correct spark plug gap
- Thread starter lucerne06
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If their pre gapped then I assume that'd the gapping number?
Wow 16 heatrange is pretty hot but normal for smogged and lugged passsengers cars. I dont have the data but if you go to denso site++ i might think they'd have it, BUT, 1 - 1.1 mm is the normal gap for a japanese car with dual or single ended coil. Nice plug design for resonant shared coil systems - it sparks gnd to centre as easily as center to gnd.
++
http://www.densoaftermarket.com/catalog/catalog.php?part=sprk
++
http://www.densoaftermarket.com/catalog/catalog.php?part=sprk
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Originally Posted By: JAM25
If their pre gapped then I assume that'd the gapping number?
Never put new plugs in without checking and setting the gap.
That same plug part # will fit more than one applicaton and each application may have different gap specs. Usually the plug will be somewhere in the middle, but most of what I see is that the gaps out of the box are too big.
If their pre gapped then I assume that'd the gapping number?
Never put new plugs in without checking and setting the gap.
That same plug part # will fit more than one applicaton and each application may have different gap specs. Usually the plug will be somewhere in the middle, but most of what I see is that the gaps out of the box are too big.
Originally Posted By: lucerne06
I need the correct spark plug gap for two cars, please
1997 geo prizm 1.6l base
2002 chevy prizm 1.8l base
I'm using the DENSO platinum PK16TT plugs - #4503
the plugs are already pre gapped at 0.040
GM service specs gap of .040-.043 for the 2002.
Parts catalog shows .042 for the 1997.
I need the correct spark plug gap for two cars, please
1997 geo prizm 1.6l base
2002 chevy prizm 1.8l base
I'm using the DENSO platinum PK16TT plugs - #4503
the plugs are already pre gapped at 0.040
GM service specs gap of .040-.043 for the 2002.
Parts catalog shows .042 for the 1997.
Thanks GM boy. close enough
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
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I think GMboy has it covered.
One thing's for sure, 0.028" is wrong unless the car is turbo. You're FINE at .040" with healthy wires (+ cap and rotor if it has a dist). Ill poke on the NGK site, but doenst the car have an underhood tuneup tag showing gap and lash and idle speed settings - or where's the owners manual?
An NGK store showed the plugs listed as BKR 5 (or 6) es-11 the -11 is 1.1mm as I said before.
Ive tuned up HUNDREDS of imports over the years professionally.
Leave em at .040" and carry on. I would NOT run a 16 though UId run a colder ( but still HOT) k20pru11 denso equivalent 16 or 5 is smokin hot smog plug ONLY concerned with cold start emissions and low rpm lugging emissions( misfire counts).
Race tune advice #1313b
Dont get grease and dirt or human sweat on the plug porcelin during the install - it will cause flashover and high misfire counts.
One thing's for sure, 0.028" is wrong unless the car is turbo. You're FINE at .040" with healthy wires (+ cap and rotor if it has a dist). Ill poke on the NGK site, but doenst the car have an underhood tuneup tag showing gap and lash and idle speed settings - or where's the owners manual?
An NGK store showed the plugs listed as BKR 5 (or 6) es-11 the -11 is 1.1mm as I said before.
Ive tuned up HUNDREDS of imports over the years professionally.
Leave em at .040" and carry on. I would NOT run a 16 though UId run a colder ( but still HOT) k20pru11 denso equivalent 16 or 5 is smokin hot smog plug ONLY concerned with cold start emissions and low rpm lugging emissions( misfire counts).
Race tune advice #1313b
Dont get grease and dirt or human sweat on the plug porcelin during the install - it will cause flashover and high misfire counts.
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Originally Posted By: ARCOgraphite
I think GMboy has it covered.
One thing's for sure, 0.028" is wrong unless the car is turbo. You're FINE at .040" with healthy wires (+ cap and rotor if it has a dist). Ill poke on the NGK site, but doenst the car have an underhood tuneup tag showing gap and lash and idle speed settings - or where's the owners manual?
An NGK store showed the plugs listed as BKR 5 (or 6) es-11 the -11 is 1.1mm as I said before.
Ive tuned up HUNDREDS of imports over the years professionally.
Leave em at .040" and carry on. I would NOT run a 16 though UId run a colder ( but still HOT) k20pru11 denso equivalent 16 or 5 is smokin hot smog plug ONLY concerned with cold start emissions and low rpm lugging emissions( misfire counts).
Race tune advice #1313b
Dont get grease and dirt or human sweat on the plug porcelin during the install - it will cause flashover and high misfire counts.
Right on again. Great advice and obviously from a lot of experience. I had forgotten about the underhood tune up label....or the owner's manual.
