hey everyone, I am changing the spark plugs in my 8, I heard that brown is okay, and that black is bad, so what if you get both, here is a quick picture


is back rotor


is front rotor

does that look good?

seems to have some kind of carbon build up too

I recently got the car, and from what I gathered these plugs where installed sometime in 06

I noticed however that the trailing plug on the front rotor was black, and the ignition wire was loose. There seemed to be some kind of rusted metal on the inside of the plug wire itself, I cleaned it out best I could, and crimped the metal a little tighter so it would hold on to the plug.

the end of the plug that connects to the ignition wire, was a little green too....

none of the parts stores have ignition wires either....

 

looking at getting some new wires, anyone try magnecor?

 

Magnecor is a good brand. Get some OEM plugs as well.

http://www.good-win-racing.com/Mazda...14R-1003B.html
http://www.fluidmotorsports.com/p-95...ccesories.aspx

In most cars a grey ash is the norm, but since the rotary burns some oil as a result of apex seal lubrication ours tend to be more brownish.

 

They don't look horrible (I have seen worse), but they look due for replacement.

 

they're not terrible but I'd definitely replace them with another set of OEM plugs. (OEM plugs seem to perform the best on our cars)

send a PM to this forum Vendor, he's got some good prices on OEM plugs and some upgraded MSD wires.
Charles R Hill - aka BHR

 

I have tested both the Magnacore wires and the MSD wires.

The Magnacore's emit more EMI noise than the MSD's. More EMI noise will induce cross talk which will cause more misfires.

 

Look about normal to me.....

 

thanks all for your input!!!

The car feels a lot better with the new plugs and the one connector criped!!

I ordered some magnacors before you posted 09factor, I will keep this in mind....

 

Those look fine.

For the record.

Brown-ish is good

Black is too rich.

White is too lean.

You replaced it already so

Yeah get some new wires

 

Oh come on now. High quality cables, such as Magnacore, MSD, et al, have very good insulation that precludes crossfire (btw: I can say Crossfire in this context since it's a bad thing

Methinks we sometimes (always?) over analyze things 'round here - I'm as guilty as any at times. You'll be just fine with Magnacore.

 

I've always preferred MSD ... probably because there has never been a problem with them... how can u argue that! haha

 

The revealing part of "reading the plug" is basically the center insulator. We don't get a real good look here, but from what I can see they look pretty clean. If anything they look fairly light and I'd say you were running lean, or maybe just a lot of high-rpms. But that could just be the white-balance of the camera. That's my guess because even the ash deposits on the metal face appear white, which is probably not the case.

Most people want to look at the face of the metal body, which is not that important and especially in the RX-8 tends to look pretty gross due to oil consumption.

 

Just an FYI for everyone - you can get a set of 4 plugs (2 trailing, 2 leading obviously) from Amazon for $66 (shipping is free) which is cheaper than any options I know of.

 

^thats what I did!!

 

^also heard this!

 

Rather than start a new thread I thought I would ask the same question here.

Any thoughts on these?

 

I wish my plugs burned that clean. No deposits at all. Just a tiny, tiny bit rich. Did I say tiny? Rev it up.

 

Woot! Woot! They are only 5,000k old mind you. I have to say, I expected them to say I am running very lean!

Cheers

Andrew

 

Those plugs look great!

 

so u say Black=TOO rich.... Mine are Black black.. and Kinda greasy Looking.....

So If that means its Too rich? is there an Issue? could something be causing the Richness/perhaps affecting my engine in the long run?

 

is it an issue or not ---- gotta read ur computer's fuel trim to know (to be more specific its the enrichment, like how many %)

could something be causing it? I would say of course --- I mean if ur car is running 100% correctly, it shouldn't happen right ?

but it could be a lot of factors, it could be dirty/crappy gas (its the major cause, actually), it could be weak coils, bad wires, the plug's gap wasn't correct in the first place, wiring issue, hardware ... etc etc. just lots of possibilities

Running too rich will rob ur power for sure. but stock fuel trim always run rich to make sure the CAT stays alive longer.

it could be as simple as "you're not driving it hard enough = your right foot is not *heavy* enough"

my plugs almost always have a bit tan + a bit black, its pretty good for a premixer like me. it was stock 7/9 plugs. Now Im using 6 for leading and stock 9 for trailing, changed about 1K miles ago.

 

These were how dirty my spark plugs were when i changed them at 31,000 miles, bearing in mind they should be changed at 24,000 in the UK.
The electrode was covered in brown carbon and the leading plugs terminals were covered in green rust sort of stuff to the point where one of them had snapped off.
After replacing them with brand new NGK spark plugs my RX8 is running allot smoother and idles allot better as well now!

 

WOW... that is WAY too long for these plugs....

/\ IF you can afford to change them at 12,000 Miles MAX, a weak or old spark is another BAD for engine/coil longevity and fuel mileage.

 

Here are the ones in the car when I bought it , no clue when they were last changed. (pic 1)

2nd pic is of one of my trailing plugs after 10k miles. Not sure what the black stuff was, came off rubbing it with my finger.

 

37,500 Miles
Lubricate All locks & hinges
Replace Engine oil , Engine oil filter , Air cleaner element , Spark plugs

This is what I found on the owner manual, and I have always follow it and I have never had any problem with my enginee!

Then yet again it really depends on how you drive your car, my car is a RX8 GT 2004 with only 65,000+ miles on it, so yes I do baby her, and yet again she rewards me with a smile almost every weekend!!!

QUOTE=ASH8;4118328]WOW... that is WAY too long for these plugs....

/\ IF you can afford to change them at 12,000 Miles MAX, a weak or old spark is another BAD for engine/coil longevity and fuel mileage.[/QUOTE]