| Author | Message | ||
     KC Unregistered guest Posted From: 168.210.90.232 |
I would appreciate advice on the following. I am about to change the spark plugs in my 1970 Shadow 1. It is an early car with the 6.2 motor. This forum advised me to use NGK BPR 4 EVX, but this is not available here in South Africa. My local RR dealer uses Champion N12YC, and my manual quotes Champion N14Y. The NGK equivalent for both these part numbers is BP 5 ES, which I bought. My question is, are these plugs suitable for my car, and if so, what should the gap be? Regards KC | ||
| Robert Chapman Prolific User Username: shadow Post Number: 43 Registered: 5-2003 |
Hi KC. The spark plug BRP4EVX is a platinum electode type suitable for late model cars. NGK5ES are OK for your car and the gap is .025in or .6mm. If your engine is high mileage or you travel mostly short trips you can also use NGK4ES,these are equivalent to CHAMPION N16YC. | ||
| John Dare Unregistered guest Posted From: 144.138.194.96 |
KC. What the handbook states is relevant to an engine in a new or reconditioned state. I also have a nice 1970 S/Shadow (SRH 8058) with approx. 130k miles recorded. Not suprisingly there is some (not much!)engine wear such as valve guides and their seals (the latter recently replaced) together with some piston ring wear. All of this is to be expected, however with more oil finding its way into the combustion chambers you need a slightly "hotter" spark plug to burn off any excess oil which permeates the "normal" air/fuel mixture. The esteemed Robert Chapman (Automtive ENGINEER!) put such plugs into my car at its last service and it has NEVER run better. Check with him for brand and model/heat range number. He knows all that which the so-called world "authorities" remain blissfully UNaware. I thought I knew something about cars but when you talk to a REAL expert one realizes how little one really "knows". As an aside, but for illustrative purposes, I installed a "full" stainless ("last a lifetime" etc) muffler on my 1972 "Porsche" 911S (arguably one of the finest production sports cars ever built) approx. 10 years ago, but it never really seemed to perform as it had previously. My local "Porsche" expert (of similar professional standing to Robert Chapman) told me that the non standard muffler (as fitted) did not provide enough back pressure, something I was totally ignorant of and still fail to fully understand. However,I fitted a new "factory" muffler (A$1000 approx.) and the car now runs better than ever, just as my S/Shadow now does. Moral; take advice from REAL experts!. | ||
| KC Unregistered guest Posted From: 168.210.90.232 |
Hi John Mine is SRH 8475, so it must be identical to yours. The mileage on my car is very low for it’s age, it has just clocked 90 000 km (56 000 miles). I have most of the previous two owners records, so this mileage can be substantiated. I intend driving the car a lot more often than they did. In the last 12 months I did 10 000 km’s. Thank you for the advice on spark plugs. As for Robert, I have a file full of his posts, which I print for future reference  This forum has been a great help in maintaining my vehicle. Regards KC | ||
| Serge PONTES Experienced User Username: serrgio Post Number: 10 Registered: 1-2004 |
Hi Robert, I'm interresting on your answer to KC because I have to change my spark plugs too and in France, champions N14YC oy N16YC aren't avaible in all places; NGK are eften easer to find. but in France, we always do have letters after the "NGK" and in your text, you only said that KC could use "5ES" or "4ES"....when I've got in the seller, many references have 5ES or 4ES end and different combination of 3or4 letters before...could you tell me if you know wich will suit my SHR22789 (shadow 1 from 1975) thanks !! by serge | ||
| Robert Chapman Prolific User Username: shadow Post Number: 46 Registered: 5-2003 |
Hi Serge, BPR5ES OR BPR4ES are the plugs you need. | ||
| Serge PONTES Frequent User Username: serrgio Post Number: 11 Registered: 1-2004 |
Many thanks Robert; your very quieck and kind answer will permit me to try to change them this afternoon...and so if weather will be better in paris, going to picnic tomorrow or friday ! have a nice end of week ! by serge | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 84 Registered: 3-2005 |
Hello Robert, you said: "If your engine is high mileage or you travel mostly short trips you can also use NGK4ES,these are equivalent to CHAMPION N16YC" I have recently changed the spark-plugs in SRH3430, for tha same that it had plugged: Champion N12YC. The old ones had a very small carbon deposit, but electrodes were clean and lookd as new. Just the porcelain white sealant has some grey colur in the nearer area of the motor. I do not know if it could be a overheat symptom. These spark plugs are colder that the suggested N14YC by RR on its hadbook. I suspect that SRH3430 has a very high milleage on its motor(from the documennts provided by RREC, i saw that just 3 years after its date of first bought, was sold to other owner with 120.000 Km, and this was 34 years ago!) , but it has a regular are efficient run, iddle speed, good and fast starting. It has a low oil consuption, but some leaks on the garage floor. Also, and as all you had could read in this forums, it suffer a little high motor temp also in summer. Would work better with the hotter N16YC that you suggest for high meilleage motors? I wonder if you could please ilustrate to us who are not experts how high milleage motors needs different thermic grades in the spark-plugs. i think it will be really interesting. I allways has asked myself how so different motors form different brands recommends the same spark-plug when i think that conditions inside each motor were so differents. It will also apllies with different wheather and lattitudes, i think. |
