THe NAC Lots-O-BFG KO2 Thread

Re: THe NAC Lots-O-Post Thread

Ignition and lights is pretty much the only reason at this point.

There really won't be much left of the actual XJ harness. Things I can think of:

- Headlights
- Taillights
- Fuse panel
- Underhood fuse box
- Starter signal wire
- Horn?
- Alternator (unless I switch to an internally regulated, single wire GM unit)

Fuel pump gets controlled by MS. Pretty sure MS can be programmed to run the electric fans when the engine hits a certain temp as well.

In all honesty, I really don't need that much. It would probably save a weekend or two from building a harness from scratch. I certainly don't need all the circuitry grafted into a Painless harness. I definitely want to get rid of the stock ECM if I can. I think the only thing that would require me to keep it is if I run the XJ alternator (voltage regulated by the ECM).

So as a bare minimum to get it running, all I'd really need is a way to activate the starter :laugh:.

Would anybody be interested in buying it? I'd probably just ask like $50 considering the 2 weekends I have into it.

EDIT: Actually, I just realized I snipped the injector wires off :laugh:. Not sure if anyone wants to actually deal with that.
 
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Re: THe NAC Lots-O-Post Thread

So I think as far as wiring goes, I'm probably going to chop down my 4.0 harness again just so I have something for NAC-fest.

After that, I think I'm going to build a new harness that is run correctly using color coded wires and some good quality (read weatherproof) connectors/relays, etc.

I've thought about getting a painless harness, but for $400 I think I could do a better job. I'll just be investing my own time.

we were talking about this painless harness for my friend's brothers LT1 swapped RX7. it makes it WAY easier, and you're already setup for racing with the kill switches. cut out everything engine related from the jeep harness, keep the rest. then use the painless harness + plate & switches it comes with.. flip on fuel, flip on ignition, push to start. done.
 
Re: THe NAC Lots-O-Post Thread

I don't mind doing wiring in all honesty, it's just I have a feeling I'm going to be in a time crunch again to get it done for NACfest.

I'd rather slap together whatever I have in order to make it there, then when I get back pull it apart and rewire the whole thing.

I don't mind spending a weekend or two building a wire harness. Hell I could even do that during weeknights inside the garage. Not like it's that labor intensive.
 
Re: THe NAC Lots-O-Post Thread

Why would you run the XJ alternator? Does it even bolt on to your motor?

I'd think there'd be some kind of even more badass one that came stock on a 440, that's internally regulated/one-wire. Or just use a simple standalone regulator...that's all we did on the Cummins Bronco.
 
Re: THe NAC Lots-O-Post Thread


Neither of you are cool for posting those, unless those are your vehicles.

"Yeah, well the Dodge Sprinter Van will outrun a Ford Pinto on the drag strip and I've got that engine in my totally not the same vehicle!"

It's kinda like elementary school all over again. :laugh3:
 
Re: THe NAC Lots-O-Post Thread

I don't mind doing wiring in all honesty, it's just I have a feeling I'm going to be in a time crunch again to get it done for NACfest.

I'd rather slap together whatever I have in order to make it there, then when I get back pull it apart and rewire the whole thing.

I don't mind spending a weekend or two building a wire harness. Hell I could even do that during weeknights inside the garage. Not like it's that labor intensive.

it is a fairly simple motor electronically, but you dont want to DIAF while wheeling. i wouldnt want to slap it together only to have to take it apart again.. i'd at least slap it together with some glue and tape so it lasts until you get the kinks out and you buy the "really cool part you really want but dont necessarily 100% need" a year later
 
Re: THe NAC Lots-O-Post Thread

Yeah, this little guy:

1V1081.jpg


Costs 9 bucks and works fine with the alternators that came on pretty much every Chrysler thing from 1969 to 1991.
 
Re: THe NAC Lots-O-Post Thread

Why would you run the XJ alternator? Does it even bolt on to your motor?

I'd think there'd be some kind of even more badass one that came stock on a 440, that's internally regulated/one-wire. Or just use a simple standalone regulator...that's all we did on the Cummins Bronco.

I haven't bothered to look, and I'm not sure I want to run V-belts.

Granted, it would save me probably like $150.

I could also swap over to a p-pump and use stock bracketry and sell my current PSC pump.

Hmm...

Neither of you are cool for posting those, unless those are your vehicles.

"Yeah, well the Dodge Sprinter Van will outrun a Ford Pinto on the drag strip and I've got that engine in my totally not the same vehicle!"

It's kinda like elementary school all over again. :laugh3:

We're just poking at each other.

God you're like a 90 year old.

Yeah, this little guy:

1V1081.jpg


Costs 9 bucks and works fine with the alternators that came on pretty much every Chrysler thing from 1969 to 1991.

If those are what I'm thinking of, my father always used to keep one in any vehicle that had one because they regularly failed.
 
