Yes, i would have to say it would help with an increase in power-but how much, i do not know...

Having more projection of the plug will create a better igniter in the combustion chamber where as the shorter protrusion will definently need a strong spark to keep up with the plug with a longer protusion.

But if you want to put it into practise i would be very interested to see how it does make a difference in rwkw.Meaning if you can get onto a dyno and use your standard ef.el plug protrusion type plug and then switch to the earlier xf to ed plug and see what benefit will come from doing this.

The only thing i see happening is making sure that you have suffcient plug to piston clearance and also running a different heat range plug to compensate the extra heat being produced in the combustion chamber (only really for high performance applications/would be fine for everyday streeter).

well the photos at the start of the thread take care of knowing what the clearence is like. (kind of half the reasong the photos are there)

there will not be enough change, if any, to warrant a colder plug.


like has been said earlier, sustained high rpm use (hill climbs/ sprint racing/ circuit racing) will not suit the long projection plugs. Nor will the use nitrous oxide.

but strip use and daily driving will be fine.

I think I see a dot....?????????? whats it mean ?????? LOL

changed my mind

LOL

NGK Equivalent Part ZFR4F-11/ZF4A-11

Bosch Equivalent Part FR9HC+

The bosch plugs are used in 4l Jeeps, so they have them down at supercheap auto.

im a bit confused!

I thought the ZGR6B-11 plug had more projection than the standard BRP5EY??

anyone got a pic of them side by side?

or are we saying that Autolite/Denso the only way to go for the long projection plug?

It does, it is the same length as the standard NGK BRE527Y EA/ED plug.

BRP5EY is shorter projection EF/EL plugs.

Have another look at the pic i posted a few posts back!

Next service I will put in a set of NGK BRE527Y plugs and see if there is some truth behind using longer projected plugs into EF/EL heads.

are the ED plugs gapped the same as the EF ones out of the box?

i doubt you will feel any power increase.

you'd be better off doing some long term fuel economy testing, say a month of regular driving on the both types.
reason being is anything that can create more power with out added air and fuel must show some sort of economy gain.

that part number is for double platinum.

mocks sells all three types but advertises the regular plugs

^^^^^^^^^^^^^^^^^^^^^^
that is a fair price for a top of the line set of plugs plus includes delivery.
search how much for the best bosch,splitfire,msd etc

I think I will stick with my denso K20TR11 thanks anyway.

gap is to small

A projected insulator plug will give slightly higher compression as well as the flame front being better for combustion,this may be where the gains JMM gets.