NGK B6ECS instead of 7???

[BIGMIKE1]

Just changed spark plugs, HT leads, extenders, rotor arm and distributor cap. All as precaution just because they looked pretty old and found I had 6's fitted instead of 7's Ive searched on here and read the 6 is a lower temp but just wondered out of interest why anybody would have fitted these and is there anything else I should now check because they were fitted(timing,etc) not driven the car since fitted these tonight. I'll check it drives ok tommorrow but just thought I'd see if there was an obvious reason for this or was it just down to cost???
Mike

[Simon says]

BIGMIKE1 said:

Just changed spark plugs, HT leads, extenders, rotor arm and distributor cap. All as precaution just because they looked pretty old and found I had 6's fitted instead of 7's Ive searched on here and read the 6 is a lower temp but just wondered out of interest why anybody would have fitted these and is there anything else I should now check because they were fitted(timing,etc) not driven the car since fitted these tonight. I'll check it drives ok tommorrow but just thought I'd see if there was an obvious reason for this or was it just down to cost???
Mike

Probably just convenience,don't worry to much NGK have a very wide heat range unlike most of the other crap thus far more accommodating heat wise just enjoy

Edited by Simon says on Thursday 30th June 22:52

[Pupp]

The 6 is actually a 'hotter' running plug than the 7 (ie it is softer and will be less prone to cold fouling). May have been selected to counter fouling issues if the car is/was gently driven and/or if something on the fuelling isn't/wasn't quite right, or maybe just because 7s weren't easily to hand.

[blitzracing]

Just have a look at the colour of the insulator. It should have a nice even brown colour to it. If its pure white then all the carbon has burn off, and the plug is too soft (ie the plug number is too low and its running hot) but this is pretty unlikely with a 6 in day to day use. Conversly if its very dark brown/ black then the number is too high and the plug is running to cold, and the carbon is building up, but there is a pretty wide range between these two. In terms of engine operation, over cold plugs foul up and can make the engine mis fire and hard to start as the carbon builds up, and over soft plugs can cause pre ignition as they act as hot spots in the combustion chamber, and taken to extreme can damage the engine.

[BIGMIKE1]

All 8 plugs looked pretty good to be honest, they were all probably very slightly black but it had been started and stopped a few times to move in and out the garage so Im pretty sure thats why. I was just checking incase there could be an underlying problem and people fit 6's as a way around something.