I know that this question has been probalby hammered down but I can't find a thread on the 2013. The owners manual says 0.033-0.037. I was thinking 0.028. Any recommendations??
NGK TR6 Spark Plugs gap??
- Thread starter edmed2003
- Start date
2013 Shelby with 127mm JLT, Ford Racing Cobra Jet Monoblade Throttle Body and John Lund tune 93 oct. I have taking it to the dyno but guessing around 680 rhwp?
I bought the 680 rwhp power package from Lethal and they came. Shouldn't I change them??
If they came with the kit I won't dispute them. What I'm saying is usually different plugs are used with higher boost applications (pulleys and such. ) I'm not sure why they included plugs with the kit but you might want to ask them if they are truly necessary. The stock plugs are high quality platinum or iridium (can't remember which)
Stock plugs I believe are iridium (just pulled mine out to do a look see yesterday). TR6 plug is just a V-groove regular style plug.
Been checking NGK's site as of right now they don't show a direct replacement plug for the '13 Shelby.
Been checking NGK's site as of right now they don't show a direct replacement plug for the '13 Shelby.
So I guess I should leave the stock plugs, right? I am going to ask the guys at Lethal tomorrow. Anyone has change their plugs on the 13??
Yes keep the stock plugs until you hear different. Keep in mind the 07-12 plugs were designed for 9 psi. Hence the change for fear of spark blowout at higher boost. The plugs in the 13 were designed for 15 psi. Im curious to see what Lethal says on this
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Maybe regap the factory plugs then. When we pulled them out to change mine yesterday, they were gapped between 33 and 37. I was surprised about the difference. I tightened the gap on my NGK's to 32 (ish).
This is the answer I got from Lethal:
Thanks for writing us. In regards to the 680rwhp package you don't necessarily need to install the TR6's we provide in the kit as the stock plugs are adequate for that power level. If you experience any spark blowout then I would suggest installing the TR6's. Gap them at .030-.032. We do however recommend installing the TR6's if you plan on making in the 700-735rwhp range like you do when adding the 10%-15% lower pulley.
I am going to go for the 15% pulley next so I guess I will change them before it gets here.
Thanks for writing us. In regards to the 680rwhp package you don't necessarily need to install the TR6's we provide in the kit as the stock plugs are adequate for that power level. If you experience any spark blowout then I would suggest installing the TR6's. Gap them at .030-.032. We do however recommend installing the TR6's if you plan on making in the 700-735rwhp range like you do when adding the 10%-15% lower pulley.
I am going to go for the 15% pulley next so I guess I will change them before it gets here.
Thanks for clearing that up. Keep in mind That when you do install the TR6's they are a normal copper plug and will have to be changed about every 3k.
Every 3K, really?
.032
That's the norm for guys running copper plugs in these engines. Lots of cylinder pressure with 15 psi.
NEVER heard this before
Check out post #32. From Justin at VMP.
http://www.teamshelby.com/forums/in...-instructions/page__hl__ spark plugs__st__20
"I get terrible plug life from my NGK TR6s, about 3000 miles, and then the car will misfire under heavy load like 4th gear at the track. I make more power than most GT500s, but not that much more.
One of the FRPP engineers I know that works on the CJ is using one step colder platinum motorcraft plugs in the new and old CJ, AGSF-12FM1 plugs gapped at 0.035", I'm going to try those next.
If you are only upping the boost to 12-13psi with an upper pulley, IMO, i would not bother to change the plugs. Spark blowout is not an issue, and the DOHC chamber does not need a really cold plug. The FRPP TVS kit raises boost to 13psi and they don't require changing plugs."
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..sorry to resurrect an old thread...but if the NGK's are so bad, then why are
Revan Racing & Evolution Performance sending NGK's out with their performance packs?
Are most people simply re-gapping the stockers?
Revan Racing & Evolution Performance sending NGK's out with their performance packs?
Are most people simply re-gapping the stockers?
Van@RevanRacing
Active Member
I send NGK TR6 Plugs with every kit and I recommend to every customer to gap them at .030 per Jon Lund.
I've been using NGK TR6's since 2006 without issue. I change them every 3,000 to 5,000 miles.
These are boosted engines and plugs are easy to change and inexpensive.
I've been using NGK TR6's since 2006 without issue. I change them every 3,000 to 5,000 miles.
These are boosted engines and plugs are easy to change and inexpensive.
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