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Thought I'd better share a tip from nncoolg that some may not know with spark plugs for EA82T and NA mpfi. I have always used NGK spark plugs after discovering their design ran cleaner than some souced from a German manufacturer, so speak NGK.

I have always bought BP6ES or colder BP7ES and their 1.1mm gap mates the BP6ES-11

Also struggled getting them in and out due to my 13/16" spark plug socket binding against the head casting until I bought a thin walled socket sold more as a motorbike tool.

Better still is to use spark plugs with the smaller hex size rated as 14mm - the 13/16" ones are rated as 18mm. Bloody obvious choice to those aware you can make some changes to the plugs dimensions without altering the important spec stuff. I wasn't.

NGK for eg with 18mm are BP6ES, BPR6ES-11, the smaller hex plug part number is simply found with a BCP6ES-11 where the 5/8" plug socket fts in without any clearance issues. I got some of the more common BCPR6ES-11 today. Not sure if simpler plugs are available easily or at all, BCP6ES may not exist.

Happy days

Awesome tip there Steptoe,you must have known my RX has been misfiring the last couple of weeks and needs new sparkies.I have a spare MPFI engine in my touring wagon i was tempted to borrow the plugs out of ,but after reading this i think i will avoid that clearance issue and have a look for the smaller hex size versions,thanks again.

EJ20 and 25 DOHC engines use these smaller hex spark plugs