The Definitive correct NGK Spark Plug thread

[ThreeM30s]

There was an hilarious thread from last year about spark plugs, but I didn't want to drag it up as it had thankfully died naturally. To be fair it is one among many... and oh now, here I am starting one more. But I hope, this Spark Plug thread will end them all!

I've been trying to work out the right plugs to get and those sort of threads got me nowhere, (other than entertained). They really demonstrate the problems with not being specific about the item being discussed, the model, the year; let alone butt dynoism and things like 'I changed those out for these and the new ones are excellent' debates that continuously compare old and worn to new quoting poorly measured results.

Now I know we all try, but really half the time we are doing stuff at the same time as doing other things, so the results are all over the place. Anyway, to clean this up I did some research. This thread attempts to ascertain which NGK plugs fit early M42/M50/M60 motors and provide pics and details with fitment specs for each type.

Looking at what NGK make available, and the fact that all these plugs will physically fit an M42, M44, M50, M52, M54, M60, M62 engine, inc. the TUs. It is easy to see why aftermarket this can all go wrong. A lot of it is because we tend to refer to them by the design types, not by part numbers. And the local part suppliers that are more familiar wth Ford and GM easily mix them up, as can their wholesale suppliers. Then after that, we go fitting them and go blurting about getting 'mixed results'

So here they all are, from Latest 'and greatest' to the oldest and 'most proven' w/ pics, applications and indicative pricing:

1: 2: 3: 4: 5:

To suit modern engines in e31, e32, e34, e36, e38, e39 and later:

1a. For M52TU/M54/M62/N62/M73 IX iridium 6418 BKR6EIX .032" $7.83
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) HexSeat, Resistor, Solid Terminal, ISO Length, Projected Tip, Fine Wire (0.6mm) Iridium Center Electrode, Tapered Cut Ground Electrode, .032" (0.8mm) Gap, Heat Range 6

2a. For M52TU/M54/M62/N62/M73 GP platinum 7092 BKR6EGP .032" $3.15 Comes with .040" (1.016mm) gap?
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, JIS Height, Projected Tip, Platinum Tipped Center Electrode, Trapezoid (Beveled Cut) Ground Electrode, Heat Range 6

3a. For M52TU/M54/M62/N62/M73 Multi-ground (Quad electode) 3199 BKR6EQUP .032" $8.48
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, ISO Length, Projected Tip, 4 Ground Electrodes, Platinum Tipped Fine Wire Center Electrode, Heat Range 6

4a. For M42/M44/M50/M60 Multi-ground (Dual electrode) 2288 BKR6EK .032" $5.19 Comes with .035" (0.9mm) gap?
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, ISO Length, Extended Projected Tip, Dual Ground Electrodes, .032" (0.8mm) Gap, Heat Range 6

4b For M52TU/M54/M62/N62/M73 Multi-ground (Dual electrode) 7969 BKR6EKUB .032" $5.82
Multi-Ground Plug, 14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, ISO Length, Projected Tip, Dual Ground Electrodes, Heat Range 6

5a. For M52TU/M54/M62/N62/M73 V-power 6962 BKR6E .032" $2.89
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, ISO Length, Projected Tip, V-Power (V-Grooved Center Electrode), .032" (0.8mm) Gap, Heat Range 6

Note: Any one of the above plugs will physically fit an older M50 or M60, but the newer models (Type #1,2 & 3) are NOT reccommended by NGK- let alone BMW in their lists. (i.e. they are only listed for use on the later engines such as M52TU, M54, M62, N62). This does not mean they will not work or provide good results, as we would often like to think they might.

To suit earlier M10, M20, M30 and M70 engines in e21, e23, e24, e26, e28, e30, e32, e34:

1b. For M10 IX iridium 6597 BPR5EIX .036" $7.83
14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Removable Terminal, JIS Height, Projected Tip, Fine Wire (0.6mm) Iridium Center Electrode, Tapered Cut Ground Electrode, .032" (0.8mm) Gap, Heat Range 5

1c. For M70 IX iridium 2477 ZFR5FIX-11 .032" $7.83
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Extended Projected Tip, Solid Terminal, ISO Length, Fine Wire (0.6mm) Iridium Center Electrode, Tapered Cut Ground Electrode, .044" (1.1mm) Gap, Heat Range 5

2b. For M10 GP platinum 7082 BKR5EGP .036" $3.15
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, JIS Height, Projected Tip, Platinum Tipped Center Electrode, Trapezoid (Beveled Cut) Ground Electrode, Heat Range 5

2c. For M20/M30 GP Platinum 7102 ZGR5AGP .028" $3.15
14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Removable Terminal, Extended Projected Tip, Platinum Tipped Center Electrode, Trapezoid (Beveled Cut) Ground Electrode, .040" (1.016mm) Gap, Heat Range 5

2d. For M70 Single Platinum 7098 ZFR5FGP .032" $3.15
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, ISO Length, Extended Projected Tip, Platinum Tipped Center Electrode, Trapezoid (Beveled Cut) Ground Electrode, .040" (1.016mm) Gap, Heat Range 5

2d. For M70 Double Platinum 3741 PZFR5F .032" $12.06 (Extra Long Life Double Platinum)
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Extended Projected Tip, Solid Terminal, ISO Length, Fine Point Platinum Center Electrode and Platinum Tip Laser Welded on Ground Electrode, .032" (0.8mm) Gap, Heat Range 5

5b For M70 V-power 7558 ZFR5F .032" $2.89
14mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Extended Projected Tip, Solid Terminal, ISO Length, V-Power (V-Grooved Centere Electrode), .032" (0.8mm) Gap, Heat Range 5