Re: THe NAC Lots-O-Post Thread

it is a fairly simple motor electronically, but you dont want to DIAF while wheeling. i wouldnt want to slap it together only to have to take it apart again.. i'd at least slap it together with some glue and tape so it lasts until you get the kinks out and you buy the "really cool part you really want but dont necessarily 100% need" a year later

Why would I DIAF?

I'm not talking glue/tape the XJ harness. I just meant chopping off what I don't need (aka no dead end live wires).

After listing out what I ACTUALLY need to get the thing running, I'll probably try to spend the time up front to build the wiring harness I want.
 
Re: THe NAC Lots-O-Post Thread

Ignition and lights is pretty much the only reason at this point.

There really won't be much left of the actual XJ harness. Things I can think of:

- Headlights
- Taillights
- Fuse panel
- Underhood fuse box
- Starter signal wire
- Horn?
- Alternator (unless I switch to an internally regulated, single wire GM unit)

Fuel pump gets controlled by MS. Pretty sure MS can be programmed to run the electric fans when the engine hits a certain temp as well.

In all honesty, I really don't need that much. It would probably save a weekend or two from building a harness from scratch. I certainly don't need all the circuitry grafted into a Painless harness. I definitely want to get rid of the stock ECM if I can. I think the only thing that would require me to keep it is if I run the XJ alternator (voltage regulated by the ECM).

So as a bare minimum to get it running, all I'd really need is a way to activate the starter :laugh:.

Would anybody be interested in buying it? I'd probably just ask like $50 considering the 2 weekends I have into it.

EDIT: Actually, I just realized I snipped the injector wires off :laugh:. Not sure if anyone wants to actually deal with that.
go for it, you're an EE, you can figure that shit out easy. Hell it is easier to build a harness than it is to figure out what the hell is going on in a stock one imo, they spliced like crack addled chimps and ran things all bass ackwards to save money. Especially for the relays in the lighting circuits.

Building an alt regulator should not be hard, even if you don't just buy a prebuilt. All it does is PWM the field coil (one side to 12v, the other to a mosfet ground side switch, just a regular n channel mosfet driver basically) till it sees ~14 volts at the battery. Simple closed loop control system. If you want to get real fancy, put a temp sensor under the battery and limit charge current above x degrees.
 
Re: THe NAC Lots-O-Post Thread

go for it, you're an EE, you can figure that shit out easy. Hell it is easier to build a harness than it is to figure out what the hell is going on in a stock one imo, they spliced like crack addled chimps and ran things all bass ackwards to save money. Especially for the relays in the lighting circuits.

Building an alt regulator should not be hard, even if you don't just buy a prebuilt. All it does is PWM the field coil (one side to 12v, the other to a mosfet ground side switch, just a regular n channel mosfet driver basically) till it sees ~14 volts at the battery. Simple closed loop control system. If you want to get real fancy, put a temp sensor under the battery and limit charge current above x degrees.

My big problem is that I'll be anal retentive with the wiring, and I'm just not sure whether or not I'll have the time before NACfest to get it all done.

I'll probably have to wait and see when the time comes.
 
Re: THe NAC Lots-O-Post Thread

Chris I just saw your thread on PBB.

Screw the naysayers, I'm going to run MS anyway.

i think its 100% doable. mount the MS in a sealed box, seal where the wires go in with some silicone, mount the whole thing somewhere relatively dry (under the dash like one dude said) with a nice rubber grommet to avoid vibes.
 
Re: THe NAC Lots-O-Post Thread

Yeah I remember reading they don't produce much heat at all either.

But I'm just going to do like I said. Mount a splash shield to keep the heavy shit off of it. I'm sure it will be ok. I'll throw some dielectric grease on those connectors too.
 
Re: THe NAC Lots-O-Post Thread

Yeah I remember reading they don't produce much heat at all either.

But I'm just going to do like I said. Mount a splash shield to keep the heavy shit off of it. I'm sure it will be ok. I'll throw some dielectric grease on those connectors too.

i dont see it being a huge issue. look at the shit we throw at stock ECUs- how often are they failing?
 
Re: THe NAC Lots-O-Post Thread

Yeah I remember reading they don't produce much heat at all either.

But I'm just going to do like I said. Mount a splash shield to keep the heavy shit off of it. I'm sure it will be ok. I'll throw some dielectric grease on those connectors too.

The bulk of any heat buildup I'll have is from firing the fuel injectors...yours will probably run cooler as I think your duty cycle will be lower; mine'll be grounding an injector 400 times per second at redline. :laugh:

With high impedance injectors I don't forsee it being a problem though...and even though it'll be controlling ignition as well, it's all logic-level signals to the individual coils.

I'm more worried about the connection of the MS3 daughter board to the V3.0 chip socket (does the v3.57 board use this too? I think so...), and the ribbon cable connection from the MS3 board to the MS3x expansion doober. I can probably find a way to glue 'em or something.
 
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