Spark plugs

[Choosing a name is hard]

I have a set of Bosch plugs and the gap is a lot smaller than the plugs I have taken out pics of new and old plugs
Old plugs are Denso
Also do the old plugs look ok as the ends are very black

 

[Roscobbc]

Old one appears to be extended tip and as you say is very sooty/oily. Is it correct for the car? - do you have an oil consumption issue? - is the 'new' plug correct for the car? - irrespective of anything plugs should always be 'gapped' to the correct spec' (even if they are supposed to come with correct gap)

 

[teamzr1]

Hard to answer as you do not mention the year, model and engine

If this is a stock C5, the stock Gap is like 0.70, your gap looks a lot wider and should be replaced
I suggest using like a NGK-TR6, they are one step colder and gap like, 0.35 which gives a better idle

Do not take a plug designed let's say at 0.35 and bend them to be 0.70 as that changes the arc of flame and crappy burn of air/fuel
Same if designed for 0.70 and bent down to be 0.35

With that wide of a gap than of course flame is weak and cause black crap as that or issues such as
dirty aircleaner, MAF or fuel injectors.

 

[Choosing a name is hard]

Old one appears to be extended tip and as you say is very sooty/oily. Is it correct for the car? - do you have an oil consumption issue? - is the 'new' plug correct for the car? - irrespective of anything plugs should always be 'gapped' to the correct spec' (even if they are supposed to come with correct gap)

No idea on the oil consumption as car is new to me

 

[Choosing a name is hard]

I must admit I did wonder if whoever designed where plug 7 goes has ever seen a human / is aware what shape a human is . My hands are in bits from trying to get that bloody plug in . 1-6 and 8 no problem but it took longer than all the rest added together just to get that one in

 

[plastic orange]

NGK TR6 plugs are not listed in the UK, so I was informed the equivalent here is NGK BCPR 6ES. That's what I used in my LS powered Morris Minor when a low mileage expensive Denso iridium failed so I changed them all. You just change them a bit more often. Fortunately, I can do the plugs in my Minor in about 15 minutes.

Pete

 

[Roscobbc]

I use NGK BCP7ES plugs on my modified 489 cu in engine - was originally using a colder '8' range plug - always get fouling issues so went to hotter '7' plug which helped......and oddly this same plug is used on some 'cooking' Puegeot saloon cars from the 1980's.
NGK BCPR 6ES. is a resistor plug and a range hotter than the one I am currently using. NB, you don't really need a resistor plug unless (which is unlikely) you are getting radio interference.