Best Plugs

Post Tue Sep 30, 2014 12:00 am

What's the best running spark plugs for the 1987 325i M30 engine?

Post Tue Sep 30, 2014 7:58 am

M20 not M30 engine? NGK BPR6ES.

Post Tue Sep 30, 2014 8:28 am

As above, every other spec of plugs I have tried has caused some sort of running issue.
Including the recomended zgr5 ngks. They caused a high speed miss I was chasing around for a while.

Never had a single issue with the bpr6es in years.

Post Tue Sep 30, 2014 11:41 am

Thanks for that James. I will see if I can find them here in the Philippines somewhere. It isn't that easy sometimes.

Post Tue Sep 30, 2014 2:14 pm

Bosch W8LCR / Bosch W8LPR were the original plugs used if I am not mistaken.

Post Tue Sep 30, 2014 2:30 pm

Gavla wrote:Bosch W8LCR / Bosch W8LPR were the original plugs used if I am not mistaken.

Yep, the plugs by the same part number you get today seem to degrade quickly and produce an idle hesitation/misfire.

Set of those in my free to anyone that wants them box.

Only thing I can put it down to is 10% eth unleaded vs the zero eth unleaded or 4 star that these would have been running on before.
That and a lot of these cars are now chipped with ageing ignition systems both of which will lower the margins of error available.

Post Tue Sep 30, 2014 2:40 pm

Fair enough...was not aware of that...

Post Wed Oct 01, 2014 3:50 am

NGK seem like a lot better plug than bosch. You can use BPR5ES as well which might suit a lower compression/performance engine as it is a hotter plug. it might suit an engine that does lots of cold starts and doesnt run at full temp often due to short trips.

Post Wed Oct 01, 2014 9:37 am

Gavla wrote:Bosch W8LCR / Bosch W8LPR were the original plugs used if I am not mistaken.

These are for the early high comp engine. They burn to hot for the later.

Post Wed Oct 01, 2014 10:59 am

bosch WR8LC/W8LCR are for low comp engines its a hotter plug than the NGK BPR6ES which suits an engine with a little more compression