Denso U Groove Spark Plugs.-

Sea Rider

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Need to install a set of Q20PR-U spark plugs which somebody told me that were factory gapped to 0.8 mm, question : if my motor works with regular spark plugs gapped to 11 mm, should the Denso plugs be re gapped to 11mm to work properly. These plugs have a middle internal groove under the tip which provides a tad larger spark than regular ones.

Assume that if the spark is bit larger there's no need to re gap them to 11 mm, but who knows ? Is there someone who has installed them and knows about if thie re gap is needed ? Thanks in advance.

Happy Boating
 

racerone

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According to your post.--------There is a big difference between 0.8mm and 11 mm.-----Perhaps a typo here.
 

Sea Rider

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According to your post.--------There is a big difference between 0.8mm and 11 mm.-----Perhaps a typo here.

Yep it's 11 or 1.1mm whichever gap you want to use if using the mm setting as specified by most spark plug manufacturers...

Happy Boating
 

jimmbo

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Some kind of Miracle Spark Plug?
Trenchs/Vee/Multiple Electrodes have been marketed for about 100 yrs. If these were Genuinely a Value Added Product, they would have been utilized during assembly at the Factory
 

Sea Rider

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It's a standard spark plug with a middle groove just on the internal side of the electrode, while the exterior remains flat, needs to be regapped to the motor's specs to work as intended. Provides a bit larger middle spark than a conventionak spark plug.

Happy Boating
 

racerone

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The shelves are full of stuff in the automotive isle.-----Mechanic in a can products.----A wee fortune is made when folks are desperate for a magic cure.-------Come to think of it the medical isle is full of remedies too.-----These products sell because folks do not know the basics of how it works.
 

jimmbo

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It's a standard spark plug with a middle groove just on the internal side of the electrode, while the exterior remains flat, needs to be regapped to the motor's specs to work as intended. Provides a bit larger middle spark than a conventionak spark plug.

Happy Boating
.

I have never seen a Larger/Fatter spark on any of the many different designs of Spark Plugs, besides any Successful Spark will ignite a combustible Air-Fuel mix
 

Truckguy701

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Spark plugs make me laugh. If the gap is to big then you may experience some millisecond delays to fire them and will actually mess very slightly to timing. But in a motor the mixture of gasoline atomized and air it is going to fire. You could run them plugs out of the box at 8mm and have no issues. If you do have a problem well you may have a fuel issue or are low on compression. Hate to let this slip but the most expensive spark plug out there doesn’t increase power or fuel mileage sorry. Some may last longer and not foul as easy.
 

racerone

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But 8 mm is like a 5/16" gap on the plug ????----Another typo perhaps.
 

jimmbo

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a plug with an 8 mm/5/16" gap might not fire when installed and subject to the Higher than Atmospheric Pressure in the cylinder
 

Sea Rider

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Well It's not a miracle spark comes after the standard one. Its for a MG3 that came with a set of Torch brand spark plugs probably you guys never heard of this brand, were regapped from 0.8 mm factory delivered to 1.0 mm (040) Works far better that the originall Torch brand, at $10.00 a box of 4 it's darn cheap.


Happy Boating
 
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