Looking to get new plugs for my 03 cobra. Want something better with a tuned and upgraded car. Car has around 500 rwhp right now. Let me know what you think.
Best spark plug
- Thread starter Johnferris
- Start date
Tr6
01cobravortech
Banned
TR7IX is unbeatable for any application under 18psi.
Have run it for almost 119k and not in ONE case, has the spark plug gapped opened up even after a year of use or at least 15k.
Have run it for almost 119k and not in ONE case, has the spark plug gapped opened up even after a year of use or at least 15k.
"Search Function" ?? Never heard of em.
Are those the funny looking nine sided super plugs that all the 30 minute advertising car shows want you to buy?
^^^ Lol, TR6IX in mine.
I use TR6's and will change them yearly if I had too.
Tr6 here. I change them every year since they are cheap. I do less than 5k a year.
This. And, iridiums are more prone to damage when gapping if not done properly. Iridium is a very hard material and more brittle. But iridium plugs last much longer. Performance wise, there is no advantage to using iridium. I'm going to say most use the copper TR6 because they are much cheaper than iridium. And changing plugs on a 2003-2004 Cobra is so easy. In the end, it's more a personal choice. Both will work fine.
Currently I have tr6ix in the car. I may try the 7's though. I've had some good luck with some tr6's and some not so much.
01cobravortech
Banned
I've used the TR6ixs before but the problem with those is that the gap does open up pretty wide over time. The copper TR6s of course have that 'stumbling issue' at idle. Its annoying but tolerable.
My problem with the TR6ixs was needing to gap them to about .032 to get them to run right & unfortunately I'm not an iridium gapping guru. Broke too many tips and running the TR7ix with the out of the box gap of .034 - .036 took care of the concern about being able to safely and correctly gap an iridium plug.
I've always been of the opinion that you should always go with the coldest plug possible, that doesn't foul. And in my own practical experience, the TR7ix performs exactly as the TR6ix.
All that aside, I think NGK makes the best quality plug you can get out there.
Btw, you have some real nice looking arms. You're a handsome looking guy.
I've been using TR-6 plugs for 10 years now 
i have mine at .32 also and my car feels way better. i had them at stock gap and i could tell as soon as i fired her up.
Cool, thanks for info, likely gonna give them a try! Thanks for the kind words!
My Terminator loved both plugs, but the TR6s did not idle as good as the TR7IXs
Firm believer lots of variables make certain cars like one over the other
Firm believer lots of variables make certain cars like one over the other
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