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Originally posted by Micko

How does it work then - i was told to gap them to 0.7 which quite small.

Does this mean i will get a hotter, more intense spark?

What is the normal school of thought when you increase boost?

Gap to .7 or .8 mm cos most of the modern plugs gap to 1.1mm hence the 11 on the end of the plug number.

The large gap is what gives a bigger stronger spark because it makes the coil build up a larger voltage to fire the spark across the gap.

The trouble is with turbo engines running larger than stock boost will blow the spark out while it jumps the gap ( simplistic terminology ) hence the need for a smaller gap , which then gives a weaker spark and is the reason why splitfire or cdi type ignitors are reqd on BIG boost engines.

Got it ?

Cheers

Ken

Originally posted by Micko

I think he was annoyed with how you addressed his indescretions...a little more tact would have been appropriate

Nah stuff it, just walk over and deck him. Hehehe

Tell us first so we can set up seats and get the beer and chips out.:P

Cheers

Ken

Originally posted by gtrken

Gap to .7 or .8 mm cos most of the modern plugs gap to 1.1mm hence the 11 on the end of the plug number.

The large gap is what gives a bigger stronger spark because it makes the coil build up a larger voltage to fire the spark across the gap.

The trouble is with turbo engines running larger than stock boost will blow the spark out while it jumps the gap ( simplistic terminology ) hence the need for a smaller gap , which then gives a weaker spark and is the reason why splitfire or cdi type ignitors are reqd on BIG boost engines.

Got it ?

Cheers

Ken

Cylinder heat causes injector fuel to ignite before the spark flashes over :P

Originally posted by Micko

Thanks Ken - I had heard about the spark being 'blown' out.

Good work macka - blamed the wrong bloke...you are a tool (7/16 combination ring spanner if I recall):bahaha:

Maybe u should read more carefully,

I asked if he was the guy who hoons around my street picking up some girl he said yes

Im not going to change my driving habits because thats the way i drive and thats not going to change...

I accused no one

Originally posted by Micko

This plug talk is doing my head in...

So if I reduce the gap I should use a hotter plug to keep the actual spark the same?

Why do people go colder in most higher boost applications?

Colder plug means it will take heat , boost and thrashing better without melting or dropping the electrode off.

A hotter plug is used in colder conditions to aid starting or is used on a worn , oil consuming engine which would foul a colder plug.

Phucked with your head enough ??

Cheers

Ken

Originally posted by Micko

Anyway - who cares...

ZACHARY !!

I sure as shit don't sherlock.

Though if that spanker next door with the new loud exhaust on his rex goes belting down the street one more time....

Cheers

Ken

Originally posted by Micko

Right - almost done...

What this is telling me is that I should have gone to an NGK 8 (or stayed with a 7).

Micko , what plug exactly did Steve recommend.

I have checked my reference and Hendo told me to use

BCPR7ES -11 and gap them to .8mm

Cheers

Ken

PS I have and they work fine.

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