I had to change the plugs in my 91 earlier this week and noticed they only had 12k miles on them. I got to run plugs a lot longer in my 1st gen.

 

Anything over 10k is gravy...
Power can start to decay as early as 5k miles.


-Ted

 

The length you can use plugs depends on the plug type, how clean the oil and fuel are, and how clean the air going into the motor is.

I normally recommend a 10K mile replacement for performance applications without a CDI ignition system, but you can typically use spark plugs for up to 30K miles if performance and mileage are not big concerns.

 

I think the FC leadings fire twice than the SA ones?


-Ted

 

what plugs do you guys recommend?

 

Stock NGKs.
BUR7EQ leading
BUR9EQ trailing

Can be had for not much from most general autoparts stores (Kragen here sells them for $5 a piece I believe).

 

Can premixing lead to plugs fouling quicker?
Is it viable to clean the plugs with say a metal brush every now and again if there is still plenty of electrode?

 

love the ff black mage avatar mhopkins (sorry to be way the f off subject)

 

Just changed the plugs in mine. Must have been like 15k miles since the last change. You know, AdvanceAutoParts can get you platinum tipped plugs for like 8 bux each. Not bad.

OMG I'll kill someone who did it the last time on my engine: The rear leading plug had a bad connection and was barely sparking! It was soooooo black. My car was mostly on the trailing plug on the rear rotor.

 

I just got them from advance and the plats were just under 7 bucks a piece. They are only a buck more a piece so you should just use them.

 

Any advantage?

 

wow.. I pay $27 canadian for stock ngk's

 

Thats like $6 US right? Yeah that sounds about right.. hehe just jokin

 

I ran my plugs briefly under a wire wheel to clean them. The plugs that cam in my car had the center electrode worn down to a dome (Ant hill) shape instead of the cylindrical shape of new plugs. This is the plug inspection process I am going to use on this car. I usually check for an in increase in gap on plain old plugs.

O'reily's has the plugs for $5.50 so that will save you $2 over the set .

Do not go to Autozone becasue the only plugs they had where $35 each for iridium! They have the NGK's online for $18 each.

RX-7 World has hot and cold plugs listed. http://rx7world.com.phtemp.com/catal...0_products.htm

Has anyone tried the hot plug and seen a change?

 

I've just changed last week my "cold" (7,9) plugs for hotters (6,8), Mazdatrix explain the difference, They run, for the moment, very good actually.

http://www.mazdatrix.com/ign-2.htm

 

In general platinum plugs are supposed to last longer than standard copper ones. That is the only benefit.

 

They last longer than regular ones. Here is something from Car Talk: http://www.cartalk.com/content/colum...bruary/10.html. The mileage is obviously going to be considerably lower for a rotary, though.

 

I just checked mine must be roughly 3k or so and they seemed fine.. however I did notice the leading plug on the rear rotor looked like it was burned in a bit on the fingers.. almost alike a spall circle ingraved around the center edge of each prong... is that normal?