Thread: D2 Plug recommendations for LPG?

Bosch WR7KI33S platinum long life LPG plugs, gapped as out of the box at 0.7mm. You will have to order them, Bosch in Melbourne usually have them in stock and I have to order them through Burson Auto Parts. They work very well and don't wear out quickly like standard plugs. Make sure they are tightened correctly to ensure the gasket washer is flattened, or they will run hot.

Originally Posted by bee utey

Bosch WR7KI33S platinum long life LPG plugs, gapped as out of the box at 0.7mm. You will have to order them, Bosch in Melbourne usually have them in stock and I have to order them through Burson Auto Parts. They work very well and don't wear out quickly like standard plugs. Make sure they are tightened correctly to ensure the gasket washer is flattened, or they will run hot.

Thanks mate, I was totally bamboozled by stuff i read on net, one says this and one says that. just looking thorough part listings find them out of date, online confusing
NGK recommend one plug The dearest of course, PFR5G-11 1.1 petrol engine
but if you do a comparison to iridium they give BKR5EIX-11 which is a cheaper one.( but they don't list that as a suitable plug)
Then looking at Bosch online for LPG they list
Spark plug, Platinum Ir CNG/LPG gas
Bosch Order No.
0 242 240 652
Short No.
WR6KI33S
@$4.98 per plug is cheaper than the double platinum Champion plugs that I had in it. and even though I could buy them at a reasonable price, The Bosch plugs price is definatily better $ by far. I don't think some of these $18 -$20 plugs are good if you had a fouling problem for a short period and they carbon up, they never run the same.
so Hence I ask, and as you do LPG for a living your advise is appreciated

Bosch catalogues are often wrong, for example the LPG catalogue that they have online lists different heat ranges for the 4.0 in the D2 and the P38 even though they are exactly the same engine. NGK heat range "5" translates in most cross reference charts as Bosch heat range "8" and most LPG guides recommend one heat range colder, i.e. "6" in NGK and "7" in Bosch, the numbers going in different directions.

As I live at the top of a looong ascent from Adelaide via the SE Freeway, my plug recommendations tend to get a workout every day. WR7KI33S seems to be an excellent all round performer in all the low/medium comp V8's and I would only recommend the WR6KI33S in extreme performance conditions.

Originally Posted by bee utey

Bosch catalogues are often wrong, for example the LPG catalogue that they have online lists different heat ranges for the 4.0 in the D2 and the P38 even though they are exactly the same engine. NGK heat range "5" translates in most cross reference charts as Bosch heat range "8" and most LPG guides recommend one heat range colder, i.e. "6" in NGK and "7" in Bosch, the numbers going in different directions.

As I live at the top of a looong ascent from Adelaide via the SE Freeway, my plug recommendations tend to get a workout every day. WR7KI33S seems to be an excellent all round performer in all the low/medium comp V8's and I would only recommend the WR6KI33S in extreme performance conditions.

I said your the man who knows, I'll go you Recommendations, Thank
Again,
Cheers, Mario

Well I bought some of these plugs and set about putting them in today. How hard can it be? Thinks me.

All goes well until it comes time to start her up and go for a drive in my beautifully running V8 D2.

At low revs it ran very rough but got better at higher revs.

On the highway she purred along beautifully until it started back firing and ruining rough again. Next thing sweet as a nut.

Got home and made sure all the leads were attached correctly. Found a couple not quite right, so happy days methinks.

It was running better but still rough at low revs.

I then began swapping out the new plugs for old thinking I may have a dodgy one.

At about number 5 things started running and sounding great so I started putting the new ones back in 1 x 1 and testing as I went.

I got all but 2 new ones back in.

It still isn't running as well as I'd like but I'm now very good at swapping hot plugs.

Does this thing happen normally?

Could I have 2 faulty plugs?

Runs worse on LPG but still not great on petrol.

Does the car have to learn is got new plugs?

I've fitted over 40 boxfulls of these things, haven't had to send any back yet. However, I've occasionally seen people break the insulators with poor fitting plug sockets which is why I only ever do up plugs with a wobble drive extension. Also if one or more plug connectors wasn't pushed on properly, the coil affected could be burnt out. It's a known problem I believe, advice has it to never run a Thor without all plugs fully connected.

As an example, I managed to kill the coil on an EL Falcon the other day, testing for a misfire. I withdrew the plug leads off the plugs one-by-one on a running engine, then it died 100%. New coil fixed it. You have 4 individual coils in the packs to burn out instead of just one.

Not saying this is exactly your case but how does it run with all the old plugs back in?

Also you can test the lead continuity by measuring resistance across the two ends of each coil, i.e cyls 1,8,4 & 3 connect to cyls 6,5,7 & 2 in that order.

As for the ECU it doesn't need to learn about new plugs, so long as they work the ECU should be happy.

I'll put all the old ones back in today & see how it goes.

Thanks

I shot home at lunch time & put all of the old plugs back in & a test drive shows everything back to normal.

Smooth all the way through the rev range.

I'm assuming that means my coils are still ok.

I guess i'll start putting the new ones in 1 x 1 again until it starts running rough so i can send the crook ones back.

Will having a mix of plugs have any bad reprcussions?