Ok so I emailed NGK about plugs. They emailed me back saying sorry we do not offer any plugs for the supercharged version of the S type??? So now I'm skeptical about using this plug.... Here is what was said:

Hello,

Thank you for your inquiry however we do not offer a spark plug for the supercharged version of the S-Type.

Best Regards,

Rob MacDonald
Technical & Training Specialist
NGK Spark Plugs U.S.A. INC. || NGK Spark Plugs USA
46929 Magellan Dr. || Wixom, MI 48393
OFFICE: 248-926-7104




-----Original Message-----
From: wuzupez@yahoo.com [mailto:wuzupez@yahoo.com]
Sent: Tuesday, March 25, 2014 4:45 PM
To: Info
Subject: [Tagged as Possible Spam] NGK Form Mail
Importance: Low

**** Contact Form & Tech Info Feedback ****

Email From: wuzupez@yahoo.com
VehicleType: Car
Make: Jaguar
Model: S Type-R
Year: 2007
Engine Type: 4.2 Supercharged
Comments: Was wondering what plugs are best for this motor? I have an exhaust & intake on it so also wondered when its time to run 1 degree colder plug? I noticed when I searched for plugs it just said Jaguar S type. With no option for filter. Maybe the 3.0, 4.2, & 4.2 supercharged all take the same plug number? Just wanted to be sure so figured I would ask the pros! Thanks for your time!

 

I then asked if I used the IFR5N10 plug in a 1 degree colder version if this would be acceptable for the supercharged engine, his response:

Hello,

Correct the plugs that we offer are "only" for use in the naturally aspirated engine. Unfortunately I cannot verify that lowering the heat range by one will be appropriate for this application.

Best Regards,

Rob MacDonald
Technical & Training Specialist
NGK Spark Plugs U.S.A. INC. || NGK Spark Plugs USA
46929 Magellan Dr. || Wixom, MI 48393
OFFICE: 248-926-7104

 

Might start a new thread on spark plugs for the STR!