Hi people,

65Bellett SMS'ed me and asked, "What's the NGK spark plug part # for a Bellett?" to which my first thought was "Buggered if I know..."

But a little Net research has revealed:

Recommended Plug: BP6ES
OR
Iridium IX plug: BPR6EIX

I got these numbers from (of all places; no offence Kiwis) the NGK NZ website! Nothing on the Aussie site (although it listed the Piazza, which it also listed under Holden and the Bighorn which just totally doesn't exist here uselessly enough - BIG HELP!) and nothing of use on the Japanese site, so HOORAY for New Zealanders!

This gets funny.

NGK USA shows no choices for Isuzu before 1981.

NGK Canada shows 1961-1966, then skips to 1981 to present. But, for 1961 through 1966, the only model listed is "Bellel" with a 2.0 liter engine, and no available plugs, wires, or O2 sensors at the end of the search. I don't think they sold the Bellel in Canada, but the engine size listed seems to indicate that this is actually Bellel and not a misspelling of Bellett.

NGK Finland has an English language website. They do not divide by years in the search, and list by model only. For "Bellete", they show 4 cylinder, unspecified displacement, power output, year, or motor code, spark plug: BP6ES, for liquified petrolium gas or compressed natural gas use BPR7EIX. Under the details they state the gap to be "0,7" (I think the comma is supposed to be the decimal place, but can't guess what the unit of measure is). There is an order number indicated as 7811, then some notes for the LPG/CNG alternative (for vehicles converted to an alternative fuel???).
They list the same for 117 Coupe. This may indicate that the same plug is used for SOHC and DOHC.
The resistor version of this same plug is listed for Piazza Turbo, but not for Piazza Non-turbo.

The mainland Europe NGK websites seem to be made from the same template and all show the same eight or ten Isuzu models. NGK UK is a totally different and they show only Piazza and Bighorn.

I managed to find some information on the NGK Japan website.

For Bellett, they show three rows:
1500cc, PR20, G150 engine, Showa 45-46
1600cc, PR50/PR90, G161 engine, Showa 43-48
1800cc, PR60/PR95, G180 engine, Showa 46-49

But, in each column to the right, the information is the same for all three rows:
Iridium IX plug / VX Platinum plug: BPR6EIX (BPR6EIX)
Stock Number: 3484 (3484)
Iridium Max Plug: BPR6EIX-P (BPR6EIX-P)
Stock Number: 2664 (2664)
Original Plug: BP6ES (BPR6ES)
Stock Number: 7811 (7822)
Manufacturer's Part Number: 9-82513103-0 (8-94219943-0)
Number Required: 4 (4)

This doesn't indicate any difference for SOHC and DOHC

For 117 Coupe, they show this same information for all of the 1600cc engines (G161), for the early 1800cc SOHC (G180/Z), and all 1800cc DOHC (G180W/WE), and all 2000cc DOHC (G200 DOHC).
However, they show the BP5ES/BPR5ES plug for the later 1800cc SOHC (G180/Z) and all of the 2000cc SOHC (G200).

Gemini listings are weird.
For PF50:
G161 and G161Z, Showa 49.11-51.10, BP6ES (BPR6ES).
G161/Z, Showa 51.11-56.9, BP5ES (BPR5ES).
G161, Showa 56.10-60.5, BP5ES-11 (BPR5ES-11)

For PF60:
G180, Showa 52.6-56.9, BP5ES (BPR5ES).
G180, Showa 56.10-60.5, BP5ES-11 (BPR5ES-11).
G180 DOHC, Showa 54.10-56.9, BP6ES (BPR6ES).
G180 DOHC, Showa 56.10-60.5, BP6ES-11 (BPR6ES-11).


For Piazza for G200 SOHC they show BP5ES-11 (BPR5ES-11).
For G200 DOHC they show BP6ES-11 (BPR6ES-11).

The choice between the 5 and 6 may indicate heat range and the compression ratio may dictate some of the changes in plug number for the same engine model number used in different models of vehicle.

Pretty much all engine variants use BP6ES (Belletts to Jackaroos) with 0.8mm gap or 1.1mm for electronic ignitions.
Iridium is probably not warranted - it'd be better to get a (Multi-spark) CDI.
But NGK pretty much comes up trumps for splugs.
(And stay away from multi-electrodes and other wank splug claims!)

That is correct, I have a box of them in my garage.!

I learnt today the R is for resistor - a 5 ohm resistor in the plugs for radio interfearance suppression. If you have an EFI conversion you should have the R variety.

from sparkplugs.com:


They also say the resistor variety never hurts, so its probably good to install in all cars, even carby, if they cost the same.