I'm using an US PFC on my Euro-spec FD.
What octane number is the US PFC tuned for, and can this be changed?
The reasen I ask this is that I only use 98octane, and I guess that the car should be tuned for that.

Thanks

 

Normal USA high octane gas is 92-93 RON. If you have access to 98RON, then you could run either more idnition advance or leaner AFRs. I personaly would go for leaner AFRs. It all depends of your engine mods.