Denso Iridium TT, any one tried it?

[PandaBear]

From what I remember the older 0.4mm iridium plugs last about 15-30k miles, but the newer 0.4mm Denso Iridium TT claims 100k miles life vs the 80-100k miles life the 0.7mm Long Life Iridium. They are also cheaper too.

 

[Bottom_Feeder]

An earlier thread...

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3624567/New_Denso_TT_Iridium_spark_plu

 

[KingCake]

The twin tip is for waste spark systems. Fine wire would work better for coil on plug.

 

[surfstar]

Originally Posted By: KingCake
The twin tip is for waste spark systems. Fine wire would work better for coil on plug.

Denso TT isn't the same as what you're thinking of.

 

[6starprez]

I posted in that earlier thread. I installed them Jan 31, 2015 in my Impreza and have over 31K miles on them now. I get good gas mileage as advertised. Trip to Virginia Beach two weeks ago yielded 40+ mpg from my house to NAS Oceana. Note: I forgot to set the cost per gallon so the fuel cost is way off

 

[Kool1]

I have these in my 03 CRV. I can say that the idle is rock solid. Don't know if there is any horsepower or mpg gain but the idle is super smooth with these spark plugs.

 

[PandaBear]

Has any one of you taken it out to check if the gap has grown? In theory the only down side to the 0.4mm electrode is the reduced life compare to larger ones.

 

[KingCake]

Originally Posted By: surfstar
Originally Posted By: KingCake
The twin tip is for waste spark systems. Fine wire would work better for coil on plug.

Denso TT isn't the same as what you're thinking of.


Yes it is. Notice the platinum tip on the electrode? That's to reduce wear on the reverse polarity bank of a waste spark system. For a COP system you do not need that.

 

[Gokhan]

I believe DENSO Iridium TT is the OEM plug on most new Toyotas. I did use it on my 1985 Corolla once but then went back to the cheap OEM U-groove standard plugs just because I wanted to stick with OEM.

Toyota says that the thinner iridium lasts as long as the thicker platinum but provides higher ignition performance in this 2016 Prius whitepaper (new-car features):

Regarding better fuel economy or smoother idle, I don't think the difference is human-measurable or human-audible. The main advantage of iridium/platinum plugs is longer life with very small improvement in ignition performance, the latter of which you can't really feel. Despite the high price, DENSO iridium TT plugs are a good upgrade or replacement if your OEM plugs or platinum or iridium.

 

[6starprez]

Originally Posted By: PandaBear
Has any one of you taken it out to check if the gap has grown? In theory the only down side to the 0.4mm electrode is the reduced life compare to larger ones.


They were fine after 10k miles. I wanted to check them a few weeks ago but other little projects got in the way. I get to it soon though.

 

[surfstar]

Originally Posted By: KingCake
Originally Posted By: surfstar
Originally Posted By: KingCake
The twin tip is for waste spark systems. Fine wire would work better for coil on plug.

Denso TT isn't the same as what you're thinking of.


Yes it is. Notice the platinum tip on the electrode? That's to reduce wear on the reverse polarity bank of a waste spark system. For a COP system you do not need that.


Thought that was twin GROUND electrodes that were recommended for waste spark systems?
http://s263.photobucket.com/user/cherryz32/media/T4R_PLUGS/IMG_0789.jpg.html

 

[kschachn]

Originally Posted By: surfstar
Thought that was twin GROUND electrodes that were recommended for waste spark systems?
http://s263.photobucket.com/user/cherryz32/media/T4R_PLUGS/IMG_0789.jpg.html


It is, they are used on my old 1MZ-FE.

Just another instance of the "wisdom" of that poster.

 

[SHOZ]

They came stock on my Hyundai genesis coupe 2L.