Spark plugs

[rayjay]

I know use the search... Help a old timer out. Its been years since my last plug change. What is everybody recommending these days for NA engine with bolt ons and tune?

[Blackmobile]

NGK TR6 is what I've used!

[martyo]

NGK TR6 is what I've used!

Part number 4177.

[RF Overlord]

^^^what they said^^^

or Motorcraft SP-413

[fastblackmerc]

NGK's FTW......

[fordfrk]

I installed NGK TR55GP Platinum plug in Hammerdown's car

[rayjay]

Thanks folks. NGK it is. :burnout:

[MOTOWN]

Hard to beat NGK TR6 plugs , thats what i run as well.

[Logizyme]

TR6 on an NA?

Wouldn't you want to at least set gap a bit higher?

I would think one step colder motorcrafts for a bolt on car.

[MOTOWN]

TR6 on an NA?

Wouldn't you want to at least set gap a bit higher?

I would think one step colder motorcrafts for a bolt on car.

TR6 plugs are one step colder.

[Logizyme]

Yeah but their starting gap is .038, which is great for a boosted application but more can be had with a larger gap closer to the stock .054, which would be pushing the limits of adjustment with the TR6.

IDK, its a spark plug, for your application its really whatever, anything you choose will do the job - just wondering.

[MOTOWN]

Yeah but their starting gap is .038, which is great for a boosted application but more can be had with a larger gap closer to the stock .054, which would be pushing the limits of adjustment with the TR6.

IDK, its a spark plug, for your application its really whatever, anything you choose will do the job - just wondering.

Your right you clearly don't know , a TR6 can be gapped where ever you need it to be gapped at.:shake:

[fastblackmerc]

Yeah but their starting gap is .038, which is great for a boosted application but more can be had with a larger gap closer to the stock .054, which would be pushing the limits of adjustment with the TR6.

IDK, its a spark plug, for your application its really whatever, anything you choose will do the job - just wondering.

What??????????????????

[babbage]

Yeah but their starting gap is .038, which is great for a boosted application but more can be had with a larger gap closer to the stock .054, which would be pushing the limits of adjustment with the TR6.

IDK, its a spark plug, for your application its really whatever, anything you choose will do the job - just wondering.

Actually Logizyme is correct. According to NTK:

Proper Gapping Instructions
September 30, 2012

If it is necessary to widen the gap, do so with a tool that only pulls back on the ground electrode without touching the Center Electrode (http://www.ngk.com/learning-center/article/185/proper-gapping-instructions#165) or the porcelain. To close the gap on a plug, gently tap the plug, electrode first on a hard surface.
NGK doesn't recommend adjusting the plug gap more than .008" in either direction. Beyond that slight adjustment, the ground electrode and Center Electrode (http://www.ngk.com/learning-center/article/185/proper-gapping-instructions#165) won't align properly, hindering spark plug performance and drastically reducing plug life.


Due to the fragile nature of their electrodes, special care should be taken when adjusting the gap on Fine Wire (http://www.ngk.com/learning-center/article/185/proper-gapping-instructions#67) plugs.



Gapping should never be attempted on Multi-Ground (http://www.ngk.com/learning-center/article/185/proper-gapping-instructions#290) plugs.

http://www.sparkplugs.com/Data/uploads/Adjust_Electrode_Gap.jpg


http://www.ngk.com/learning-center/article/185/proper-gapping-instructions

NGK 4177 TR6 V-Power Plug = 0.040 gap + .008 = .048

0.048 - 0.054 = .006 over max adjustment according to NTK/NGK.

Sure the angle is small, but technically he is correct.

[justbob]

I just pulled my TR6 plugs after running them two years/10,000 miles with boost in the upper teens. They were gapped at .25 and look so good they might just go right back in.


Builder Of Badassery

[rayjay]

Ok, do I gap them or leave them as they come out of the box? :confused:

[RF Overlord]

You should always check the gap out of the box and adjust it as necessary. Contrary to popular opinion, spark plugs are NOT "pre-gapped"...

[cer0413]

Ok, do I gap them or leave them as they come out of the box? :confused:
non boosted or n/a motor is .054

[fastblackmerc]

You should always check the gap out of the box and adjust it as necessary. Contrary to popular opinion, spark plugs are NOT "pre-gapped"...

