13 5.7 spark plugs

[kyleyou17]

Hello, got a cammed 5.7. Making 500HP at the wheels. Looking to upgrade the spark plugs. Currently have NGK LFR5AGP, these seem to be an stock plug. Only 40k interval. Looking to upgrade to Iridium IX. Thanks in advance for the recommendations.

 

[Harley Harrold]

 

[Wild one]

Hello, got a cammed 5.7. Making 500HP at the wheels. Looking to upgrade the spark plugs. Currently have NGK LFR5AGP, these seem to be an stock plug. Only 40k interval. Looking to upgrade to Iridium IX. Thanks in advance for the recommendations.

That must be one hell'va a cam to make 500 rwhp,or you were on a very happy dyno. That's roughly 200hp more then a stock truck makes at the tires. Lets see the dyno sheet. I run Denso 3381's gapped at 0.030" on my nitrous'd truck,and change them at no more then 30,000 miles.

 

[Bigskyroadglide]

I run these gapped at .33 on my supercharged truck. I'm at 30k change intervals. Anxious to see your dyno results.