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I am installing a BWR Supercharger. I want to change the spark plug at the same time. So what spark plug should I use?
 

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When I installed the VF kit I went with one range cooler iridium plugs. Part number was NGK Iridium IX BKR7EIX-11. While it seemed safer, the engine was sluggish at idle. So using a trick I learned from previous forced induction cars I went back with the stock plugs, but I gapped them down 0.035" (from stock gap of like 0.050"). The engine idle'ed good again and I didnt worry about spark blowout, which becomes a bigger problem as boost and RPM increase.
 

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+1 for the NGK Iridium IX BKR7EIX-11.

I have the BWR SC with PES tune and these plugs have been great. No stumbling, smooth idle.

Regards,
Wayne
 

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+1 on the NGK Iridiums, cost more than regular plugs but absolutely worth it. Just out of curiosity is it even possible to regap iridiums without causing damage.

I just plugged them in and the car ran/started fine albeit a slightly higher idle.
 

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Just out of curiosity is it even possible to regap iridiums without causing damage.
Ya you just have to do it by pushing the ground strap against something very carefully and close the gap. Dont go too small cause you dont want to open it up by prying against the electrode.

I usually push the spark plug against the concrete floor of my garage, since its hard but wont mar the surface cause its smooth.
 

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You should generally only change the plugs to a different heat range if the current heat range is posing a problem, i.e. appears to be too hot or too cold;). Standard gap for all the current blower systems available is sufficient. With Gap, bigger is better up until the point the spark cannot make the jump. Standard gap (the gap the plugs come with) isn't a problem-- even at 285whp and 8500rpms...

Iridiums are nice for longevity but make no appreciable excess power than their cheap copper core cousins. If you're simply trying to determine the correct heat range for the car, buy the cheap copper versions (of the same brand) for testing/tuning purposes. Once the correct heat range is determined, go buy your expensive iridium plugs that will last 50-100K miles...

FWIW- I still have copper plugs in my car and she runs okee-dokee:D

Best,

Phil
 
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