Running 7 Heat Range Spark Plugs

[adam 32]

i had a bit of a pinging problem earlier and decided to run a colder spark plug to bring cylinder temps down.

im currently running 7's gapped at 0.85mm however even after 2-3 days they become fouled. almost impossible to start in the mornings and run like crap for about 5-10minutes.

would this indicate that in fact my car is not suited to running 7's and i should go back to 6's? or is there some adjustment i can make to the spark plug gap? i have a feeling my car just doesnt like the colder heat range plug...

any thoughts?

cheers

adam

[blind_elk]

Probably too cold.

I ran my GTS on 8s for a while. When I decided to go back to 6s, I had the engine idling for very short periods (less than a minute), and when I pulled the plugs, they were black with carbon.

You could try opening the gap a bit to ensure a stronger spark.

[adam 32]

yeh ive opened them up to 0.9mm...

but they still foul really easily and make driving the car when its cold an absolute nightmare.

is there any advantage in running 7s as opposed to 6s? ie by runnings 7s does it actually make any sort of performance difference?

[GTS-t VSPEC]

I would have thought it was only beneficial if your car is driving hard, most of the time it's not, and therefore going back to 6's might be sensible.

[adam 32]

i was just trying to get around the pinging issue (remember paul )

[GTS-t VSPEC]

I think the pinging issue isn't related to the plugs though, have you had the injectors flow tested?

[adam 32]

yeh but it thought itd be worth a try

im gunah put 6s back in tonight i think (unless anyone can suggest otherwise) cos driving the car atm is rediculous

im running injector cleaner through this tank of fuel and see what that does. theres a fair bit of work involved with getting the injectors out so im not gunah rush into the flow-testing idea

[GTS-t VSPEC]

Injector cleaner isn't very good IMHO, doing the injectors should only take a weekend.

[adam 32]

yeh but thats a weekend i havent got

uni semester is coming to an end and ive wasted too much time on the car as it is

[GTS-t VSPEC]

True, Maybe just try and drive it normal on the 6's until you have holidays:D

[adam 32]

yeh i was gunah run 10psi on 6's for the next month. then try some tuning

[rev210]

adam,

If you don't have enough timing advance and don't run highish boost or revs then colder plugs will foul.

7's aren't all that cold, and with RB's the factory ecu like to run 14 AFR's at idle and low throttle so they should stay sort of clean.

My 7's are only a little fouled at the moment thanks to me driving around with a blown ic hose, other than that they are fine.

[Busky2k]

Im thinking of running 7's aswell, considering i've powered up my SR20DET by ~60% over stock. Surely I should go one colder? Cos i read everywhere that ever 75-100hp increase u go 1 range colder. I might just go buy 1 colder copper plug (Heat/R 7) see how it goes. So if it fouls up, at least the car will hopefully still be fine.. Maybe thats an idea for everyone! =)