Spark Plug Question : NGK B-9HV or B9HS Super Combat

[JackM]

The manual for the model 97 Super Combat calls for an NGK B - 9HV. I tried to look these plugs up on an NGK site, but couldn't find them. Is a B 9HS the same or similar? Meanwhile, here's a pic of my 97 project, having just installed a new kill switch and rubber intake boot from Terry Larson.

[matt glascock]

I hate to sound like a pitchman for ebay, but there are some things that you just can't find elsewhere - including our beloved parts houses. There are scads of B-9HV plugs available on ebay for about five bucks apiece.

[JackM]

Matt, do you happen to know what the difference is between the HS and HV? I already have an older B-8HS and a new B-9HS. Did NGK quit making the B - 9HV plugs? Thanks

[admin]

Same heat range. 9
Same length. H
Different electrode(shape and/or material). S = standard V = ?

[Bullfrog]

I can't remember exactly what the "V" designates, but my vague memories are of some sort of fine wire electrode. I wouldn't have any problem running the "S" (standard) electrode

But I'd certainly stick with the "9" heat range and the "H" reach.
Ed

[matt glascock]

Here's the dope:

B = thread size (14mm) and spanner size (20.8mm)
9 = heat range
H = reach (12.7mm)
S = copper core center electrode
V = gold-palladium center electrode (faster/better conduction for continuous high-rev racing application)

[JackM]

Thanks, Matt. I found a "V" type on ebay and will post a pic of it and the S type side by side when it arrives.

[matt glascock]

Cool. That would be interesting to see the side-by-side comparison.

[Dale]

Here's the dope:

B = thread size (14mm) and spanner size (20.8mm)
9 = heat range
H = reach (12.7mm)
S = copper core center electrode
V = gold-palladium center electrode (faster/better conduction for continuous high-rev racing application)

Thanks for locating the details Matt. I've been on the go and haven't been able to research it further.
Dale

[matt glascock]

Glad to fill in the details, Dale. I use the NGK B-9EV spark plugs (same plug only with 19mm reach) in my 1978.5 RM250-C2 so I have the back story on the gold-palladium firing tip. My recollection is that was the hot set-up of the day but I think they were probably made obsolete with the new iridium plugs we use nowadays.

[racerclam]

the Iridium is the best , fine wire even more so than the v plug and tougher material. The smaller the wire diameter concentrates the current making it easier to jump the gap under high cylinder pressure and High RPM , which makes them popular for supercharged engines and nitrous , as well as screaming 2 strokes but they arnt cheap . I use them in my bikes and truck

Rich

[matt glascock]

I'm with you, Rich. I use them in my Super Rat and Combat Wombats (all with PVL ignitions), as well as my hopped-up M94 Wombat. They are all screamers. I swear by the NGK ix plugs, but they are a tad spendy. Worth it, though.

[hodakamax]

Good info Gang. I'm behind the times and will give them a try!

Maxie

[matt glascock]

Hi Maxie, All the high-performance iridium NGK plugs have codes ending in "IX" as in in BR-9HIX. They come in blue packaging as opposed to the traditional yellow (or red for the racing models). I'm trying to figure out how to get my table of all the NGK codes in a format that I can import onto the forum. Its good information and helpful for cross referencing in the odd situation where NGK plugs are unobtainable.

[Steve Arnold]

I use NGK B9HS for my Super Combat. Can not find local, get from Hodaka-Parts. Buy 4 or more at a time.

[Joe Ormonde]

I`m a Champion fan. I have the 1975 Champion Master Catalog and trying to cross over Champion to NGK is TOTAL CHAOS! Here`s why. NGK B9HC: Champion L78. NGK B8HC: Champion L78 or L81. NGK B7HS: Champion L81. NGK B7HCS: Champion L85. NGK B7HC: Champion L86. NGK B7HS: Champion L81. NGK B6HS: Champion L86. So by the Heat Range,depending on how you read the Champion Cross Reference Chart,the Champion L86 Spark Plug covers 4 NGK Heat Ranges! Joe Ormonde.

[taber hodaka]

This is what is nice about the hodaka manual it cross references NGK plugs and racing spark plugs sequenced from hot to cold page 160. Listing NGK, Champion, A-C, Auto Light, Bosch, KLG, and Lodge. I have lost several engines to Champion plugs, the porcelain fell off and ruined the engines. The hodaka chart shows L85 for the B6H. NGK plugs get colder as the numbers get bigger, Champion plugs get colder as the numbers get smaller but strangely not always. You can generally know the heat range of the plug by looking at the electrode. -----------------Clarence

[JackM]

Side by side pic of two NGK spark plugs. The B9HS on the left has a bigger electrode than the B9HV. By the way, does anyone know the resistance values of the primary and secondary coil on the 97 Super Combat or 98 Super Rat?