Spark Plugs
#12
Geronimo36
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Originally Posted by Griff
I run NGK UR5's in my 525SC with a hotter cam and 7.5# of boost. They are the same heat range as the AC MR41T. Never had them foul out, but after a long idle in humid weather they are pretty dark.
#13
Charter Member # 55
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Originally Posted by Panther
Aren't the UR5's an extended tip plug? I think I bought them once but I didn't use them because I thought it would put the plug too close to the piston.
Yes, they have a slightly extended tip. About the same as the AC R41TS. The tip sticks out about an 1/8 inch.
#14
Lakeside Restorations.com
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I believe the S used to stand for stainless for the marine applications. I would start off with the factory gap setting 1 heat range colder if you are looking to err on the safe side. If it runs & burns well leave it alone. If it is a bit to rich widen the gap a little for a hotter spark and or also go 1 plug hotter.. This is all assuming your fuel pressures are correct..
jamie / Lakeside
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#16
Lakeside Restorations.com
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Sorry, My bad.. I usually use the NGK's.. You would be correct that is why the auto versions usually star as R4###
Jamie
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#18
Geronimo36
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Originally Posted by chewy1955
Been looking for the NGK-UR5's but have been unable to find a supplier. Where can I purchase these plugs?
Thanks
Thanks
#20
Lakeside Restorations.com
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Panther is right..
If they can not get them for you give me a shout. I can probably get a set for you if you dont mind the shipping..
Jamie / Lakeside
If they can not get them for you give me a shout. I can probably get a set for you if you dont mind the shipping..
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