's bad and if it cracks the board, I have nobody to blame but myself.

After something like 6 years on a 1.01 board, that I bought used on the GRM classifieds, I never had a problem. What killed it was a voltage spike after the positive battery cable came off after some wheels (bought on GRM classifieds) bumped it off of the battery.

The GRM Classifieds is the cause of and solution to all of life's problems.

Ok, fair enough. Is,any mounting orientation fair game, or horizontal only?

Not that I can think of. Keep the cable run as short as possible, protected from damage and cover the end when not in use and it should be fine.

No orientation issues, it's all solid state and it doesn't care about directionality.

Knurled mentioned a voltage spike from a battery coming unhooked. Should I do away with the remote battery kill switch? Holdover from drag car days, but nice to have since the battery is buried.

In reply to Dusterbd13:

I think you're ok as long as it kills all of the power at the same time, otherwise it could cause that kind of spike as the power tries to find another path.

GOOD question. If you have a kill switch, connect the alternator's power lead (the one with the stud/nut connection) DIRECTLY to the battery.

In this way, when you hit the kill switch, the car will not stay running off of the alternator. That would rather defeat the purpose of having a kill switch.

My personal issue was related to the voltage spikes created when the battery is removed from the system. Automotive electrical systems are very, very noisy, and the battery helps damp that noise. If the battery gets disconnected, you get massive voltage spikes in both directions. This is bad, and is also bad for electronics.

What killed that unit, incidentally, was not the FIRST time the battery came disconnected while driving. It was a not-uncommon occurrence and I could easily reach back and wiggle the cable when "battery disconnected" symptoms arose (things like "momentary voltage dip when brakes applied" kind of things).

It wasn't the FIRST time it happened, in other words... it was the LAST time! Because it didn't happen anymore after that, it was FINAL.

I shoulda made the guy who used cheap battery cable ends pay for my new computer! Oh wait, i did... crap!

Thanks guys. Main 4 gauge harness feed comes from one side, and the 6 gauge charge goes directly from the alternator to positive battery post. Kills the entire car when I flip the switch.

Only thing that don't die instantly are that the stereo amps go directly to battery positive and negative. Also, there's a body mounted ground at the battery, and a ground from battery to starter mounting bolt.

I know we're into the ludicrous end of things here. Alternator is 140 amp, battery in the trunk, etc. Mostly, I always tend to run severe and total nuclear overkill on power and ground systems to pretty much future proof the cars.

Next question: with battery being directly grounded to engine, I just use the opposite corner for megasquirt ground to reduce offset errors, correct?