5c. For M10 Traditional 7734 BPR5ES .035"
14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Removable Terminal, JIS Height, Projected Tip, .035" (0.9mm) Gap, Heat Range 5

5d. For M10 V-power 1233 BPR5EY .035" $2.89 Comes with .032" (0.8mm) Gap?
14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, Projected Tip, JIS Height, V-Power (V-Grooved Center Electrode), Heat Range 5

5e. For M20/M30 V-Power 5077 ZGR5A .028" $2.89
14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Extended Projected Tip, Removable Terminal, ISO Length, V-Power (V-Grooved Centere Electrode), .035" (0.9mm) Gap, Heat Range 5

5f. For late S38 (e34) 3481 DCPR6E .024" $2.89
12mm Thread, 19mm (3/4") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Solid Terminal, Projected Tip, .035" (0.9mm) Gap, Heat Range 6

5g. For early S38 (e24, e28) 7912 D7EA .024" $2.89
12mm Thread, 19mm (3/4") Reach, 11/16" (18mm) Hex Size, Gasket Seat, Non-Resistor, Stud Terminal, .027" (0.7mm) Gap, Heat Range 7. NOTE: Does not include terminal nut, if necessary, order part #067606-0051

That said, here is the pfaff from NGK (their explanation of the differnces for all us plebs):

NGK iridium plugs represent the ultimate evolution of spark plug technology and performance. The iridium center electrode is both stronger and harder than platinum. This allows NGK engineers to design an ultra-fine (0.6mm)center electrode reducing the voltage requirement for spark. This allows for a brighter, stronger spark from your existing ignition system. The ground electrode has a tapered cut at the firing end which reduces quenching for better flame core growth and increased ignitability. The combination of fine wire center electrode and tapered cut ground will increase performance, improve acceleration, and fuel efficiency.

NGK G-Power offers the performance and durability of platinum at a competitive price. The center electrode is fine wire platinum for better starts, superior acceleration and better fuel economy. Trapezoid cut ground electrode to reduce quenching.

Multi-ground electrodes improve ignition capabilities and are less sensitive to increased voltage requirements due to gap growth. Designed to specific manufacturer ignition requirements in either supplementary gap, intermittent discharge, or semi-surface discharge, all for various firing tip self cleaning abilities. Platinum center electrode for extended life. Multi-ground plugs maintain all features of NGK's traditional plugs including corrugated ribs, pure alumina silicate ceramic insulator for greater strength and better heat transfer, copper core and triple interior seal.

NGK's unique V-Power design directs the spark to the edge of the electrode where it develops more rapidly, this increases ignitability even in lean burn conditions. In addition the NGK V-Power plug has all the features of their traditional plugs including corrugated ribs, pure alumina silicate ceramic insulator for greater strength and better heat transfer, copper core and triple interior seal.

So there you have it. As it turned out, my local parts guy (who seemingly knows Bimmers really well) gave me a set of the very expensive quad-electode plugs, (BKR6EQUP) for my old M50, which of course are the most expensive (and are not reccommended for it by NGK). So I was scared to put them in, but after collecting the above, I have more courage. Will they work well? I am still half tempted to go back & swap them for a set of stockers (BKR6EKs). What do you all think?

[Kevin Da Clean1]

... So there you have it. As it turned out, my local parts guy (who seemingly knows Bimmers really well) gave me a set of the very expensive quad-electode plugs, (BKR6EQUP) for my old M50, which of course are the most expensive (and are not reccommended for it by NGK). So I was scared to put them in, but after collecting the above, I have more courage. Will they work well? I am still half tempted to go back & swap them for a set of stockers (BKR6EKs). What do you all think?

Those are the same I put in my 98 E36 M3 sedan & they are the same great plugs I have now in my 2002 M5. They are very good plugs & the car runs well with them in it... !

[ThreeM30s]

Those are the same I put in my 98 E36 M3 sedan & they are the same great plugs I have now in my 2002 M5. They are very good plugs & the car runs well with them in it... !

Good news, thanks. I'll give them a try.

BTW: Interestingly, the single electrode ones BKR6E are listed for M54 and M52TU, but are 'not listed' for the M50. What's with that? Did the M50 come with dual electrode plugs back since 1990 and the M54's not? Hmmm. I don't think so...

[ThreeM30s]

Updated the list to include M10, M20, M30, M42, M44, M62, n62, M70, M73, S38 engines as well.

[fragzem]

Good news, thanks. I'll give them a try.

BTW: Interestingly, the single electrode ones BKR6E are listed for M54 and M52TU, but are 'not listed' for the M50. What's with that? Did the M50 come with dual electrode plugs back since 1990 and the M54's not? Hmmm. I don't think so...

i know this is a 3 yr old thread.. but that's interesting because im ordering plugs now and RockAuto doesn't list them as compatible. Ordering them anyway.

[Sroor9001]

Thanks got my BKR6EGP PLATINIUM want to change from Bosch bmw PLATINIUM to ngk PLATINIUM Iam thinking Bosch PLATINIUM ruined so many coils in my car just in case it's normal same situation will be with this set of ngk
those Bosch spark plugs only 30k on them But will keep them and see what's the issue is it normal died coils or it's the spark plugs want to switch to irradium but it's too expensive

[ricks5series]

This article is interesting in spark plug design. Sorry to add to an already confusing topic, lol

https://www.sciencedirect.com/scienc...90447912000883

[waterx0x]

Long and great article, M20, n62, M73, M62, n62, M70 should be included