Extended reach spark plugs.
 

I searched for extended reach spark plugs but found no results. FM has these, and I see a ZF number, which if i remember correctly is a Honda plug. Anyways, I am running the BKR-7ES-11 Right now. I really dont think i need 7's. But as hot as it gets around here, I figured that it would be a good precaution. However, 7's transfer more heat to the coolant, right? So back on subject. Is anyone running the extended reach plugs? If so, What are your results.
Linkasaurus Rex

Edit: I found another cool link that explained in greater detail, so are these optimium for use in our cars?

Another cool link

Technically, yes. Trying to quantify the magnitude of its effect on the cooling system would be about the same as saying that carrying one extra packet of sugar in the aft galley increases the weight of a Boeing 747 and thus has a negative effect on its fuel economy.


I'd love to know what the purported benefit of having part of the threaded section protruding into the combustion chamber is.


FWIW, there's a great parametric search tool for NGK plugs here: http://ngk.com/search_char.asp?seenW...nufacturerID=1

Awesome link. I was wondering the same thing. Not not knowing about how electrode location effects the way the flame travels in the combustion chamber. Would this have any effect on detonation resistance? I think i will shoot them an Email and see their response. It seems like it would not be a great idea.

Honestly, I can't imagine any benefit to increasing the number of sharp, pointy things inside the combustion chamber.

I've never tried sticking a plug with a 26.5mm reach into a head to see how far out into the chamber it extends (at some point, I'd start worrying about the intake valves hitting it) but I don't recall that a standard 19mm plug winds up being terribly recessed.

It seems like it would encourage detonation to me. A big hot metal thing in the middle of your combustion chamber.

Ssh it's the secret to big N/A power on the cheap, compression increasing spark plugs. Yay for power plugs :jerkit:.

Lulz

Wow that's a great idea. Even better than jbwelding quarters on your pistons.

Seriously tho, it does increase compression. I wonder if there are special fatty tip plugs just for this.



FM actually just sold me some zero reach plugs for "high boost". Jeremy said he had been able to run over 20psi with these NGK plugs without spark blowout. Stock coizl.

They why do they have extended reach plugs listed for boost? Epic gheyness. I wish the JB weld guy went through with it.

Hi,

The extended plugs get the electrode farther into the combustion chamber
for a better burn. They also advance the timing slightly, as the flame
front starts slightly closer to the piston. I hope this helps, let me
know if there's anything else I can do for you.

Thats the reply. Sounds like not what i want. I will keep my BKR's.

Yes. Keep the BKR7E.

Uhm, ok. I guess I can't argue against the idea that moving the spark gap towards the center of the chamber would have the effect of decreasing the time elapsed between the spark event and the completion of the burn (which I'm fairly certain is not the same thing as advancing the timing), though I'm hard pressed to imagine that there would be a repeatably quantifiable gain from this.

Might be one of those things that gives you that extra .01%. Probably worthwhile for a qualifying lap in Formula 1.

I dunno... I ain't gonna knock it 'cuz I haven't tried it. There are some conflicting ideas rolling around in my brain right now as to whether, ignoring the idea of hotspots and preignition, projecting the electrode further into the chamber and initiating the burn from a point closer to the geometric center of the chamber would increase or decrease the propensity for detonation at a given BMEP (or allow a given engine to be tuned for a higher BMEP.)

Thats what I was thinking.... exactly. More surface area to absorb heat would just be like a giant bur on a piston or valve. The advancing thing makes sense to me somewhat, but i would have to draw you a picture why. I am not really sure that I want to guinea pig those. Not knowing really how the flame travels from the point of combustion to the rest of the mixture in the cylinder, and how it is flowing in there.... so on and so forth. Your an engineer, I am about a third of one.

I'm not really seeing how it will advance the timing. Even if the burn begins in a spot closer to the piston, it still takes roughly the same amount of time to develop into a useful combustion event. This time shouldn't change because the spark location moved a few mm. IMHO NGK is making a wild guess that it will and marketing it.

Or rather, NGK is hoping that the target market is unwitty enough to accept their marketing as fact.