Terminal miss-fire issue....again
Thread Starter
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From: Central Florida
2013 Chevy 427 Torch Red
Time will tell but I used this and some vendor recommendations for my decision. These are spec'ed for the car.
An unaltered engine will run within the optimum operating range straight from the manufacturer, but if you make modifications such as a turbo, supercharger, increase compression, timing changes, use of alternate fuels, or sustained use of nitrous oxide, these can alter the plug tip temperature and may necessitate a colder plug. A rule of thumb is, one heat range colder per modification or one heat range colder for every 75–100hp you increase. In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber.
An unaltered engine will run within the optimum operating range straight from the manufacturer, but if you make modifications such as a turbo, supercharger, increase compression, timing changes, use of alternate fuels, or sustained use of nitrous oxide, these can alter the plug tip temperature and may necessitate a colder plug. A rule of thumb is, one heat range colder per modification or one heat range colder for every 75–100hp you increase. In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber.
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From: Vegas and Vancouver, BC
.
Doesn't that mean that whomever has a tune should get plugs one range cooler? Glad you got it sorted out with costing that arm.
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From: 43°38'N / 79°52'W
EuroCharged 2012 C63 BS Coupè
Time will tell but I used this and some vendor recommendations for my decision. These are spec'ed for the car.
An unaltered engine will run within the optimum operating range straight from the manufacturer, but if you make modifications such as a turbo, supercharger, increase compression, timing changes, use of alternate fuels, or sustained use of nitrous oxide, these can alter the plug tip temperature and may necessitate a colder plug. A rule of thumb is, one heat range colder per modification or one heat range colder for every 75–100hp you increase. In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber.
An unaltered engine will run within the optimum operating range straight from the manufacturer, but if you make modifications such as a turbo, supercharger, increase compression, timing changes, use of alternate fuels, or sustained use of nitrous oxide, these can alter the plug tip temperature and may necessitate a colder plug. A rule of thumb is, one heat range colder per modification or one heat range colder for every 75–100hp you increase. In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
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From: Central Florida
2013 Chevy 427 Torch Red
Thanks, I think the word here is would not. It was actually the shop foreman hovering over the car to make sure that anything done would be billed. My SA was in CYA mode (he quit while my car was there) and no one was thinking like a mechanic just blaming the headers for what the STAR was showing. Feels better resolving it yourself anyway. Got two weeks of a free loaner as well.
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Joined: Feb 2009
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From: Sarasota FL
2020 E450 Wagon
These Denso's are supposed to be slightly cooler and they are pre-gapped at 0.43" They had 26,000 miles,many track days and plenty of race fuel used. The same bank had a cam position problem at an earlier time which may have hastened the electrode fouling on those specific plugs.
However, if something goes awry such as a sensor failure, batch of bad or additive laden fuel, glazing and other deposits can occur and misfires will result.
Congrats on figuring it out!
.
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From: Gulf Coast but not Florida
GLK350, SL63 AMG
Warning
For Bosch, a 7 heat rang plug is colder than an 8.
I am led to believe a 7 HR Bosch and 7 HR NGK are more or less comparable as to heat range, all other design features being equal.
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From: San Diego
C63, C300, 911TT x 3, 911 C2 x 2, 911SC, SL65, SL500, 280SL Plus some trucks
You ca't blame the dealer too much. They aren't race mechanics. They are trained to make the car work as designed. They do not always have too much performance experience, if any. They have the parts available to them and nothing else.
Most importantly, if its a warranty issue, they aren't going to get paid for hours and hours of time to chase problems on a modified car.
Jim
Most importantly, if its a warranty issue, they aren't going to get paid for hours and hours of time to chase problems on a modified car.
Jim
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Joined: May 2011
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From: Houston TX
2009 C63 ///Amg
hey hughes so i am getting an mhp tune by the end of the month, does that mean i might as well get some colder spark plugs to avoid any problems? as it could add as much as 95 bhp
Senior Member
Joined: Feb 2009
Posts: 280
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From: Sarasota FL
2020 E450 Wagon
If you are staying on the street with short burst of full load you MAY want to go with one heat range cooler plug.
