Hi All,

Ive read a couple posts about plugs and it seems that for LPG it must be 0.8 gap or dosent work to well when its 1.1 as thats the standard gap for petrol when its run.

I have also read that its better to get a spark plug that is longer so it stick's in the combustion camber so its closser in and apparently burns the fuel alot better. Some people have also reported they have noticed when doing this and engine running smother and getting more kms out of a tank and according to JMM he gained a extra 4 or so kw's.

I have a EF which is duel fuel and run a impco lpg setup and went past my local spare parts shop and spoke to the guy there that know's abit about ford's and LPG. I asked him this question and he showed me 3 different plugs and one plug was 3-4mm longer. Apprently its duel fuel plug and is made by NGK ZGR6B-11 and seems to have 1.1 gaping but dont have the gauge to check it.

So NGK ZGR6B-11 is longer but has a gap of 1.1 and its a duel fuel plug and from threads and mechanics the gap is sopposed to be 0.8 for LPG.

I wonder why this plug is 1.1???

Should i re gap them to 0.8 before i use them???

Im thinking of trying them as they are and then get another set and gap them to 0.8 and see what differences i find.

I have always use Motorcraft/Denso plugs W16EXR-U which have been good but want to try and see how true this subject is and if it does make a difference

All feedback is welcome and i will post some pictures of both the plugs i have

Also do all 4.0L engines from EA-AU have the same thread??? i mean can u use a plug from AU in a EF engine and vise versa from EA-AU engines???

i think there has been a million threads on plugs but you did seem to put a bit of effort into ur post

i have been using NGK ZGR6B-11's gapped at 0.8mm and they are prefect for duel fuel

they are factory gapped @ 1.1mm cause i believe they were/are designed for use in the xr6 motors

all threads ea-au are the same

I've been using NGK ZGR6B-11 @ 1.1mm in LPG powered cars for 10 years without issue.

Here is another option a bit from left field.

I am using KLG three prong plugs gapped at 1.0mm. They are $5 a pair from Super Cheap, and are great on Petrol and LPG.

BenJ

Apparently Bocsh WR8LC is sopposed to good as well

Im going to try a few different plug and report back and see if there is any benefit between them all and see if the engine runs better and if it gets better kms as well.

the zgr6b-11's are for falcon motors with the tickford head (xr6, ghia etc..) they are one heat range colder then standard so better for lpg, just need to be re-gapped

cool i didnt know that, ill fit them in the next couple weeks and start testing and see what i find then at least then we can find a combination that works.

I would like you to test the KLG plugs that I am using. I think you will be surprised.

BenJ

Where do you buy them from, ill grab a set and give them a go

Been using autolite 985 for the last 6 months or so, gapped at 0.9mm.

never had an issue.

Looks like i have 4 sets of plug to try hahaha

Supercheap auto.

They have 3 prongs. And for $15 for all six, is cheap performance.

BenJ

never seen a multi electrode plug make more power. last longer yes, more power no.

i'm going to buy these ngks we were talking about

but i do not for the life of me know what gapping a spark plug is

how do i gap it from 1.1 to .8 mil?

i've got a duel fuel imco EF with an xr6 motor

thanks