Going boost...issue with iridium spark plugs?
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Going boost...issue with iridium spark plugs?
I purchased an inlinePRO turbo kit on my S2000. I also ordered some NGK 7173 spark plugs. The shop that is doing the turbo install told me today that iridium spark plugs have caused problems on boosted Hondas/Acuras. I did a search on this forum and it seems like most boosted S2000s are running 7173s.What is your opinion?
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Non-resistor plugs like the NGK 7173 are not recommended for use on our car, HOWEVER some people have been using these with no problems including me. Instead NGK and AEM reps recommend NGK BKR7E resistor plugs for FI S2000's up to 400hp, and NGK BKR8Eix above 400hp.
The Denso iridiums had some breakages in FI S2000's, something about a bad production batch I think, and after that a lot of FI guys on here moved away from Denso plugs and iridiums in general.
I've been using 7173's at 7psi turbo and a .034 gap without trouble, but haven't driven much lately either. I'm going to give the BKR7E a try for the hell of it and if they work I'll stick with them. Cost isn't a problem because they are the same so I figure why not:
http://www.sparkplugs.com/results_cross.asp?pid=7173
http://www.sparkplugs.com/results_cross.as...KR7E+&x=68&y=16
Also, this is from NGK's website (copied from a post made by geists2k):
The Denso iridiums had some breakages in FI S2000's, something about a bad production batch I think, and after that a lot of FI guys on here moved away from Denso plugs and iridiums in general.
I've been using 7173's at 7psi turbo and a .034 gap without trouble, but haven't driven much lately either. I'm going to give the BKR7E a try for the hell of it and if they work I'll stick with them. Cost isn't a problem because they are the same so I figure why not:
http://www.sparkplugs.com/results_cross.asp?pid=7173
http://www.sparkplugs.com/results_cross.as...KR7E+&x=68&y=16
Also, this is from NGK's website (copied from a post made by geists2k):
It is strongly recommended resistor spark plugs be used in any motor that has on-board computer systems to monitor or control engine performance. Use of a non-resistor plug in certain applications can actually cause the engine to suffer undesirable side effects such as an erratic idle, high-rpm misfire, engine run-on, power drop off at certain rpm levels and abnormal combustion. Resistor plugs are also recommended on any vehicle that has other on-board electronic systems such as, two-way radios, GPS systems, depth finders or whenever recommended by the manufacturer.
If you have an outboard marine CDI (capacitive discharge ignition), (such as Johnson and Evinrude), make sure to use a plug with an inductive type resistor (such as a Champion Q-type or NGK Z-type). Use of non-inductive resistor type plugs on these motors can create an open circuit within the spark plug (it will become a dead plug).
Mallory, MSD, Crane and Accel also produce a high output ignition CDI system, however, these should not be confused with a marine style CDI as mentioned above. For an automotive high output CDI system it is imperative you consult that manufacturer for plug specifications for their system. Some high out put systems specify the use of resistor plugs, while others will fry the internal plug resistor turning its 5k ohms into 60k ohms.
As a rule, performance is in no way impaired by resistor spark plugs. The only exception to this may be some models of high output CDI specify non-resistor plugs.
If you have an outboard marine CDI (capacitive discharge ignition), (such as Johnson and Evinrude), make sure to use a plug with an inductive type resistor (such as a Champion Q-type or NGK Z-type). Use of non-inductive resistor type plugs on these motors can create an open circuit within the spark plug (it will become a dead plug).
Mallory, MSD, Crane and Accel also produce a high output ignition CDI system, however, these should not be confused with a marine style CDI as mentioned above. For an automotive high output CDI system it is imperative you consult that manufacturer for plug specifications for their system. Some high out put systems specify the use of resistor plugs, while others will fry the internal plug resistor turning its 5k ohms into 60k ohms.
As a rule, performance is in no way impaired by resistor spark plugs. The only exception to this may be some models of high output CDI specify non-resistor plugs.
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From: Springfield, VA
Originally Posted by 2QYK4U,Nov 17 2006, 12:47 PM
How about the NGK BCPR7ES (NGK 3330) spark plugs? These are the plugs inlinePRO runs on their turbo S2000s.
We run this in our street car, that makes 500+rwhp.
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From: Raleigh, NC
I thought that the NGK 7173's were copper? 
A ton of people use the NGK #7's and the #9's (I forget the whole part #), but they are 1 and 2 steps colder than stock. I have been using the #9's since I went turbo with no problems. I just swap them out every other oil change.
A ton of people use the NGK #7's and the #9's (I forget the whole part #), but they are 1 and 2 steps colder than stock. I have been using the #9's since I went turbo with no problems. I just swap them out every other oil change.