Spark plug NGK or AC DELCO

Stick with NGK for plugs, its the OE manufacturer, Bosch or Denso are good second choices. Never touch autolight or champion

Change spark plug to ngk iridium.

they certainly look to be different heat ranges. do yourself a favor and stop going to the dealer for spark plugs. the only different between the dealer spark plug and a big box store spark plug is that one does not come with the VW logo stamped on the side of it. they are otherwise the exact same plug. just go get yourself some new NGK's (all 4) and put yourself at ease.

At least with double iridium ACDELCO on the c5. It’s 100k intervals.

I used NGK plugs in mine. A bit expensive, but they work great and I get 6 litres/100km for fuel mileage.

NGK (Mazda OEM) or Denso are my picks. Personally I think both brands are as good as each other. I buy whichever is cheaper that suits my car.

NGK laser iridiums are the ones I just put in. You don't have to do it often so the price tag doesn't hurt as much I guess is one way of looking at it. Also buying good plugs will help you NOT spend a ton more money further down the road on repairs.

In all the cars, boat motors, and regular lawn equipment I change plugs in… NGK is the best there is.

For the intake i would recommend k&n filters systems, racing plugs are not even worth it, better look it up some NGK iridium

Don't think the platinums give much of a performance advantage and they foul faster if you've got any oil burning going on...