spark plugs
Pro
Joined: Apr 2018
Posts: 563
Likes: 201
From: Montgomery City, MO
I don't need to see any of the details you posted to say Denso 4713 / IT16TT twin-tip iridiums. They're expensive, but they'll deliver strong spark far longer than any copper core plug (even the NGK V-Power). They're also hot enough to be self-cleaning. Consider them to be the last spark plug you'll need to install in this particular car.
Pro
Joined: Apr 2018
Posts: 563
Likes: 201
From: Montgomery City, MO
That's more of an anecdotal argument than a scientific argument.
I won't argue that for the cost the NGK V-Power produces a powerful spark. In testing I preferred it to the factory Delco platinum plugs by a large margin. But it's still a copper core plug and will erode in 25-30k miles. I'm not getting any kick-backs from Denso, but their TT plugs produce just as fat a spark as any copper core plug, and will continue to do so for decades.
I won't argue that for the cost the NGK V-Power produces a powerful spark. In testing I preferred it to the factory Delco platinum plugs by a large margin. But it's still a copper core plug and will erode in 25-30k miles. I'm not getting any kick-backs from Denso, but their TT plugs produce just as fat a spark as any copper core plug, and will continue to do so for decades.
Melting Slicks
Joined: May 2013
Posts: 2,934
Likes: 1,369
From: New Jersey
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This is the first I am reading about a TT - TwinTip spark plug, might be a candidate when I do my plugs if they're as good as ya'll are saying..!
Race Director
Joined: Oct 2004
Posts: 12,791
Likes: 4,614
It is my understanding that nearly all, if not all, plugs today have a copper core. The electrode and ground strap can still use a platinum tip/pad. Copper cores are not an NGK exclusive today. Copper cores are so common they're hardly advertised any longer. Again, that is what I've researched. I could be wrong, so FWIW...
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Pro
Joined: Apr 2018
Posts: 563
Likes: 201
From: Montgomery City, MO
The only thing special about them over any other non-exotic plug is they have a v groove in the tip of the electrode that causes the spark to originate from different points of that v edge, slowing erosion.
Don't get me wrong, they're great plugs for the price. You can buy three sets for what one set of tt iridium plugs cost. But iridium plugs will last essentially the life of the engine, which is why OEMs have been using them for over a decade.
Safety Car
Joined: Mar 2017
Posts: 3,749
Likes: 932
From: Orlando Florida
https://www.ngk.com/ngk-3951-tr55-v-power-spark-plug
actual copper electrodes exposed in the combustion chamber wouldn’t last virtually any time.
Race Director
Joined: Oct 2004
Posts: 12,791
Likes: 4,614
I guess I used non-specific terminology. The V-Power plugs have copper electrodes.
The only thing special about them over any other non-exotic plug is they have a v groove in the tip of the electrode that causes the spark to originate from different points of that v edge, slowing erosion.
Don't get me wrong, they're great plugs for the price. You can buy three sets for what one set of tt iridium plugs cost. But iridium plugs will last essentially the life of the engine, which is why OEMs have been using them for over a decade.
The only thing special about them over any other non-exotic plug is they have a v groove in the tip of the electrode that causes the spark to originate from different points of that v edge, slowing erosion.
Don't get me wrong, they're great plugs for the price. You can buy three sets for what one set of tt iridium plugs cost. But iridium plugs will last essentially the life of the engine, which is why OEMs have been using them for over a decade.
Pro
Joined: Apr 2018
Posts: 563
Likes: 201
From: Montgomery City, MO
Whatever the case, when I was testing different plugs for my ignition controller the Denso tt iridiums hands-down produced the best looking spark over platinum and single tip iridium plugs. I think I also tested a Bosch that had a fine wire iridium electrode and a ground strap with a platinum "rib".
The OE Delco platinum plugs IMO just suck. The spark basically goes around the platinum, creating a "bubble" of very weak spark. I've pulled these out of high mileage engines and the electrodes will be eroded down to a point around the platinum "puck".
The OE Delco platinum plugs IMO just suck. The spark basically goes around the platinum, creating a "bubble" of very weak spark. I've pulled these out of high mileage engines and the electrodes will be eroded down to a point around the platinum "puck".
Race Director
Joined: Oct 2004
Posts: 12,791
Likes: 4,614
Whatever the case, when I was testing different plugs for my ignition controller the Denso tt iridiums hands-down produced the best looking spark over platinum and single tip iridium plugs. I think I also tested a Bosch that had a fine wire iridium electrode and a ground strap with a platinum "rib".
The OE Delco platinum plugs IMO just suck. The spark basically goes around the platinum, creating a "bubble" of very weak spark. I've pulled these out of high mileage engines and the electrodes will be eroded down to a point around the platinum "puck".
The OE Delco platinum plugs IMO just suck. The spark basically goes around the platinum, creating a "bubble" of very weak spark. I've pulled these out of high mileage engines and the electrodes will be eroded down to a point around the platinum "puck".
Safety Car
Joined: Oct 2007
Posts: 4,186
Likes: 1,065
From: South Florida
For over two decades in sr20det, rb2xdet(t), 1/2jz-gte, 4g63, 1/2zz, etc... I setup and tuned hundreds of turbocharged daily drivers
Always use the same procedure
https://forum.hptuners.com/showthrea...l=1#post744925
Iridium NGK is the final plug. Do not contact with human skin.
Always use the same procedure
https://forum.hptuners.com/showthrea...l=1#post744925
When the engine is mechanically electrically sound we tune on the first set.
Then we install a second set to verify the condition of the plugs after mileage.
Tuning will mark up the plugs making them impossible to read. Marks are OLD news from OLD tuning sessions we don't care about anymore so we get rid of them using a NEW set of plugs once the engine is fully tuned. Then, we drive the vehicle many miles 2000 to 12,000 miles to make sure they stay looking great. Then, finally, brand new iridium plugs go in once and for all now it can go 100k miles no issues.
DO NOT touch the brand new spark plugs with your human hands. It will leave residues, carbon, salt, debris, which bake on causing marks. Use DISPOSABLE CLEAN NEW gloves for handling spark plugs.
Do NOT use anti seize on the first set of plugs for tuning. Residual oil in the threads will prevent seizure in the short time we use them. On the FINAL set of plugs we can use a tiny bit of anti seize but applied very carefully using gloves WAY away from the ends.
Then we install a second set to verify the condition of the plugs after mileage.
Tuning will mark up the plugs making them impossible to read. Marks are OLD news from OLD tuning sessions we don't care about anymore so we get rid of them using a NEW set of plugs once the engine is fully tuned. Then, we drive the vehicle many miles 2000 to 12,000 miles to make sure they stay looking great. Then, finally, brand new iridium plugs go in once and for all now it can go 100k miles no issues.
DO NOT touch the brand new spark plugs with your human hands. It will leave residues, carbon, salt, debris, which bake on causing marks. Use DISPOSABLE CLEAN NEW gloves for handling spark plugs.
Do NOT use anti seize on the first set of plugs for tuning. Residual oil in the threads will prevent seizure in the short time we use them. On the FINAL set of plugs we can use a tiny bit of anti seize but applied very carefully using gloves WAY away from the ends.