I gap plugs at the lowest spec. As the plug wears it will still be in spec. For instance if the gap is .052 to .056, I gap the plugs at .052.

[rayjay]

Ok. Just wondering because of what was stated above about changing the gap more than .008 on NGK plugs. I've always gap'd to engine spec in the past. IIRC I have OEM plugs in there now. Probably in the neighborhood of 50K on them. Car runs fine, its just time to change them out. Also time for the yearly oil change. Royal Purple, 5W-30 with MotorCraft filter. I don't put a lot of miles on the car anymore. Under 4K this past year and thats with a trip back to upstate NY.


Rex Weinbender 11-14-13 :alone: copied this from RF. Miss Rex, main reason I have stayed away. Just not the same with out him. RIP buddy.

[Logizyme]

I believe that plugs are pre-gapped, thats not to say the gap didnt change during shipment, so its not a bad idea to check gap when un-boxing your new spark plugs. Most spark plug manufactures will specify NOT to adjust spark plugs at all - but of coarse we know that you can adjust gap on most spark plugs with proper care and tools. Regardless of if a spark plug can be gapped or not, excessive adjustment to the gap can and will mess with performance and a spark plug of correct or closer starting gap should be considered.

Regarding performance of an NA Marauder, there is the potential for loss of performance with a gap of .038/.040 as the TR6s start off at, and I would suggest staying closer to the factory spec .054. The TR6 gap is ideal for boosted applications where the .054 gap would deminish performance.

But agian, ITS A SPARK PLUG, its going to spark, GET SOME NEW ONES, put them in, THEY WILL WORK. I'm not really trying to start an arguement here, if you think you can change gap on a plug +/- .020 then fine, if you think .040 is a good gap for an NA Marauder fine, I'm just stating what I think.

[RF Overlord]

Not to start an argument, but spark plugs are used in many different applications and there's no way for the manufacturer to know what application you have, so I don't know how spark plugs can be "pre-gapped".

For the record, I installed NGK TR6s (4177) in Mary's car a few years ago at Marty's suggestion, and I gapped them to .054 and her car runs fine. If there was going to be a problem, I would assume it would have shown up during her laps at Atlanta Motor Speedway during MV11. I don't recall if they had a much narrower gap out of the box.

[Logizyme]

Pre-gapped as in if you go into any FLAPS and ask for spark plugs for a MM you will only be given options of spark plugs that start at the 0.056 gap.

TR6 are not specified for the Marauder, but they have the same seal design, threads, and basic design allowing them to fit into our heads the same as a factory plug - the TR6 may be pre-gapped to the spec of another vehicle or they may be considered universal or a custom performance part and not have any vehicle they are spec'd too.

Spark plug manufactures likely have the exact same plug with multiple gaps and multiple part numbers for those gaps. Spark plugs do not have many variables. Certainly there are odd-balls for each of these but for 95% of cars there are: 2 different seal designs, 2 different threads, then whatever manufacturer and model of the spark plug, and a largely varying gap.

Also while your down at FLAPS look at the packaging for each of the spark plugs they offer for the MM. You will find that +75% say "Pre-gapped do not adjust" so if you find that your spark plug is out of specification out of the box it should be returned as defective and not adjusted(although you certainly could adjust it).

[RF Overlord]

What you say makes sense...thanks.

[BLACKMARAUDER04]

I use Motorcraft copper plugs w/ in a colder range for my Marauder
with a tune. I go with SP505. Very inexpensive from Rockauto.
They are gapped to Mercury Marauder's Standard gap.

[Cobra25]

All I ever use in my Marauder is NGK TR6 plugs. Never a problem.

[Dobs]

I use Motorcraft copper plugs w/ in a colder range for my Marauder
with a tune. I go with SP505. Very inexpensive from Rockauto.
They are gapped to Mercury Marauder's Standard gap.

Sound good

[fastblackmerc]

All I ever use in my Marauder is NGK TR6 plugs. Never a problem.


I use Motorcraft copper plugs w/ in a colder range for my Marauder
with a tune. I go with SP505. Very inexpensive from Rockauto.
They are gapped to Mercury Marauder's Standard gap.

I normally use the TR6's, but I got a set of SP505's for free so they are in the MM now.