Advice on spark plugs please!

[ultimatime30]

Anyone have a preference as the best ones to have?

[HJG-E30]

I've always found single electrode standard NGK to work best

[Mo13]

as above NGK

[ultimatime30]

Are they the copper core ones?

[Speedtouch]

NGK BPR6ES are recommended as being the best for the M20 engine.

[jmc330i]

Stay away from the multi electrode plugs. I can remember a thread on a Vaux forum about an XE lump that had one of the electrodes bouncing round inside the cylinder, but because there was another electrode making a spark and there was no misfire, the guy didn't realise anything was wrong until the damage was done.

Possibly not a common problem, but something I'd steer clear of anyway.

[B7]

NGK BPR6ES are recommended as being the best for the M20 engine.

This.

Has been proven on the rollers more than once that they run better with an NGK than other plugs.

[Quaser]

what about m50/m52 engines

maybe we should have a wiki on recommended spark plugs for all engine variations

[ultimatime30]

Can't believe how cheap them NGK plugs are!

[Morat]

But good quality. Hard to believe eh?

[ultimatime30]

Absolutely! Almost wish I had a V8 in it now hehe

[ultimatime30]

Thanks for your replies guys, appreciate it

[faze30]

NGK ARE THE ONES DUDE

[zaust]

Early high comp m20' s and m10's need Bosch and all later engines ngk.

[reggid]

NGK BPR6ES are recommended as being the best for the M20 engine.

This.

Has been proven on the rollers more than once that they run better with an NGK than other plugs.

if only the rollers were that repeatable...., a properly calibrated and monitored engine dyno could pick up something perhaps. id like to see something conclusive new plug stock vs new plug BPR6ES (one heat range cooler)
in reality there is not going to be any decernable difference between the stock and BPR6ES unless you have a much higher comp lump and if it is not a higher comp lump you could get too many deposits which could be a minor issue long term. ive run BPR6ES and bosch stock ones and ZR5xxx and even BPR5ES it is much of a muchness TBH. ive dyno tested fancy CDI coils systems and they do SFA on a naturally aspirated engine with minor redlimit increase