Spark plugs
 

Noticed that cylinder one has some oil in the wells of the spark plugs. How much performance does this typically rob for performance. Also side note how often do you guys changed your plugs and do you 1 step colder plugs need a retune??

My car was idling rough and popping misfires so I would asssume the plugs

1. Depends. The more often it misfires the more the loss of power.
2. Normal interval seems to work for pretty much everyone.
3. Why change the type of plug? Unless you have done major power increase work, (more then simple bolt-ons) it's unnecessary.
4. You need to find where the oil is coming from. Oring? Gaskets?

https://themotorguy.com/oil-on-spark-plugs/
https://www.ngk.com/learning-center/...ugs-heat-range

Put the same heat range in the car as what it came with. No need to drop the range unless you are forced induction. Oil in the spark plug hole can cause misfires.