Hi. I found an alternative to standard plugs for the A series engines. These plugs have dual electrodes, just like the NGK BPRE6EK, listed on the Tech Wiki section, but the electrodes on these have U-grooves. I am running these plugs on my A15 and got better acceleration and throttle response. These are DENSO K16TR11. Cheers!

Thanks for the tip, I added them to the spark plug article. DENSO K16TR11 is a 1.1 mm gap (0.044 inch) suitable for Datsun A-series Electronic Ignition.




DENSO K16TR11 is one heat range cooler than NGK BPRE6EK (same as BKR5EK-11). This heat range was recommended for some years of A-series engines and is a great choice.

Either K or W will work:
K = 14mm threads by 16.0 mm hex ISO (5/8")
W = 14mm threads by 20.6 mm hex (13/16")

Yes, the dual-electrode types last slightly longer than single-electrode plugs. Datsun used a 4-electrode plug for this reason, on the lean-burn engines (DENSO K16TR11 was designed for Toyoda lean-burn engines). They work just as well on standard engines, but last longer.



Denso K16TR11 will eventually need regapping or replacement:



A double-platinum plug will last longer.

As a note, any brand new plugs will give better acceleration and throttle response than used plugs. Even new standard plugs. Racers sometimes replace plugs during races if they become fouled. With EFI that doesn't happen so much.

Indexing your plugs also helps a bit to alot as the burn pattern varies otherwise

selecting the spark plug based on the engine compression and fuel being used also helps as well.

Nice !!

will they work on a turbo motor , that's a big gap

If your electronic ignition is strong enough, it works fine. The E15 or Bluebird or other factory Datsun electronic ignition uses a 1.1 mm gap.

They do work pretty darn fine with the matchbox ignition