Big CFM 914 Heads In U.S.A.

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Re: Big CFM 914 Heads In U.S.A.

Post by raygreenwood » Sun Jul 16, 2017 1:09 pm

Piledriver wrote:
Tue Jul 11, 2017 1:40 am
OK, Nippondenso actually makes iridium electrode, triple ground plugs, ALSO with platinum tips on the 3 ground straps, for $15... 2 side electrodes and one over the top (std location)
Just need to figure out 'densos completely different part# system...

Almost, the lexus plug is 26mm reach, they use the same code for multiple things grrr...
Thanks for the search efforts Pile!

Yes....the NGK identically well as far as running. I have never been able to find a tuning difference...meaning its a direct swap.

However...there is "some" difference. In my experience the NGK BP6ET plug always comes out in the 30k miles range "looking" different than the Bosch W7DTC. It appears to plate a uniform coating of fine tan carbon onto everything....while the W7DTC appears to plate that to the ceramic, the center electrode...and a black or dark gray, uniform carbon coat on the side electrode ring...but the side electrodes themselves seem to remain fairly "bright".
Whether this is a slight variation in plug temperature.....or a quality of the plating itself....I do not know.

One thing I will that the nickel plating of the older style Bosch super in my opinion....superior in polish and adhesion. The surface polish of the NGK plugs nickle plating is slightly less lustrous. Whether this is because the Bosch plugs go through a polish step or the NGK plug does not...or if its from an alloy in the nickel...I do not know.

Not saying this makes one better and the other less than....its just that they are a bit different in "some" respect.

Back in 2009 I used a set of Bosch F7DTC plugs in my 2006 Jetta in the five cylinder engine. They worked very well....but were not resistor and caused a strange trouble code..... so I installed a set of FR7DTC. They are both a 16mm hex.

If these are still around they would also be viable. Ray

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Re: Big CFM 914 Heads In U.S.A.

Post by trapnm » Mon Jul 17, 2017 11:08 pm

Ray, good to have in the back of my mind since I'll be running efi.

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