Hey there, this is Keith from Canada!
I am trying to find out what the best Spark Plug is for my 1994 3000GT VR4. Mitsubishi calls up Part# MS851336 but they can’t get them for 3 - 4 weeks and they want $30 each.
Does anyone have an alternate that they would recommend?
Also, what is the Gap as I read through a blog and there seems to be several opinions that it should be anywhere from .032 to .044.
Any help would be appreciated.
Keith
Ordering through Mitsubishi is probably the most expensive option. The OEM spark plugs specified in the service manual (NGK PFRGJ-11) are no longer available. NGK specifies IFR6E-11 (part number 6741) as the equivalent replacement (which is actually a better spark plug than the original).
I found a set of 6 of these spark plugs on eBay for under $70 USD.
The only thing to watch for when buying on ebay (or Amazon) is getting counterfeit parts. They may be marked and packed as NGK, but they may be some no name junk.
Now I’m concerned. I watched some videos comparing legit vs counterfeit spark plugs, and the results are mixed for me 9some details match the legit parts for me, while some other details match the counterfeits). Maybe the counterfeits have gotten better since those videos were made.
I’m contacting NGK to see if they can help confirm whether some of these details are correct, or a sign of counterfeits.
I was lucky enough to find the NGK plugs PFRG-11’s but not sure if they are actually fake or real, they look like normal plugs with all the markings, who cares as long as they work right? China has excelled in making quality items one should know that fake or real. So fake or real, I simply bought a spark plug tester and they all worked fine. May be using fake plugs may add 100hps to your GTO!! 
Hey there: I found some more information on the Spark Plugs for my VR4.
I have attached a picture showing the Mitsubishi Spark Plug called for (MS851336) and the box which clearly shows it is also an NGK PFR6J-11.
I also have attached the NGK Upgrade Chart and on Page 4 it shows the cross references for PFR6J-11 with the OEM Part# 2743 and the NGK Iridium Upgrade as IFR6J11.
I am going to go with the Iridium version as I have heard it is the best hope.
I hope this helps everyone.
Keith
MS851336 Genuine Mitsubishi SPARK PLUG (NGK PFR6J-11).pdf (181.8 KB)
NGK Upgrade Chart.pdf (262.7 KB)
Hey there.
I posted some information on the VR4 Spark Plugs on another post.
Let me know if you can access it as I am note sure everyone can.
Keith
Both files opened up just fine in PDF format.
Man… why does this have to get so confusing? I referenced NGK’s product page for the PFR6J-11, which claims that the IFR6E-11 is the replacement: https://www.ngk.com/ngk-2743-pfr6j-11-laser-platinum-spark-plug
I can’t find the difference between IFR6E-11 and IFR6J-11. The product comparison tool on NGK’s website shows no difference between them for any of the specifications.
I found a part number decoding chart, and all it says about that letter in the part number is that it is a “special code” for the “firing end construction”.
I hope the difference isn’t important, because I’m past the return window for my order.
Update on my counterfeit concerns…
NGK verified that my spark plugs are legit. So some of the details that people point out as signs of fakes are not necessarily signs of fakes:
Another helpful response from NGK:
There are no differences between IFR6E11 versus IFR6J11. They are identical plugs. IFR6E11 are more commonly used part number. IFR6J11 is only used by Suzuki.
I have checked the book gap should be 0.039 to 0.043 in. ( i have full workshop book if you need it send me your email i will send over for u.
FYI: The service manual and many other technical documents are available for free download here: Tech - Manuals! Service, Technical , Reference | 3SX Performance Home Page
