Sixes and Sevens

[jr6yam]

A spark plug question;-
I'm going to change to NGK iridium plugs, but I'm not sure whether to
stick with the 7 heat rating or drop to 6

The car is a standard 4L chim (serpentine)
Plugs 1 and 2 have a light brown deposit on the Electrode with some light carbon
build up on the plug edges

Any advice/wisdom gratefully received

John

[Ribol]

Those plugs were originally brought out for modern cars that run higher temps due to leaner mixtures and with extended service intervals, as in 30,000 + miles in between services.

Not too sure what there is to be gained on a old school standard car with an annual/6000 mile service interval like ours.

[jr6yam]

Just thinking a better spark is always a good thing
I know it's not the same thing; but iridium plugs made a difference to my motorbike

[Ribol]

No down side to a better spark, iridiums with a larger gap will hopefully give you that as long as the rest of your ignition system is in good nick.

Give them a go and let us know how you get on

[Simon says]

Cant see how a stock RV8 is going to exploit the use of Iridium plugs, dont bother pissing about with heat ranges as NGK have a very wide heat range anyway and with everything being equal the stock TVR fitted plUg range plug does not foul in normal use, although i prefer the NGK extended tip plug in the RV8 i.e BP7 ES

[Ribol]

Simon says said:

..........i prefer the NGK extended tip plug in the RV8 i.e BP7 ES

That is only because they are classed as bulk plugs by NGK and cost less trade, you tight wad

[Simon says]

Ribol said:

Simon says said:

..........i prefer the NGK extended tip plug in the RV8 i.e BP7 ES

That is only because they are classed as bulk plugs by NGK and cost less trade, you tight wad

You've rumbled me ya bugger. is it not past your bed time? actually the ECS plugs are not any dearer when purhased in 10's well pennies really.

Edited by Simon says on Saturday 7th July 00:40

[dnb]

I find the resistor version of the above plug works best in my TVR. (And it's cheaper than the standard plug too)

It should be noted that the plugs specified for the last year of P38 Range Rovers was an expensive platinum tipped affair. Land Rover must have had a reason.

[Simon says]

dnb said:

I find the resistor version of the above plug works best in my TVR. (And it's cheaper than the standard plug too)

It should be noted that the plugs specified for the last year of P38 Range Rovers was an expensive platinum tipped affair. Land Rover must have had a reason.

Yeh, extended service intervals inc the better wasted spark ign system to exploit this type of plug I would def recommend using R plugs in anything running anafter market ECU,s I have to