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What type of spark plug do you use?


1JZGTE

What type of spark plug do you use in your Supra?  

38 members have voted

  1. 1. What type of spark plug do you use in your Supra?



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my trd grade 8ts killed my last engine?????

 

I dunno, you tell us! :D

 

My preference is coppers but like the NGK Iridiums too from a fit and forget for a while longer perspective without having to gap them.

 

Wouldn't touch the Denso iridiums with a bargepole - have seen them fail and kill engines too many times in person and heard about many more failures. Might as well be called Denso Glassiums.

 

I hear the fastest BPU car in the club runs coppers.... maybe they give an extra 20bhp?!? :eyebrows:

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Iridiums are a waste of money, to date I have never heard a good reason for fitting them. They last only fractionally longer than NGK coppers, but cost 4-5 times as much. There's no performance benefit either.

 

Can anyone explain in technical terms why iridiums are worthwhile? They appear to have more negatives than positives in terms of performance and "should the worse happen"

 

Have a chat with Ryan tomorrow about what we found with my car, with the R7436-9 NGK's it performed great, we tried putting a couple of sets of coppers in it when mapping but they never lasted 2 mins on boost (1.6bar) and where there was no knock on my R7436-9 NGK's with the coppers he could here knock straight away.

 

The R7436-9 NGK's are expensive but ive mapped with them and done many miles on both my supras and they have been faultless.

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Have a chat with Ryan tomorrow about what we found with my car, with the R7436-9 NGK's it performed great, we tried putting a couple of sets of coppers in it when mapping but they never lasted 2 mins on boost (1.6bar) and where there was no knock on my R7436-9 NGK's with the coppers he could here knock straight away.

 

The R7436-9 NGK's are expensive but ive mapped with them and done many miles on both my supras and they have been faultless.

 

What's different with those design wise Jamie? Might be tempted to try a set...

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Have a chat with Ryan tomorrow about what we found with my car, with the R7436-9 NGK's it performed great, we tried putting a couple of sets of coppers in it when mapping but they never lasted 2 mins on boost (1.6bar) and where there was no knock on my R7436-9 NGK's with the coppers he could here knock straight away.

 

The R7436-9 NGK's are expensive but ive mapped with them and done many miles on both my supras and they have been faultless.

 

I will talk to Ryan tomorrow, always interested to learn more.

 

However, I would expect this to be more boost related so only applys to cars running high boost on larger turbo's. 1.6 bar is a lot of boost to run, so of course that's pushing the limits of what is useable on 'normal' cars.

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I will talk to Ryan tomorrow, always interested to learn more.

 

However, I would expect this to be more boost related so only applys to cars running high boost on larger turbo's. 1.6 bar is a lot of boost to run, so of course that's pushing the limits of what is useable on 'normal' cars.

 

Would have to agree - I'm guessing the coppers were BKR7E's so heat range 7. The Iridium model code mentioned by Jamie looks to indicate heat range 9 so is a plug 2x heat grades colder designed to work at much higher cylinder temperatures.

 

Detonation would occur in such a scenario with too hot a plug for the application because the plug effectively ignites the mix in the cylinder before the ECU fires it because it's so hot, so at the wrong time in the combustion cycle.

 

Gapping also becomes increasingly important in higher pressure (boost) cylinder conditions as the spark ends up getting blown out whilst trying to jump from the central to the ground electrode. A smaller gap makes that jump easier but the trade off is a resultant increasingly smaller flame front which can mean a less effective explosion.

 

Cheers,

 

Brian.

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