HEI + External coil in a 94'

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Josh
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HEI + External coil in a 94'

Post by Josh »

Well I finished my HEI and external coil swap. My car had an HEI from the previous owner but the job needed to be finished. I found that the 94' distributor is different than the others swap guides so I thought I would post my findings encase someone else with a 94' does not run into the same issue.

I used the guide according to the Club Protege swap guide an the V6 FAQ - http://mx-3.com/phpBB3/viewtopic.php?f=23&t=69006

I started with my dizzy cap and power tower - So I did not take a step by step photos for this but how I got it mounted in the center was I pulled the graphite electrode in the center (careful it has a spring on the base and you do not want to loose that), matched the bolt size of the power tower stud with a drill bit and drilled straight through the center of the cap. I then filed the head of the bolt in circumference so it would fit into the inside of the cap beneath the graphite electrode. I then notched the base of the power tower to fit the hump on the outside of the cap. I did have to take the drill and a grinding bit to the inside of the power tower to get the the proper distance I needed so it would sit properly. Lastly I cut about 1/8" or the thickness of the bolt head off of the top of the graphite electrode. It cuts like butter. Then I filed it (sand paper will work) so it had the dished effect it had out of the box.

And it was done.

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After some RTV and Plastidip on the power tower -

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So first off I found that the 94' 3 wire plug on the dizzy has a different color combination, though the colors still represent +, -, and the Tach signal.
Here is the breakdown of the dizzy.

Cap n rotor off
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The 3 screws removed and cover pulled off
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Then
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And finally the coil
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This is where it is different than the swap guide minus the 3 plug having the wires in a different order.
This is the photo that is provided in the swap tutorial, and it says to clip or unscrew this band.
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As you can tell the 94' does not have that at all.

What I found is that the prong that comes out of the coil needs to be eliminated. similar, but different.

From this -
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To this, a hacksaw blade made quick work of it , also you can see I cut off the tower just in the lower right hand side of the pic, filed it and globed on some RTV-
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So the female end of it I bent up inside a bit and filled it with RTV to prevent sparking.
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And then reassembly, you can kind of see in here that I bent it up in there a little bit.
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I then mounted my coil onto the frame rail directly and the HEI is mounted to a plate directly grounded to the frame.
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And all together.
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A couple pictures of the final assembly.
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I still have to tidy op some of the wiring, but I will probably finish that when I rebuild the motor early next year. Note: I used Dielectric on all connections, as well as I shrink wrapped everything and used connectors with shields to help keep the weather out. the HEI that was in there previously was corroded like crazy, and I had cleaned the terminals not 6 months ago.

End result after I figured out my hang up. Huge improvement, the car is sooo much smoother, this mod is completely worth it. I am excited to see how this effects the mileage. It is amazing how the idle has changed, it is nice and smooth all the way up to 7800. Very noticeable difference in driving.
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mazda915
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Re: HEI + External coil in a 94'

Post by mazda915 »

Great job on the mod looks great and yes its w huge improvement I wouldn't want to use the stock disty rather use the msd !!
1992 gs k8ze . 4 inch tip 2.5 cat , cold air intake ,corksport front and rear stut bars home made upper pillar bar , prosport gauges,megan racing 4 pts harnest, 10,000 K HID's , ksport suspension ,
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Josh
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Re: HEI + External coil in a 94'

Post by Josh »

Thanks, yeah the next step will be like a MSD 6AL or the digital SCI i have sitting around waiting to go onto the RS.
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Re: HEI + External coil in a 94'

Post by Josh »

Well I do not know if it is related but I am starting to have some rpm fluctuating issues. If the car is at full temp and mainly in traffic, my RPM's are bouncing all over the place, and it starts to pop and backfire. My thought is that the 1K resistor I used may be the wrong one? or perhaps with the car being a 94 I do not need the resistor? any thoughts?

I have also recently overheated and have been having coolant issues, found out that it was due to improperly sized radiator caps, new out of the box. But my other thought is that perhaps I have a coolant sensor going out. Any thoughts?
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Re: HEI + External coil in a 94'

Post by davmac »

Air in the coolant will cause surging or erratic idle. I'm not sure if your situation is surging idle or just a bouncing RPM gauge. If the idle is really bouncing around then I would guess it is directly related to the coolant issues you are having. I would pressure test the cooling system to find or confirm there are no leaks. Then purge air from the system and see if this cures your idle issue.
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Josh
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Re: HEI + External coil in a 94'

Post by Josh »

Ended up being a grounding issue. The alternator and coil were back feeding, threw on some 6 gauge ground wires and all the issues went away...
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Re: HEI + External coil in a 94'

Post by DeadMaker »

Maybe it's a stupid question but has anyone ever done this modification in bp engine?
Black Mazda Mx3 Rs 1997 B6DE
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Josh
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Re: HEI + External coil in a 94'

Post by Josh »

DeadMaker wrote:Maybe it's a stupid question but has anyone ever done this modification in bp engine?
There is no such thing as a stupid question, just stupid answers...

So the BP actually comes with an external coil unless you are running a later model. But yes, there is a write up somewhere for the internal coil B series. Tunes67 who is rarely on the forum now days did the HEI on his DOHC B6DE.
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DeadMaker
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Re: HEI + External coil in a 94'

Post by DeadMaker »

You mean the ignition coil like this right ?
http://www.ebay.com/itm/1991-93-Escort- ... 0474582608
So no reason to update..
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Josh
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Re: HEI + External coil in a 94'

Post by Josh »

Yep that is the coil.
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Re: HEI + External coil in a 94'

Post by Jforce »

So...why not just remove the stock coil?
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Josh
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Re: HEI + External coil in a 94'

Post by Josh »

not so easy with the 94' dizzy. If I had a 92-93 dizzy I could have. I would need to find something to take its place. I guess I could make a mold of it and create a polly foam replacement.
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