If you will track the car or spend extended periods of time at full throttle (absolutely nuts on the street!) you DEFINITELY should go to a cooler plug.
Have fun and be safe!
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From: Australia
09 C63
well i just ordered these plugs and k&n filters from that site. Thanks heaps hughes!!!! Also, those plugs are not for sale in Australia. Im currently experiencing a similar problem, but not as bad and only just slightly, since i changed my plugs recently with the factory spec. If i had seen this thread previously it would of saved me a few hundred $$$.
h.
h.
Thread Starter
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From: Central Florida
2013 Chevy 427 Torch Red
Back with a 30 day follow up. Car has had zero issues and is actually running better than before thanks to having fresh plugs and the switch to an MHP tune. I will be at Roebling Road this weekend (provided Emily stays away) and again on August 20,21 so we'll see how lap times are affected. Was hoping to have a track specific tune on the new ECU that I bought but there are some issues relating to immobilizer coding for replacement (spare) ECU's that need to be worked out.
Regarding the original issue, after the plugs were replaced, the codes came back but the car ran much better. The front O2 sensor was replaced even though no specific O2 codes were being thrown and the problem went away completely. Should have started with Mthis' advice at the beginning but I think the issue was combination of several factors and may have began last year with the cam position issue being the first domino.
Regarding the original issue, after the plugs were replaced, the codes came back but the car ran much better. The front O2 sensor was replaced even though no specific O2 codes were being thrown and the problem went away completely. Should have started with Mthis' advice
at the beginning but I think the issue was combination of several factors and may have began last year with the cam position issue being the first domino.
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From: Norte America
MBUSA
Hey North,
How are those SLS plugs running? They are gapped a little differently than stock, not sure if it's a meaningful difference (.039 vs .044) Do you remember by chance how much they were each roughly?
How are those SLS plugs running? They are gapped a little differently than stock, not sure if it's a meaningful difference (.039 vs .044) Do you remember by chance how much they were each roughly?
Last edited by GHAZAN; Aug 2, 2011 at 08:22 PM.
Super Member
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From: UG
2013 ML63 AMG PP
I actually went on sparkplugs.com and ended up talking to a lady from Monarch Products Inc based in California. They didn't have Densos but after explaining my situation with the approx 77hp increase from my tune and what I read in the forums combined with my own experience, they recommended 1 stage cooler NGK sparkplug #6706 instead of the OEM #6043.
However they told me to have them regapped that's why I was asking on the forum otherwise I'll give them a call tomorrow.
However they told me to have them regapped that's why I was asking on the forum otherwise I'll give them a call tomorrow.
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C63 AMG
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Joined: Jun 2002
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From: UG
2013 ML63 AMG PP
Newbie
Joined: Jun 2015
Posts: 9
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2011 C63 2013 GTR
So I have been looking at spark plugs to replace my OEMs
what spark plugs are know to be the better performer out of the bunch?
I know life span should be a little shorter, but which ones should I go for
I also have Kleemann LTs and a tune and I beat on the car regularly
Edit, after some reading, I want to go with Brisk LGS, should I go for heat range 12? and what's the best place to get them from?
-AJ
what spark plugs are know to be the better performer out of the bunch?
I know life span should be a little shorter, but which ones should I go for
I also have Kleemann LTs and a tune and I beat on the car regularly
Edit, after some reading, I want to go with Brisk LGS, should I go for heat range 12? and what's the best place to get them from?
-AJ
Last edited by ASHRAF C63; Jul 28, 2015 at 06:59 PM.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Weistec used to recommend Brisk plugs one heat range colder but are now selling Bosch.
http://weistec.com/all/c/c-63/2012-2...m156-m159.html
http://weistec.com/all/c/c-63/2012-2...m156-m159.html
Super Member
Joined: Jul 2015
Posts: 793
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From: NY
2001 Porsche 911 Turbo (heavily modified)
Are those Weistec plugs suitable for a p31 car with Eurocharged v5? I am getting the knocking/misfiring shakes in my car. Feels like plugs. Do you guys recommend the Weistec plugs or something better or more economical but cooler? I am going RoW boxes soon as well.
