Which NGK plugs?
Race Director
Joined: Feb 2008
Posts: 17,336
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From: Maker of Sharp Objects, AL - Roll Tide
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17
St. Jude Knife Maker
TR55 is irridium and for long life I believe - good for a stock vette
TR6 is a copper electrode good for higher hp cars.
people have claimed to use both with good results in a stock vette. problem is the TR6 will wear out and needs to be changed pretty often. like every 15K I believe.
Mine are due now.
TR6 is a copper electrode good for higher hp cars.
people have claimed to use both with good results in a stock vette. problem is the TR6 will wear out and needs to be changed pretty often. like every 15K I believe.
Mine are due now.
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 1,058
Likes: 91
From: Indiana
TR55 is irridium and for long life I believe - good for a stock vette
TR6 is a copper electrode good for higher hp cars.
people have claimed to use both with good results in a stock vette. problem is the TR6 will wear out and needs to be changed pretty often. like every 15K I believe.
Mine are due now.
TR6 is a copper electrode good for higher hp cars.
people have claimed to use both with good results in a stock vette. problem is the TR6 will wear out and needs to be changed pretty often. like every 15K I believe.
Mine are due now.
Race Director
Joined: Feb 2008
Posts: 17,336
Likes: 8
From: Maker of Sharp Objects, AL - Roll Tide
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17
St. Jude Knife Maker
Just searched and found this.
The TR55 and TR5 are the same; the 55 is gapped at .055, the 5 is gapped at around .038 I believe. The deal is you shouldn't make a 55 go down to .038.
Go with a TR6 for high compression and power.
NGK recommends you step down 1 step colder for every 100 hp you add.
TR55 is between a TR5 and a TR6 in heat range. Think of it as a TR5.5. TR5 would be stock replacement for your application.
NGK makes ACDelco plugs.
A TR55 is a copper style plug. TR55GP's are a platinum plug.
Copper plugs run cooler and reduce spark knock caused by the super hot platinum or iridium wire.
The TR55 and TR5 are the same; the 55 is gapped at .055, the 5 is gapped at around .038 I believe. The deal is you shouldn't make a 55 go down to .038.
Go with a TR6 for high compression and power.
NGK recommends you step down 1 step colder for every 100 hp you add.
TR55 is between a TR5 and a TR6 in heat range. Think of it as a TR5.5. TR5 would be stock replacement for your application.
NGK makes ACDelco plugs.
A TR55 is a copper style plug. TR55GP's are a platinum plug.
Copper plugs run cooler and reduce spark knock caused by the super hot platinum or iridium wire.
Race Director
Joined: Feb 2008
Posts: 17,336
Likes: 8
From: Maker of Sharp Objects, AL - Roll Tide
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17
St. Jude Knife Maker
Just wanted to add - it might not be a bad idea to call NGK and ask them. I'm sure they know their products 
