Denso plugs?


Active Member
Oct 30, 2018
Anybody run the Denso W16FS-U plug in a HT motor? It's a U-groove plug. The "16" may be too hot. But dimensions are correct.
I bought one along with a couple of NGKs* to try out.

My stock plug is already leaking badly between the body and insulator. Big brown blow-by stains on the outside of it.
I'm not going to try this Denso plug 'til I've tuned everything in with either a BR6HS NGK or a B6HS with resistor cap.
Then I'll try these others as I need them.
I was just curious about the Denso plugs though. I've always had good experiences with N-D (Denso) plugs and parts in my Toyotas.

*One odd-ball plug I bought was an NGK R5674-8 racing plug. The reach is only 7/16" or 11mm, so it's just a tad short.