jimhc

iTrader: (1)

how much power are the 071 spark plugs safe to use

KSA-Cossie

iTrader: (4)

up to 600 bhp mate

tabetha

As said, certainly a very hardy plug, not the best for running/smoothness but still excellent.
tabetha

jimhc

iTrader: (1)

as there only a tenner thot be better using them instead of the ngk at 40quid a set. what do you mean by not best for runnin smoothness

mechanic28

iTrader: (5)

use mine in my 500hp cossie,tabetha means as in they dont make the engine run as smooth as some like it can be abit uneven at idle etc

tabetha

You will get a better idle and slow speed running ime with the precious metal ones like iridium, but 4 times the price, I think it's worth it, still very good with the 071, just that little bit better imo/ime with IK range.
Fuelling needs to be spot on though as the IK range are hyper sensitive to fouling I've found and don't recover often if heavily sooted, and defo not if ever made wet.
tabetha

jimhc

iTrader: (1)

the ngk foul up if left to idle to long. what do you mena by imo ime ik range

tabetha

imo = in my opinion, ime = in my experience.
If a plug is fouling when idling too long, either it is too cold a heat range, or the engine is far too rich, or a combo of both, I found the Nippon Denso IK31 plugs way too cold, so use IK27, as these are a hotter plug, but perfect for my needs.
tabetha

jimhc

iTrader: (1)

pfr7b ngk plugs?