Spark Plugs.... ?

Victor Meldrew · Post by **Victor Meldrew** » Sat Jan 05, 2008 1:58 am

Best plugs to use in a K series when running with vmax/optimax/whatever the expensive stuff is?

I dont know for sure if it needs new plugs, but have read a few old articles in CCC... that talk about different temp rating plugs for different specs of engines.... giving a few bhp improvement if you get the right ones...

So I am happy to be shot down if I am talking nonsense but is there an optimum type of plug to use on a track day car that get ragged witless at every opertunity?

Rich H · Post by **Rich H** » Sat Jan 05, 2008 9:10 am

I would imagine that cooler plugs would be a good idea. Low comp engines need hot plugs to keep heat in, high comp engines need cool plugs to aid cooling (I read somewhere)

There is only one answer really, try them! Make sure the rest of the spark system is good too, new arm,leads and coils too.

robin · Post by **robin** » Sat Jan 05, 2008 10:23 am

There is no point using anything other than the plug specified in your owner's manual or equivalent from other manufacturers, unless you have substantially modified the airflow AND you're running a mappable ECU.

Cheers,
Robin

2F45T4U · Post by **2F45T4U** » Sat Jan 05, 2008 10:26 am

pull them and see what colour they are. if you know your mixture is spot on and they are black/sooty then theyre too cold. if theyre white. theyre too hot.

Victor Meldrew · Post by **Victor Meldrew** » Sat Jan 05, 2008 10:48 am

robin wrote:There is no point using anything other than the plug specified in your owner's manual or equivalent from other manufacturers, unless you have substantially modified the airflow AND you're running a mappable ECU.

Cheers,
Robin

Might just get myself a new set of std plugs then, they were discoloured when I had the problem with the inlet manifold leak. No4 was black,sooty and sticky.. the rest were all white. The engine runs Ok but you can never leave any stone un-turned in the search for cheap horsepower.

tut · Post by **tut** » Sat Jan 05, 2008 11:32 am

Don't listen to the flat hat brigade John.

Those gold/platinum/iridium tipped ones with rare earth cores and uranium injected carbon fibre jackets at £50 each must be better, otherwise how could they justify the price?

tut

robin · Post by **robin** » Sat Jan 05, 2008 5:00 pm

Shut up tut

Robin

ceejam · Post by **ceejam** » Sat Jan 05, 2008 6:46 pm

Just because they're made of expensive metals, that doesn't make them better.

A gold frying pan would be expensive but would melt if you tried to use it

I tend to alwas use Champion (British) Spark Pkugs in British Engines.

K series uses RC series, RC9YCC is standard for most Rovers, 7s a bit cooler for high performance engines. What is the "handbook" recommendation for the Liz?

tut · Post by **tut** » Sat Jan 05, 2008 7:32 pm

"Just veauce they;re made of expensive letals"

One hell of a sentence there Jamie, but of course you realised that I was extracting the urine.

tut

ceejam · Post by **ceejam** » Sat Jan 05, 2008 8:47 pm

My typing truly is terrible sometimes!!

I did detect a hint of sarcasm there Tut