spark plug Q
#1
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spark plug Q
I'm running a 509 with 10:1 compression, and Merlin aluminum heads.
I have trouble finding anything better then 91 octane, so I retard the timing a bit, and keep an eye on the plugs. So far everything seems good.
My Q is,
I am about to replace the bosch platinum plugs, and having a hard time finding them locally. So I started reading, and it seems the bosch platinum plugs, and not real well liked, even though I have had good luck with them so far in this motor, and my Mustang seems to really like them as well.
my plug has the # FR8DPX stamped on it. From what I read these don't do well with detonation. Should I use something else?
thnx
-Shane
I have trouble finding anything better then 91 octane, so I retard the timing a bit, and keep an eye on the plugs. So far everything seems good.
My Q is,
I am about to replace the bosch platinum plugs, and having a hard time finding them locally. So I started reading, and it seems the bosch platinum plugs, and not real well liked, even though I have had good luck with them so far in this motor, and my Mustang seems to really like them as well.
my plug has the # FR8DPX stamped on it. From what I read these don't do well with detonation. Should I use something else?
thnx
-Shane
#3
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I'm running an NGK Iridium UR6IX and I'm planning on going to their racing plug with the cut back electrode to reduce the risk of detonation. I would recommend a -6 heat range in NGK. I have an MSD 6M ignition with the MSD Blaster HVC-2 coil, so no worries about fouling.
#6
Charter Member # 55
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I'm running an NGK Iridium UR6IX and I'm planning on going to their racing plug with the cut back electrode to reduce the risk of detonation. I would recommend a -6 heat range in NGK. I have an MSD 6M ignition with the MSD Blaster HVC-2 coil, so no worries about fouling.
Stock Plugs on Merc NA engines are AC MR43T or NGK BR6FS.
The M on the AC is for marine and is really not needed.
#7
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You're absolutely correct, I meant to type a -8 which is what I'll be running. That's what I get trying to eat lunch and read forums at the same time.
#8
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I've always ran r43t in everything else, and since I'm a "if its not broke, don't fix it" kinda person, I think I'll just go back to the AC delco's but run a 42.
#9
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Join Date: Aug 2010
Location: Annapolis, MD
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I tried Bosch platinums in my 03 Cobra. Ended up detonating and blowing the plug out of the number 1 cylinder. Had it timeserted and ran cooler NGK plugs after that.. Liked NGK a lot better and worked a lot better. I know this was on a car, but still not a fan of Bosch platinum..
#10
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Well I should have done some checking before I bought the r42t's. they are different then the bosch platinum plugs that are in it now. I was worried about hurting something, so I didn't install them. The bosch plugs seemed like they were longer?
Head work was done by Jim V, and I have the paperwork at home.
Can anyone tell me what plugs i should use?
Heads are Aluminum Merlin. # WOR 014C
Head work was done by Jim V, and I have the paperwork at home.
Can anyone tell me what plugs i should use?
Heads are Aluminum Merlin. # WOR 014C