NGK spark plug codes

[Quickstep192]

Anybody know the difference between NGKBPR6ES and NGKBPR6FS?

Perhaps more importantly, are they interchangeable?

[Locker537]

I think ES has a removable terminal and they are different overall height and reach.

I run BPR6ES in my 3.0.

https://www.ngk.com/ngk-7131-bpr6es-nickel-spark-plug

https://www.ngk.com/ngk-2623-bpr6fs-nickel-spark-plug

[Flat Six]

Not interchangeable.

If for your P-car, you want the ES (0.75 inch reach) not FS (0.46 inch reach). More importantly, the FS uses a tapered seat, not the flat seat plus crush washer found on the ES.

[safe]

What you really want the BCPR6ES, same plug only smaller hex so you can fit a generic sparkplug tool much easier down the head.

[Wasatch 911S]

Probably more than you eve wanted to know about NGK plugs, but helpful with subtle differences.

https://www.ngk.com/ngk-spark-plug-numbering-systems