Spark Plugs - SP519 vs SP534
Here is the way I understand it:
The SP519 is the correct plug for the 5.0 under normal (stock) conditions. It comes gapped from the factory at approx. .051. Many guys are gapping down to .045, especially if running a tune. There is some variance in the manual depending on what year your truck is, but .045 seems to be widely accepted as a good number.
The SP534 is the correct plug for the ecoboost under normal (stock) conditions and comes gapped from the factory at approx. .030, some gap them down to .028. Apparently this plug is also recommended if you are running forced induction on your 5.0
Here is my question - is there any difference in these plugs other than the gap, such as heat range? Further, can the SP-534 be ran in the 5.0 without a supercharger? I'm not sure you'd want to try and open the gap from .030 to .045 without breaking the tip, right?
Honestly, the reason for asking is that I was shipped the SP-534s and trying to decide if I mess with them or send them back for the SP-519s. I run a 5* 93 tune with LT headers and an intake.
If anybody has any lessons learned, further or corrective information, I'd greatly appreciate hearing it.