I think GMboy has it covered.
One thing's for sure, 0.028" is wrong unless the car is turbo. You're FINE at .040" with healthy wires (+ cap and rotor if it has a dist). Ill poke on the NGK site, but doenst the car have an underhood tuneup tag showing gap and lash and idle speed settings - or where's the owners manual?
An NGK store showed the plugs listed as BKR 5 (or 6) es-11 the -11 is 1.1mm as I said before.
Ive tuned up HUNDREDS of imports over the years professionally.
Leave em at .040" and carry on. I would NOT run a 16 though UId run a colder ( but still HOT) k20pru11 denso equivalent 16 or 5 is smokin hot smog plug ONLY concerned with cold start emissions and low rpm lugging emissions( misfire counts).
Race tune advice #1313b
Dont get grease and dirt or human sweat on the plug porcelin during the install - it will cause flashover and high misfire counts.
Right on again. Great advice and obviously from a lot of experience. I had forgotten about the underhood tune up label....or the owner's manual.
Originally Posted By: ARCOgraphite
Thanks GM boy. close enough
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
Closer gapping will also put them out of parallel - makes your point null and void..
You get more quench with a smaller gap - you have it backwards.
I always gap my plugs about .005" wider. If you are on top of maintenance, this is great. Better spark for cruising/leaner conditions, and less quench - better in and out flow.
The platinum nibs get rounded anyways - parallel is not a concern.
Thanks GM boy. close enough
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
Closer gapping will also put them out of parallel - makes your point null and void..
You get more quench with a smaller gap - you have it backwards.
I always gap my plugs about .005" wider. If you are on top of maintenance, this is great. Better spark for cruising/leaner conditions, and less quench - better in and out flow.
The platinum nibs get rounded anyways - parallel is not a concern.
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Only slightly off topic.
How easy is it to damage the platinum or iridium surfaces of these plugs with wire gauges? What precautions, if any, should be used?
Thank you.
How easy is it to damage the platinum or iridium surfaces of these plugs with wire gauges? What precautions, if any, should be used?
Thank you.
The tips stay on in very harsh conditions.
They are not fragile.
If you feel any resistance at all, stop and open her up more - this is safe for anybody.
They are not fragile.
If you feel any resistance at all, stop and open her up more - this is safe for anybody.
Originally Posted By: mechtech2
Originally Posted By: ARCOgraphite
Thanks GM boy. close enough
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
Closer gapping will also put them out of parallel - makes your point null and void..
You get more quench with a smaller gap - you have it backwards.
I always gap my plugs about .005" wider. If you are on top of maintenance, this is great. Better spark for cruising/leaner conditions, and less quench - better in and out flow.
The platinum nibs get rounded anyways - parallel is not a concern.
This Denso TT is a special plug with two plat/Ti hard points. It was supposedly "factory gapped" at .040" so wouldnt open it to 0.043" (1.1mm) Opening the gap (heeled back) puts the spark kernel near the GND strap shell tie in which is cold and shrouded. Agreed that there are so many other factors influencing spark, including indexing - which street guys prob shouldnt do. BTW Packard/DELCO made the the best ignition wire when I was building engines.
Originally Posted By: ARCOgraphite
Thanks GM boy. close enough
this is an easy fire electrode and can be gapped a tad tighter if need be.
You want the electrode "points" parallel so DONT open the gap and end up with a quench happy heeled back electrode. Better to be .005" under gapped then have a lifted gnd electrode.
Racer Engine builder rule # 1313.
Closer gapping will also put them out of parallel - makes your point null and void..
You get more quench with a smaller gap - you have it backwards.
I always gap my plugs about .005" wider. If you are on top of maintenance, this is great. Better spark for cruising/leaner conditions, and less quench - better in and out flow.
The platinum nibs get rounded anyways - parallel is not a concern.
This Denso TT is a special plug with two plat/Ti hard points. It was supposedly "factory gapped" at .040" so wouldnt open it to 0.043" (1.1mm) Opening the gap (heeled back) puts the spark kernel near the GND strap shell tie in which is cold and shrouded. Agreed that there are so many other factors influencing spark, including indexing - which street guys prob shouldnt do. BTW Packard/DELCO made the the best ignition wire when I was building engines.
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There is a larger gap/hole for in and out flow with a larger gap.
We can't get around that.
A very good thing until limits of misfire are achieved.
BTW the ground strap is way HOTTER than the air fuel mixture.
I don't know what you mean by cold.
We can't get around that.
A very good thing until limits of misfire are achieved.
BTW the ground strap is way HOTTER than the air fuel mixture.
I don't know what you mean by cold.
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