Expensive performance plugs r a rip off. Shud it b found that a modified engine is having ignition probs , and I can assure u that this won't b an issue until the engine is making BIG numbers , then it's the temp range of the plug and the HT voltage that will require attention.
Anything below 450 brake u wud b ok on standard type plugs of the correct heat range , this being determined by the fuel setup of a particular engine.
had problems with standard plugs on my 7 as the car runs 1.4bar. i am using NGK BR8EVX and every thing is running very well. will definitely recommend them to anyone. i am also runing 0.6mm gap. these are the same ones rallyart run in their extreme and extreme s engines. so they could not be that bad.
never even bothered to check the gap just screwed them in
I AM USING RALLIART PLUG LEADS, these do make a difference
increase spark energy by 30%, 0.9kohm/metre vs 16kohm/metre!!
plug colour fine, have been complemented on this
heavy gsr with long gearing
boost above 1.6 at all times
car takes 9.5 seconds to 100mph with normal take off
best 4th gear 2000-7000 time 11.75, worst 12.25
best 4th gear 3000-7000 time 8.25, worst 8.75
more than 20 runs at different places/times within these figures
using datalogs NOT stopwatch for times
will go faster with more fine tuning of ignition and fuel maps, cam timing and second jet on the aquamist
rarely 'cruise' however, i like to get there (nz si roads help too)
I'm running 340 brake on standard plugs no problem , heat range wud probably need attention at 380'ish brake , this is the point larger injectors and fuel pump r needed .
However evotrak is doing well on standard plugs and I wud say from his numbers his car is producing over 380 brake.