davabran

iTrader: (4)

Car is 07 VQ35HR
I'm starting on my first big upgrade with the Stillen SC. I have the intake manifold off and decided to change the spark plugs while everything is accessible. After searching most people recommended 1 step colder plugs and kept seeing NGK LFR6AIX-11, oops I didn't pay attention and got the wrong plugs for a VHR. I found limitless recommendations for boosted DE but not much for boosted HRs. Anyways i stumbled on a thread talking about NGK new Ruthenium spark plugs. @dkmura listed the OEM equivalent but there wasn't any other plug heat ranges available at the time I think. I searched today and found a plug NGK LKAR6AHX with similar specs but offered in a lower heat range. Would this be a possible option for a SC VQ35HR? Is running stock plugs for 8-9 psi good enough? Or what is a reccommended spark plug from the forum folks?
links below, thanks for reading.

Original Ruthenium plug thread
https://my350z.com/forum/engine-and-...for-the-z.html

The listed oem equivalent is NGK 92274 LKAR7AHX-S Ruthenium HX Plug

• heat range #7
• Thread Size: 12mm
• Seat Type: Gasket
• Resistor Value: 5K Ohm
• Reach: 26.5mm (1.04")
• Hex Size: 9/16" (14mm)
• Gap: .043" (1.1mm)

I found on the NGK website i found NGK 97292 LKAR6AHX Ruthenium HX Plug

• heat range #6
• Thread Size: 12mm
• Seat Type: Gasket
• Resistor Value: 5K Ohm
• Reach: 26.5mm (1.04")
• Hex Size: 9/16" (14mm)
• Gap: .043" (1.1mm)

dkmura

iTrader: (64)

Why not call Stillen and ask for their recommendations?