Spark Plug Confusion

[BRUN]

im considerin tryin some NGK plugs.....as ive tried Bosch 4s and Champion EON now

in Halfords it only lists BCP5ES......which is the basic plug......so i thought about the v-groove with the same values.....i.e. BCP5EV....but the thing is ive looked online and the gap size of the v version is only 0.6mm.....whereas the standard plug is 0.7mm....and im fairly sure the EONs ive used where 0.85mm or 0.9mm......so quite a difference

can anyone advise me ?

that same site is listing BCP5E as the v-groove version of BCP5ES....hmmmm

and its also listing 2 gap sizes.....you dont have to gap NGK plugs do you ?

even more confusion, my haynes gives the champion codes RC9YCC or C9YCX

which converts to BCPR6E or BCP6E

the R being for resistor.......does anyone know what affect it would have running plugs with / without a resistor.....ive heard somethin about interference with electrical components.........but do my magnecor leads suppress that ?

the gap size listed in the haynes is 0.80 +/- 0.05mm


im completely confused.....ive got 2 sets of plug codes, an then 2 more for ones with resistors in em.....an then more for different types

someone help !

 

[Nick Read]

All those codes ring a bell. I delved into the black art of plug codes a while back when I was looking for a colder plug for comp use.

Anyway the standard Renault plug is a Champion C7BMC, which was superceded by the RC7BMC. This is a twin earth plug.

The NGK direct replacement for this is *I think* the BCP6ES or BCP7ES. Or maybe the BKR7EK or BKR6EK...this is all just off the top of my head.

The Group N plug for the Willams and 1.8 lump was definitely the C6YCC and the C63YC. The 63 plug is a bit too hardcore for normal road use really. C6YCC is better. An R prefix version may be easier to get, and it wont affect the performance.

Dont ask me about NGK plugs, their codes are some kind of alien language, I cant make out what they mean and they code the same features with 3 different letters half the time. Also their heat ranges go back to front - the higher the number the colder the plug.

 

[BRUN]

cheers Nick.....one thing though....an R in the plug code......includin champion....means resistor

now, if Renault superceded the non-resistor plugs then there must have been a reason for it, however my halfords still lists the non resistor plug for my car

if the willy group n plug is the C6YCC, which is a non resistor plug, then the one for my car would be the C9YCX i assume, but if i need the resistor version then that is RC9YCC

the NGK equivalents of these plugs are

RC9YCC -> BCPR6ES

and

C9YCX -> BCP6ES

so should i be using a resistor plug then ?.......or not

p.s. if you need any NGK code breakin down then ask me an ill explain it

 

[BRUN]

the end letter is the electrode type

like on the ones above......its S....which is standard electrode

however.....if you look up the code without the electrode letter, you always seem to get V-groove plugs

like BCPR6E comes up as......
http://www.ngksparkplugs.com/images/tip/NGK_24B.jpg

now the v groove is listed as both Y and V on different websites for the last letter of the code

strangely though they dont seem to the 6 heat range plug with a Y code, yet do the 5........they do the 6....however its got a 1mm plug gap

Nick, my standard gap is 0.80mm +/- 0.05mm

so in theory a plug with 0.85mm would be standard......now im sure the EONs ive used said they have a 0.25mm bigger gap than standard, makin them 1mm or over

do you think such a gap would be ok on little 1.4

 

[BenR]

exactly...its a little 1.4!!!
the plugs will NOT make any difference to service life (the rate you change them) or perforance.

almost all modern cars with an ECU need a resistor type plug. It just stops the frequencies generated by the electricity flowing through the leads and plugs. leads are always sheilded and plugs should be of the resistor variety. unless your runing cabs and clockwork ignition.

the gap wont make a diff, it just makes the spark jump a further distance. good on highly tuned engines, but on a unmodded 1.4 energy....no point.

and dont use multi 4s please!!
there a waste of money.

 

[BRUN]

i knew you would b ere Ben, glad Nick replied first hehe

also i been chattin over email with a guy in technical at NGK UK

why dont you like Super 4s Ben

an i aint bothered about service life, ill happily replace em every 6k

an yea im gonna get the resistor plug, ive been told it doesnt affect performance at all

my car is modified but not much, it is chipped

 

[Nick Read]

hehe well the gaps not so important. The only reason for running a different plug is if you need to go colder or hotter - eg running at 6500 revs on the track firing nitrous occasionally in 30 degree ambient heat might well need a colder plug to fire reliably.

BTW Bosch Super 4 is a very good plug, I was always happy with them, likewise Champion EON 1.

 

[BRUN]

Nick what plugs are you using at the mo ?

 

[BenR]

sorry, i know were all allowed our own veiw....but he super 4 sucks big donkeys balls!!!

Fistly, its temp range is awful!
its just gimmic and since you dont care about service life, i wouldnt bother with a plug designed for loner service purely, not any better fireing.

NGK worked so much better with my N20 system. The supers ran so hot they turned blue!
once slight knocking was cured they were so good, reliable and generally the best i have used.

precious metal plugs are good in that they offer a longer service life with the single electrode! they can be more efficient with thinner electrodes and the gaps larger. This can improve cold starting with cold.fouled plugs and rich mixtures. They can also reduce misfires......BUT they do not produce more power!!!

one one last thing!
YOU CANNOT IMPROVE CYLINDER BURNING BY CHANGINE PLUG DESIGN! it is the shape of the chamber that dictates this one alight!

 

[Paul16V]

just get a standard set of NGKs. You cant go wrong. Ive heard of a lot of people having "fancy" expensive performance style plugs and having problems. I always get a good set of normal plugs and never had any problems.

 

[BRUN]

well the guy at NGK is sendin me fairly extensive emails, so im sure ill have the right plug for my needs

 

[coolspot007007]

when i switched to EONs i did notice a difference, but i dont know if this was shagged old plugs or something else, one did look a bit black.

 

[BRUN]

yea i noticed a diff with the EONs but that was when i got the car an it did need new plugs when i got it

i am tempted by em again as there good plugs but ill try the NGK this time round as there only £11

 

[BUTRE]

Brun

Where did you chiped your ecu? did you need to change prom?
I belive that the NGK spark plug for your car is the same for mine... what code are you going to use?

Im changind my wire set to lucas silicone. New ones, and they are blue. eheh whatever!

 

[Nick Read]

Well I gotta differ with you there Ben cos as you know I run a lot of gas and my Super 4s never misfired or looked like they were the wrong heat range. I know on paper they should be too hot a plug. But in real driving, even on track for half an hour with regular nitrous firing they still looked in perfect condition.

 

[BenR]

my engine is a bit more primative than yours though!
mines about 40yrs only in principal design and running gas in it means its not all perfect......and the manifold design means uneven distribution, 1&4 running leaner than 2&3 so i the supers started to play up....and i just dont wannabe sucked into their blatantly obvious marketing ploy!

 

[BRUN]

so are you runnin super 4s at the moment Nick ?.....the standard 16v ones ....or not ?

 

[BRUN]

BUTRE, i had my car chipped at Hill Power

and im going to get the V-Groove NGK with the 5 heat range

the code is BCPR5E