I've been trying to search the forum for the correct part numbers but I am at a loss and the answers were very vague. Not to mention I know they made a change some time ago to a new type of plug. I kept reading about a hot plug and a cold but I am not sure which one I should be using.

Anyways, I am getting ready to change out my coils and plugs but I need the part numbers for the plugs. Can someone help me please. A link would be nice too.

 

They are also listed in the vendor area.

http://www.finishlineperformance.com...n&key=RX8M1004

 

Are those the same as the ones sparkplug.com has for $80 for a set of four?

Ken

 

http://www.sparkplugs.com/results_ap...1&AAIA=1416844
I got mine there, NGKs are the OEM plugs. Cheaper than Mazda dealerships when I checked.

 

You can get the 7 heat range leading plug anywhere.

but to get the 6 plugs, you have to get it from Mazda dealers.

 

I just changed mine with the NGKs from sparkplugs.com about 2 weeks ago. So far, so good. Idle seems a lot smoother.

 

I purchased my new plugs (NGK) from MazSport's EBay store for $7.59/each.
You'll need to buy 2 leading and 2 trailing plugs (or 4 trailing if you're running turbo).
I installed them a couple months ago and they work fine.

 

dont have to go to dealer for a heat range 6 plug
they might not have it in stock, but you can have whatever your local parts place is order you whatever you want.

 

If you are talking about RX-7 plugs (BUR9EQP [NGK-5255], IRE01-31 [NGK-5720]), DO NOT run those in your trailing position. They will bottom out and distort your housings.
If you are talking about OEM RX-8 plugs (RE7CL, RE9BT), do not run trailing plugs in your leading position. They are too short and the electrode design will induce shrapnel.

Either run correct OEM plugs in their proper positions or run RX-7 trailing plugs (BUR9EQP [NGK-5255])in the leading position for turbo applications if so desired.

 

yep --good and spot on advice. What I wonder about is why the hell these plugs cost $20 bucks apiece--nothing special about them. freaking rip off.
olddragger

 

maybe just me I just cant find the OEM heat range 6 plug anywhere, this part number does not even exist in their database.

 

Interesting to hear MazdaManiac... I was only going by what MazSport says on their site. I even emailed them to verify because I want to purchase a turbo next spring. I am curious as to why running these trailing plugs in the leading position will induce shrapnel. Thanks again for the correction and I'm glad you informed us (me) of this.

My trailing plugs are the BUR9EQP (NGK-5255) and my leading plugs are the BUR7EQP (NGK-4764)

 

Mazda part number: N3Y9-18-110

 

huh, thats odd
i work at a shop and we have advance order stuff all the time that they dont have in stock, especially speciality spark plugs.

maybe their all anti-rotary as well, haha

 

AH... good question! I too am anxious to hear!

 

Colder plugs can help resist pre-ignition.
In general, you want to run the coldest plug you can that wont foul.
You wont make more power, though.
On a rotary motor, because of the plug design and location, it is less likely to be a source of pre-ignition.

 

on piston engines, you wanna go colder in the heat range when increasing compression ratio or FI'ing a car. No, heat ranges WILL NOT give you more horsepower. Heat ranges of plugs affects how much heat the plug pulls out of the combustion chamber.
I think its not until your increasing comp ratios upwards of 2 to 3 points and adding like 10+ lbs of bo0st that you need to worry about the heat range of a plug.

although, this is all info for piston engines, not really sure if its the same on the rotaries, it might be

 

^^ Though that "rule of thumb" might be usable, there is no science in it.
We call that "Duketology", Like "Dukes of Hazzard".

You need to know the saturated temperature inside the combustion chamber to make any assumptions about what heat range is equal to what change in effective VE and Pr.

 

actually, there is science in it, of sort
over the years, people have found that when doing certain things to engines, such as teh tings I mentioned ... you need a colder range plug. Or, if you do other things, you need a hotter plug.
to be sure if you have the proper range plug, some visual inspection as well as numerical data about your engine, combustion chamber, compression ratio and other factors are needed.

since they dont make 1/2 ranges, theres not much to choose from. But like was stated above, you want the coldest range plug you can run without it fouling.

 

communicating with brisk to try and find out if they are going to do a rotary plug
olddraggersee

 

I was talking about shops other than Mazda dealers. They cant get it. Only Mazda dealers can get them.

:P

Thx for the part number tho, so I dont have to dig thru the engine no start tsb.

 

Has anyone seen any damage from running 3rd gen plugs in the T?? I just put them in, went in smooth and the car runs great. I run them in my 1st gen too without issue.

I did notice a thread length difference, but the total length of the plugs is almost the same when you take in the hight of the little electrode the 8's plugs have.

 

The trailing plug on the FD is 21mm. The trailing on the RX-8 is 19.
When you tighten an FD trailing plug into the Renesis trailing plug hole, it bottoms out before the gasket hits the mating surface.
This means the base of the electrode is pushing against the housing.
I've seen the damage. Don't do it.

 

hmm, because I have them in now and it runs fine, MPG is back up and like I said they went in smooth and tightened up, I didn't torque them very hard either when they stopped I pushed a little and let it be. I may pull the T out and check for rub marks.

 

Iridium