Mount coils directly to the plugs

[sen2two]

so I am not using a traditional coil on plug piece. I am using an MSD SS coil on a my 12a for direct fire set up using HEI igniters (TFIDFIS). I want to mount my coils directly to my spark plug. But the only straight boots I can find are for coil to wire.

Anyone know where I can find a coil boot that will let me go straight from coil to spark plug?

[RETed]

I don't know if this is a good idea...

Electronics do NOT like:
1) Heat
2) Vibration

Putting the coil on the spark plug just increased both.

The only way to combat this physics is just reduce the mass...
This is why Coil-On-Plug designs (for OEM) use a pretty small coil.
So, you're just reduced your coil performance just to get rid of the spark plug wire???

I'd rather run a honking, big coil and run traditional spark plug wires...

Unless you're RICE RACING with a LOT of money!


-Ted

[sen2two]

I don't see how they will see any more heat or vibration than mounting them on the strut tower as is normally done. Or on the motor which is often done.

Realistically the difference is a few inches, so the heat problem is a non-issue. Since these coils will be mounted on a plate which is attached to the motor. There will be no movement difference between the plugs and the coils.

After heavy searching, I have come to the conclusion that they do not make a boot for this. So I guess I will be making my own.

[RETed]

Let me get this straight...

You want to mount your coils onto something other than directly onto the engine / spark plugs?

You don't want to use spark plug wires?

Does that sum everything up?
Did I miss anything?


-Ted

[chibikougan]

http://www.rx7club.com/3rd-generatio...-packs-864760/


I believe you have to cut down the spark plug also.


Need a trigger and something to drive 4 2 wire coils.


Build a custom mount.


Good Luck

[sen2two]

Originally Posted by RETed

Let me get this straight...

You want to mount your coils onto something other than directly onto the engine / spark plugs?

You don't want to use spark plug wires?

Does that sum everything up?
Did I miss anything?


-Ted

I just tried to draw it up in SolidWorks so I can post a 3d rendering, but of course the program is giving me an error. pictures are worth a thousand words, and even more in this scenario.


What I am trying to do is, make a mount that will be attached to the engine. This mount will hold the coils/igniters directly in front of the spark plugs also acting as a heat sink. The spark plugs will be connected directly to the coils through a boot that I will make, since I do not believe they make this type of boot.

Please note that this is not for a fuel injection motor. These are 2 Blaster SS coils (8207) using HEI igniters, with a 85 distributor (TFIDFIS). Using with no trailing ignition at all.

[chibikougan]

Did you ask just to tell everyone what you are going to do?

Seems like you have it figured out.

Good luck

[sen2two]

Originally Posted by chibikougan

Did you ask just to tell everyone what you are going to do?

Seems like you have it figured out.

Good luck

I posted thinking that maybe somebody would know where to get one of the boots to mount a coil to a plug. I never asked a question on how to do it or if it would work. Only where to get the part.

[sen2two]

Thank you, but none of those will work. Those are all factory replacement parts. I already started to make my own.

[chibikougan]

Originally Posted by sen2two

Thank you, but none of those will work. Those are all factory replacement parts. I already started to make my own.

So the direct 90° angled one made for your coils are factory replacement..?????


Good luck...

[sen2two]

Originally Posted by chibikougan

So the direct 90° angled one made for your coils are factory replacement..?????


Good luck...

If you are referring to the MSD part 3331, that is for coil to plug wire. That will not work from coil to spark plug.

[chibikougan]

Nope.

You got it figured


Edit: I am excited to see what you have come up with. Get on it

[C. Ludwig]

Magnecore may be able to make something work. They have a huge variety of boots. We looked at doing this with the IGN-1A coils and there was not enough room between the plugs and the frame rail.

[sen2two]

Originally Posted by C. Ludwig

Magnecore may be able to make something work. They have a huge variety of boots. We looked at doing this with the IGN-1A coils and there was not enough room between the plugs and the frame rail.

I have also looked at doing this for my Rx8. I was planning to use the IGN-1A coils as well. I am thinking now that making a 90 degree boot to attach the coils might work if you get creative with mounting angles. I am unsure if there is sufficient room though.

[t_g_farrell]

I remember a post way back when where someone fabbed up exactly what you are wanting
to do except for the HEIs. It worked ok, just added weight and made it hard to route some
stuff on that side of the engine.

I will say that anytime you can reduce a wire length it will help with the spark. Basic
physics there. Thats why OEM are engineered with smaller coils, they don't need a whopping
huge coil to drive the spark when they are direct connected like that.

I'll see if I can find the post on it.

This is the picture I was thinking of:

Do a google search rotary coil on plug to see other examples. The Ausies seem to be doing this a lot. Maybe Rice will chime in on it.