Aftermarket Spark plug? When should I change?
Thread Starter
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LET C32 2002
Aftermarket Spark plug? When should I change?
Ok this is something the owners manual doesn't say anything about so I wanted to ask the infomative members here...I was wondering when the Denso Iridium IK20 are supposed to get changed?...and I seen a member gap them to (CORRECTION).0035 when the OE spec shows .0039 is there and advantage to that gapping?
Last edited by c32used; Dec 11, 2007 at 12:16 PM.
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
You sure?
oem gap should be the same as the non amg 320 engine .039
http://www.ngk.com/results_app.asp?AAIA=1416912
we go 100,000 mile,your Quick motor someone with the interval amg will chime in.
enjoy the beast
http://www.ngk.com/results_app.asp?AAIA=1416912
we go 100,000 mile,your Quick motor someone with the interval amg will chime in.
enjoy the beast
MBWorld Fanatic!
Joined: Jan 2007
Posts: 3,342
Likes: 11
From: PA
S600, GL450, GLC 43
Ok this is something the owners manual doesn't say anything about so I wanted to ask the infomative members here...I was wondering when the Denso Iridium IK20 are supposed to get changed?...and I seen a member gap them to .0039(could of seen it wrong) when the spec shows .0035 is there and advantage to that gapping?
You NEVER want to INCREASE the gap on any forcedinduction motor. ANY form of forcedinduction causes a GREAT increase in cylinder pressure which makes it MUCH harder on the spark to jump the gap. In my stang, stock gap was .050, and recomend gap, with supercharger was .035. Some blower manufactures actually recomend gaps as small as .030, unless you have an aftermarket ignition system, which provides ALOT more energry at the plug to jump the gap.
As far as changing them, unless you drive a gizzioln miles, I know I will not be changing mine during this decade
See yeah
Thread Starter
MBWorld Fanatic!
Joined: Feb 2006
Posts: 6,213
Likes: 8
LET C32 2002
oem gap should be the same as the non amg 320 engine .039
http://www.ngk.com/results_app.asp?AAIA=1416912
we go 100,000 mile,your Quick motor someone with the interval amg will chime in.
enjoy the beast
http://www.ngk.com/results_app.asp?AAIA=1416912
we go 100,000 mile,your Quick motor someone with the interval amg will chime in.
enjoy the beast
Corrected now
Thread Starter
MBWorld Fanatic!
Joined: Feb 2006
Posts: 6,213
Likes: 8
LET C32 2002
Hey used:
You NEVER want to INCREASE the gap on any forcedinduction motor. ANY form of forcedinduction causes a GREAT increase in cylinder pressure which makes it MUCH harder on the spark to jump the gap. In my stang, stock gap was .050, and recomend gap, with supercharger was .035. Some blower manufactures actually recomend gaps as small as .030, unless you have an aftermarket ignition system, which provides ALOT more energry at the plug to jump the gap.
As far as changing them, unless you drive a gizzioln miles, I know I will not be changing mine during this decade
See yeah
You NEVER want to INCREASE the gap on any forcedinduction motor. ANY form of forcedinduction causes a GREAT increase in cylinder pressure which makes it MUCH harder on the spark to jump the gap. In my stang, stock gap was .050, and recomend gap, with supercharger was .035. Some blower manufactures actually recomend gaps as small as .030, unless you have an aftermarket ignition system, which provides ALOT more energry at the plug to jump the gap.
As far as changing them, unless you drive a gizzioln miles, I know I will not be changing mine during this decade
See yeah
MBWorld Fanatic!
Joined: Jan 2007
Posts: 3,342
Likes: 11
From: PA
S600, GL450, GLC 43
A tighter gap has many gains on ALL forcedinduction cars, I could write a thesis on it here, but would suggest to look on line for all the engineering details, or PM me
Yeah, dropping it a little has a good effect on both the ignition system, and lessens the chance of a blow out, spark that is. Since our little sixs use two plugs per cylinder, I can't posibly see ANY draw backs on narrowing up the gap a little, and only see potential gains. One of the reasons for a BIG gap is to allow for a better flame propagation. Since we already have two, I can't imagine how tighting them up alittle, .0004, could hurt this. Plus as I mentioned it will have the added effect of putting less strain on the coil backs, ie less amperage through the coils because of reduced energry needed to jump a smaller gap.
Oh well, have to run used see yeah
Thread Starter
MBWorld Fanatic!
Joined: Feb 2006
Posts: 6,213
Likes: 8
LET C32 2002
Hey used:
A tighter gap has many gains on ALL forcedinduction cars, I could write a thesis on it here, but would suggest to look on line for all the engineering details, or PM me
Yeah, dropping it a little has a good effect on both the ignition system, and lessens the chance of a blow out, spark that is. Since our little sixs use two plugs per cylinder, I can't posibly see ANY draw backs on narrowing up the gap a little, and only see potential gains. One of the reasons for a BIG gap is to allow for a better flame propagation. Since we already have two, I can't imagine how tighting them up alittle, .0004, could hurt this. Plus as I mentioned it will have the added effect of putting less strain on the coil backs, ie less amperage through the coils because of reduced energry needed to jump a smaller gap.
Oh well, have to run used see yeah
A tighter gap has many gains on ALL forcedinduction cars, I could write a thesis on it here, but would suggest to look on line for all the engineering details, or PM me
Yeah, dropping it a little has a good effect on both the ignition system, and lessens the chance of a blow out, spark that is. Since our little sixs use two plugs per cylinder, I can't posibly see ANY draw backs on narrowing up the gap a little, and only see potential gains. One of the reasons for a BIG gap is to allow for a better flame propagation. Since we already have two, I can't imagine how tighting them up alittle, .0004, could hurt this. Plus as I mentioned it will have the added effect of putting less strain on the coil backs, ie less amperage through the coils because of reduced energry needed to jump a smaller gap.
Oh well, have to run used see yeah
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Senior Member
Joined: Oct 2006
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From: Miami, FL
02 C32 AMG sold!
Hey used:
You NEVER want to INCREASE the gap on any forcedinduction motor. ANY form of forcedinduction causes a GREAT increase in cylinder pressure which makes it MUCH harder on the spark to jump the gap. In my stang, stock gap was .050, and recomend gap, with supercharger was .035. Some blower manufactures actually recomend gaps as small as .030, unless you have an aftermarket ignition system, which provides ALOT more energry at the plug to jump the gap.
As far as changing them, unless you drive a gizzioln miles, I know I will not be changing mine during this decade
See yeah
You NEVER want to INCREASE the gap on any forcedinduction motor. ANY form of forcedinduction causes a GREAT increase in cylinder pressure which makes it MUCH harder on the spark to jump the gap. In my stang, stock gap was .050, and recomend gap, with supercharger was .035. Some blower manufactures actually recomend gaps as small as .030, unless you have an aftermarket ignition system, which provides ALOT more energry at the plug to jump the gap.
As far as changing them, unless you drive a gizzioln miles, I know I will not be changing mine during this decade
See yeah
the sparks, which means the ignition system is inefficient. I remember on
my M3 turbo at 19psi I would run .0027 gap with a MSD ignition, and on
my IS300 Turbo at 17psi I would run .0029 gap with a MSD ignition.
The bigger the spark (gap) the more power it would make. Unless the C32
is hitting over 25psi, I wouldn't go that MUCH lower than the stock gap
(.0039). And after consulting with a few friends who runs high boost (30+
psi Supras) they told me to try .0035 gap. In a 2-3 more months I'll check
my gap, at six months I'll see how much the grap grew, and that'll tell me
if I need to go higher or lower than .0035 gap that I began with.
