fujioko Reader
10/9/14 8:09 p.m.

So I have a '94 Miata with a Ford Festiva engine. The ignition system is custom made and uses a Saturn coilpack for spark. The hodgepodge ignition also uses some Saturn and some Chevy Caviler plug wires.

Anyway, its time to replace the wires and I think I want to try building a set to custom fit the car.

What is a decent brand for custom wires?

flexi New Reader
10/9/14 8:21 p.m.

If you want a custom set made, you can use Magnecor. They are surprisingly easy to get exactly what you need. I had a set made for custom Coils Near Plug setup for a miata. They were perfect, and they shipped them fast. Expect to pay ~80-100. If you want to build it yourself, you could order parts from them and crimp them. Hopefully others can chip in with lower $ solutions.

Kenny_McCormic PowerDork
10/9/14 8:26 p.m.

I'm pretty sure MSD and the like sell a kit just for this sort of thing.

Woody GRM+ Memberand MegaDork
10/9/14 8:39 p.m.

We used to make them all the time for boats. We used Accel kits.

Dusterbd13 SuperDork
10/9/14 8:48 p.m.

Ive run the msd cut to fit (buy them at flaps for 40 bucks). Good kits. Buy the v8 set and make two sets.

Ive also used the pro-comp 10.5 and accel 8.8 cut to fit sets. Don't know about longevity on those two brands. Msd is about 3 years and 30k.

Ditchdigger UltraDork
10/9/14 8:49 p.m.

Your local NAPA and Carquest will have, or can get you rolls of wire and all the terminals and boots you need. Most parts stores with a V8 dress up kit section will sell Accell or some other brand in a box for a V8.

These terminal crimpers suck

I really need to upgrade to a set of this style

We used to just make them for cars that didn't have wire sets available. Packards and other pre-war stuff, old jags...ect but after I made a set for an MG motor a few months ago and the boss saw how nice a custom cut and routed set of wires can look he decided that we should make them all.

fujioko Reader
10/9/14 8:52 p.m.

I played around with Accel kits back in the day. I'm a bit weary about their quality ...or it may have been I did a E36 M3ty job fabricating the wires.

Magnecor sounds promising. Need to get a price though.

Is MSD any good?

fujioko Reader
10/9/14 8:58 p.m.

I have access to a bunch of crimpers similar to the blue ones. The ones I can use are for professional grade coax but I wonder if they would work on plug wires...hmmm

pres589 UltraDork
10/9/14 9:14 p.m.

I bought a crimper like the blue jobs for $50 at an auto parts store. I bet you could do better shopping online. MSD cable is pretty easy to work with. I sourced terminals and boots from one of the big box autoparts stores locally. No big deal.

Nick_Comstock PowerDork
10/9/14 10:17 p.m.

I used a V8 8.8MM MSD kit when I did the ignition upgrades on my last E21. Easy enough to work with but didn't keep it long enough to know about longevity.

ncjay Dork
10/10/14 2:01 a.m.

All my cars have custom plug wires made by me using Accel kits. The best crimper I have used is from MSD. http://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=msd%20wire%20crimpers I've also found that when putting on spark plug boots, I've gotten awesome results using dish soap.

MadScientistMatt UberDork
10/10/14 7:30 a.m.

We used Magnecor on our projects around the shop and have been quite pleased with them.

patgizz PowerDork
10/10/14 8:40 a.m.

i just looked at your pic. buy a cut-it-yourself chevy v8 hei kit with straight plug ends and you'll get 2 sets out of it.

the gm coil packs you have use an hei end and you can use any straight boots.

Rob_Mopar SuperDork
10/10/14 10:15 a.m.

Avoid the Accel Super Stock series. They are the low-end ones.

I've had good luck with the Accel 300+ wires, MSD Super Conductor, Pertronix, and Taylor. Don't use the braided stainless ones.

If you don't want to buy the crimpers, the MSD Super Conductor kits come with dies you can use in a bench vice to crimp the ends.

Leafy Reader
10/10/14 10:46 a.m.

Holy crap the B6 SOHC miata is alive, the guy who made it like dropped of the face of the world shortly after he finished it. He also made like a metro powered one or something. Is this you?

oldopelguy SuperDork
10/10/14 11:27 a.m.

I'd love a fuel economy and performance report on that car. I've thought about that dirvetrain combination for my Opels dozens of times over the years.

Rusnak_322 Dork
10/10/14 1:17 p.m.

I am friends with the owner of this company - https://www.customwiresets.com/customize.php

He sells to NHRA Top Fuel Dragster teams such as Tony Schumacher.

fujioko Reader
10/10/14 7:04 p.m.

Thanks for all the responses!

I took a trip to the very unhelpful auto parts store during lunch to see what was available. They has MSD kits for $64.00 but the boxes were security strapped and I couldn't get a look inside. I was on my way out the door when a semi helpful parts chick mentioned they had store brand universal kits for $14.00. sparked my interest so I had a look....

Anyway, these store brand wires are probably crap but I figured I could rig up a set to find the right lengths and order a custom set from Magnacor.

Now for the rest of the story..

The oscilloscope was picking up a lot of RF/EMF with the old wires. This random energy was finding it way into the Megasquirt and was causing an offset in the AFR ratio. The dashboard gauge displayed one number and the megasquirt displayed a different number. I went through the whole troubleshooting thing and this is when I discovered the plug wires were NFG

Store brand wires for $14.00 will work for now but are not a long term solution. I borrowed the crimpers from work, they are made for coax but work great on the plug wires. I used two size crimpers, one to do the initial crimp and a second to finish the crimp. A little more work, but they were free to use.

this is actually a very impressive crimp.... especially for using the wrong tool.

New wires routed and looking tidy.

The oscilloscope shows a serious improvement

In response to leafy,

The car is alive and well and yes I'm the guy that built the three cylinder Miata years ago. The three cylinder car was sold and has fallen off the edge of the earth, but the B3 continues to make progress. The B3 build thread is still active on both forums The GRM link is https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/1994-miata-mpg-project-b3-stealth-mk-ii/61007/page1/

Thanks again everybody for the helpful suggestions.

Kenny_McCormic PowerDork
10/10/14 7:17 p.m.

What are you probing with the scope? Seems like a useful diagnostic procedure now that I have a highly portable one.

fujioko Reader
10/10/14 7:37 p.m.

In reply to Kenny_McCormic:

Hi 'ya kenny,

I was initially probing the IAT sensor (intake air temp) that was when I discovered the oscilloscope would go crazy near the coil pack.

In the first photo I'm basically doing a free air sample of the energy near the wideband sensor. Not very scientific because their will always be some energy regardless of the condition of the plug wires.

The second photo the probe was in the same location and the difference is obvious.

Unfortunately this method is not exactly reliable because the probe wasn't actually connected to anything, however the Scope is displaying a large flyback signal and its not connected to anything.. I figured something was wrong with the wires.

Storz Dork
10/11/14 8:10 a.m.
Woody wrote: We used to make them all the time for boats. We used Accel kits.

Yep. Ran the same set on my 18' jet with a BBF

Derick Freese
Derick Freese UltraDork
10/11/14 11:48 a.m.

MMM, old Tek.

Dusterbd13 SuperDork
10/11/14 2:17 p.m.

What was the part number and how many wires did you wind up with?

fujioko Reader
10/11/14 4:10 p.m.
Dusterbd13 wrote: What was the part number and how many wires did you wind up with?

The part number is 1600. You get eight plug wires plus a coil wire. The spark plug boots were already crimped. The kit comes with conventional distributor and HEI type terminals.

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