The Triumph 2000 / 2500 / 2·5 Register Forum

Hi all
Have been running my 1974 2500Tc on NGK BP5ES spark plugs but it doesn't like them On my second set in less than 12 months. It always starts with a slight missfire then get progressively worse, Car is in a good state of tune.
Can anyone recommend a trouble free alternative.
Thanks
Paul

I've always used NGK plugs and had them recommended by a couple of rolling road owners. I ended up using triple electrode ones in my car although there wasn't any real difference, I can't remember if it was a 5 or a 6 though.

What state are the old ones in when they were removed ?

I wonder if you have a problem with the ignition system possibly the coil or perhaps your car would be better with a hotter or colder plug.

Hello Paul,

I think from memory you are running the wrong grade, it should be BP6ES, if I'm not mistaken?

Alec

Yes BP5ES are too hot, BP6ES or even BP7ES would suit better

Yes, I've always used BP6ES with no problems.

MUT

mind you 5's are listed for a 2.5 TC

Hello all
Thanks for the help. This is the plugs that are listed for a 2.5 TC however when I first noticed the miss fire I checked the plugs they were very clean, like it it was running to lean/too hot. I richened the carbs up a touch but made no difference (made it worse I think). I think the other plugs suggested may be an good idea.
Anyone tried the Denso plugs recommended elsewhere?

cheers
Paul

I find the need to replace the spark plugs in my 2000 and Ford Zodiac every 12 months, I'm sure
Modern petrol has something to do with this