Spark Plugs.

[nodbe]

Hi Guys,

Anyone know owt about NGK BP7EV or BPR7EIX plugs ( or the Champion equivalent ) ?

[andyhodg]

Hi

I am trying the iridium plugs for the first time. Only about 80 miles with them at the moment but all is good. Response seems a bit sharper but I can't really tell.

I changed to these as the standard NGK plugs were fouling occasionally which was a nuisance. I'll try to keep you posted.

Regards

Andy

[nodbe]

Hi

I am trying the iridium plugs for the first time. Only about 80 miles with them at the moment but all is good. Response seems a bit sharper but I can't really tell.

I changed to these as the standard NGK plugs were fouling occasionally which was a nuisance. I'll try to keep you posted.

Regards

Andy

Thanks Andy,
Had the same problem with fouling.
Will be grateful if you keep me posted.
Ernie ( NODBE ).

[prezoom]

I have been using BPR6EIX plugs in my Elan since 2007. Same plugs, and every time I pull them out, they look just fine. Never have a fouling problem and the car starts immediately. Wouldn't use anything else.

Rob Walker
26-4889

[twincamman]

I changed from n9y champions to ngk 6 . they work well with only a slight miss as they clean off at 80 and 90 mph ----ed poor spellers of the world untie

[rgh0]

The fancy and expensive plugs were devleoped for extended life as dictated by pollution regulaltions which require plugs to last much longer than previously. With modern fuel injection systems and unleaded fuel the life of a plug is dictated by electrode erosion thus the use of more expensive electrode materials and design.

The risk with using them in an Elan is you dont get that extended life as the life in an Elan is usually dicated by plug fouling and insulator failure from fouling with the poor mixture and plug temperature control in a carb engine, if using leaded fuel this also can reduce plug insulator life due to lead deposits.

Whats important is get the heat range right for your enigne - typically a "6' heat range plug in NGK is the right range for a road twin cam unless you live in Germany and spend all your time at 6000 rpm on the autobarn in which case a "7" plug is probably better. If you race a 8000+ rpm high compression twin cam then you probably need a "8" plug.

With the right heat range you will get maximum plug life possible but it will still probably not be dictated by electrode erosion and it will be much less than the 80 to 100 thousand mile design life these plugs are intended for so you still probably dont need the fancy plugs. But using the fancy plugs once you have the heat range right probably will not hurt either except in your hip pocket.

cheers
Rohan

[pauljones]

Hi all,

I use super 4's in my plus 2,i changed because of the fouling issue and that was after trying a few different numbers.In my opinion these are good plugs,Why?. I just seemed to get better throtle response,they stayed cleaner for longer and less maint required.When I swaped from points to ignitor 2 electronic style,the spark was fantastic.I did swap and put in the 6's but the spark didnt seem as bright.I cant explain why,it was only a plug change,gap was correct too.

Paul

[nodbe]

Thanks Guys,

Got some nice shiny new NGK BP6ES's.

Anyone know the best gap to set please?

Nodbe.

[simonknee]

Standard Coil: .020" - .025" (I'd head for the later)
Lucas Sports Coil: .040" - .050" (and other high output coils too)

Some folks report .030" - .035", not sure why.

There's a bunch of threads to confuse you on this - read them at your own risk!

[rgh0]

Use the standard 20 to 25 thou gap, the NGK's should come set at that gap and I normally never have to change them.

The larger gaps some people use with higher voltage output coils may or may not help. From an engine ignition perspective once the fuel is ignited it is ignited and the spark from a 20 thou gap is fully sufficient for a well tuned twin cam under all operating conditions as far as i can tell both on the road and on the dyno. The coil operates up to the voltage required by the plug gap if its capable. A wider gap increases the voltage required to generate the spark and this puts all the high voltage components under more strain from an insulation breakdown view point. The original Lucas cap and rotor struggles to accomodate higher voltages than what comes from a standard plug gap without the high voltage finding the wrong path to earth.

cheers
Rohan