| Author | Message | ||
     Nigel Ralph Unregistered guest Posted From: 203.87.62.169 |
Hi All, I'm just wondering whether I should change my spark plugs to compensate for the lower octane fuel currently available. 100 octane fuel and NGK BP5ES are recommended for my '74 Shadow but if super now only rates at 97 Octane should I be changing my plugs to something hotter? My engine is quite worn and my plugs do gunk up quite quickly. My engine rebuild is 2 or 3 years away. (Message approved by david_gore) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 365 Registered: 4-2003 |
Plugs should not be aprticularly related to octane, but if your plugs foul you may safely switch to NGK BP4ES, that's one grade hotter. NGK are normally very good in the fouling department and have a fairly wide heat range. | ||
| Bill Coburn Grand Master Username: bill_coburn Post Number: 258 Registered: 4-2003 |
I have yet to try this Nigel (and Richard) but one of my favourite Gurus has recommended BR4ES on a Phantom that left to its past performance would probably initiate NGK setting up a factory in the Australian Capital Territory. And I instance 50 miles for a plug's life. Avoiding the obvious solution to throw the engine away and install a new one, I have fitted new valve seals (complete with spring locating washers), decarbonised it chemically which hopefully will unglue the rings from the bottom of the piston grooves, installed the correct needles in the carburetters (part of a complete overhaul)and moved the ignition timing from five degrees after TDC to five degrees before TDC! We have yet to fire the old girl up after these very personal attentions but I live in hope. I had run BP4ES as Richard suggests rather than the recommended BP5ES and they did last longer but apparently the BR4ES have a shorter centre electrode and crud up slower than the ones I have used. As usual I am suprised as I would have thought sticking the electrode further into the combustion maelstrom would have stopped any deposit from surviving there! But then I note that there are well over ten thousand patents on spark plugs so perhaps there are brighter people out there that know more about these things than this ageing amateur! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 368 Registered: 4-2003 |
Bill, If you have a long term budget plan, go for BPR4EVX. Although I have a spare set on hand, after 50,000km mine are still like new and have not chosen to change them. They cost a lot more than ES plugs, but seem to last forever and never soot up. Sorry about the Canberra spark plug manufacturing industry ! B=14mm P=projected insulator type R=resistor conductor 4=heat (2 hot, 11 cold) E=19mm reach VX=high performance platinum | ||
| Nigel Ralph Unregistered guest Posted From: 203.87.64.230 |
Thanks Bill and Richard. I shall step up a heat range and go to the 4 rating as you suggest. I had thought that with the lower octane rating a hotter spark would be needed but was uncertain about any other consequences. (Message approved by david_gore) | ||
| William H. Trovinger II Grand Master Username: bill_trovinger Post Number: 159 Registered: 8-2003 |
Richard; Can you tell us (me) the difference between the GR4IX and the BPR4EVX? Seems the site I order my plugs from says that this one is superceding the latter. Regards, Bill | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 369 Registered: 4-2003 |
Bill T. I was not aware that the plugs have been superseded, but do know that the GR4IX is a suitable plug. You are probably correct: why would NGK wish to continue the old product ? The IX suffix shows that the GR4IX is an NGK Iridium plug. NGK make a BPR5EIX iridium plug, but I do not believe that there is a BPR4EIX. The GR4IX makes sense in that light. BPR4EVX is a high performance platinum plug. The original R-R plugs are cross-referenced by NGK to both BPR5EIX and GR4IX iridium plugs, so you are probably correct. I have no idea what the G prefix means. This is opening a can of worms which I didn't really want. | ||
| William H. Trovinger II Grand Master Username: bill_trovinger Post Number: 160 Registered: 8-2003 |
Richard; If I read NGK's site correctly the G stands for "14, 19mm (3/4") Reach, 2.6mm (13/16" Hex." Whatever, that means I am not certian.  Best regards, Bill | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 370 Registered: 4-2003 |
They are the exact same size as a BxES, BPxES, BPRxES or BPRxEVX etc. B means a 14mm thread diameter, the most common at least in years gone by. E means 19mm reach, that is how deeply the plug screws into the cylinder head. Why they changed to a G prfefix for some iridium plugs beats me. Although Crewe did not change the replacement interval for the platinum BPR5EVX etc, they come out looking like new after any mileage. I can't imaginy plug outperforming those Platinum plugs, which reach the bin in new condition. Iridium may well be better though, and they do cost more than platinum plugs, but only CAN$0.50 in the case below. See the following links. There is even a cross-reference table: http://www.clubplug.net/canada/retail_iridium_ngk.html http://www.clubplug.net/canada/acdelco_ngk_iridium.html http://www.clubplug.net/canada/retail_vx_ngk.html | ||
| William H. Trovinger II Grand Master Username: bill_trovinger Post Number: 161 Registered: 8-2003 |
Richard; Thank you for the explanation you made it easier to understand. Advance Auto wants U$5.99 for the platinum and U$6.99 for these iridium ones so at only a buck more I will give them a whirl. Regards, Bill | ||
| Nigel Ralph Unregistered guest Posted From: 203.87.65.25 |
Have replaced the old plugs with BP4ES and have put some total fuel system cleaner through the tank. The engine is now murmering quietly away. I hope to get it purring one day! The iridium plugs were only available on order and cost just under $20 each. Many thanks for your advice. (Message approved by david_gore) |
