Found a cool buell video...dual plugs and coils too

[konarider94]

Anyone see this yet?

Its a cool video but I wish it showed how he added the dual spark plugs. You can see in his pictures he clearly has 2 coils and 4 spark plug wires. Ive been thinking about running dual coils and increasing the plug gap to get better ignition, but I have no intention of adding another sparkplug.

 

[Theycallmecrash]

I believe its easy enough for a machine shop to add the additional hole on the other side. Its odd practice for older harleys. Cool idea i can see the benefits as small as they are

 

[konarider94]

edit: found a pic of an xl1200 head. wonder if it fits next to the temp sensor or if he had to move it. i havent seen this before on a buell or sportster.

 

[nemoxb]

sportster sport had dual plug heads stock.

 

[Loki]

The point of this is just better spark? Run lower octane?

 

[Theycallmecrash]

Better fuel burn, combustion efficiency, also where one plug might miss fire the other probably wont. About really all it does, more bang for your electrons.

 

[konarider94]

Two flame fronts for a faster and more complete burn

 

[snrusnak]

Two flame fronts for a faster and more complete burn

[up]

This is becoming fairly common on modern engines(for performance reasons but also mainly for emissions reasons I believe. My truck (dodge ram 4.7L) has dual plugs. The dodge 5.7L(hemi) also has dual plugs. The 4.7L didn't have dual plugs until 2008 when they made some revisions. The revisions(dual plugs, revised cylinder head design, intake manifold design, etc) bumped power and torque from 235/295 to 310/330. Quite a difference without a change in displacement or overall engine architecture.

My truck is way over due to have the intake bank of spark plugs changed(~30k miles over due) and it runs 0-60mph about 0.5 seconds slower now than it did when the plugs were in their "useable" range. I'm not 100% sure it's all due to the plugs, but I believe at least some of the loss in performance is due to the plugs. Like I said above though, I believe the main reason is for emissions, not performance.

 

[vtech007]

The dual plug/dual ignition system set up is used in some very high performance engines (example: top fuel). Redundancy for when one plug does not fire having the other spark available. Good idea for any engine, I would say. Can't think of any major drawbacks.

 

[snrusnak]

Can't think of any major drawbacks.

My only thought here is cost. I have 8 iridium plugs and 8 copper plugs in my truck. Factor in 8 coils that the boots often rip when pulling them off the plugs, that gets pricey come tune up time lol.

In all seriousness though, I agree it's a good design. Really has me thinking about the bike now

 

[Theycallmecrash]

My only thought here is cost. I have 8 iridium plugs and 8 copper plugs in my truck. Factor in 8 coils that the boots often rip when pulling them off the plugs, that gets pricey come tune up time lol.

I love these trucks, cause when they come into work, its pay day. The charger guys with coil on plug like to switch all their plugs over to iridiums, through a shop isn't cheap add labor in, $500 tune up.... Mmm gravey.

 

[konarider94]

i had a hemi grand cherokee and it did not run well on iridiums for whatever reason. it did not make sense to me but there were other reports of it happening on jeepforum too. some people had no issue though. i went with copper and just changed them more frequently. never heard of people mixing them

 

[Theycallmecrash]

Its mixed because the ignition systems on some of those dodges, are "waste spark" setup.

 

[Red93stang]

Good vid[up]

 

[P3_techman]

That is a badass video. Super well done on their part with the content and editing, loved that virtual disassembly intro.