Thread: Which spark plug - dual fuel carbed 3.5?

Originally Posted by mark2

Its time to replace the plugs. Any recomendations on a plug (type/brand) for a dual fuel V8? I've heard a different heat range from standard is advisable when LPG is run most of the time.......

NGK Iridium, fit once and forget... and yes one range colder is better...

Forget plus 4s etc... all of those are put the C back in Rap

The iridium's are anice plug tho exspensive but do a great job and last for ever im told ...

Tho i have found that runing a 12 volt hi output coil and crane ignition module with optical sensor on the standard dizzy (points) works a treat with standard ngk plugs as the higher output of the coil gives a larger more intense spark and makes starting a lot easyer and the plugs dont foul like before

That was the problem, the old ones kept fouling on petrol (sooting).
Hopefully now that I've sorted out the mixture problem with the SU's the new set will stay clean......
But I cant afford $200 for a set of Iridiums...........

Originally Posted by mark2

That was the problem, the old ones kept fouling on petrol (sooting).
Hopefully now that I've sorted out the mixture problem with the SU's the new set will stay clean......
But I cant afford $200 for a set of Iridiums...........

It will still soot the plugs only way to stop it is to go for the higher output 12volt coil this is whats needed to blast the crap off the plugs and will make it alot beta to start and gain a little econamy

The standard NGK plug is a BP5ES.

With gas I use the PB6ES, and close the gap to 0.7mm.

Doesn't soot, just the standard brown tinge. Actually most of the times I look, it's closer to white!