I recently got my RX7 running and I was going to change the plugs. I purchased DENSO W25EDR's from Auto Zone. Auto Zone claims the gap on them should be .055, also the Haynes Manual claims .05. Does anyone know do the plugs even need regapped or can I just put them in. Thanks!!!!! Also, is there a different plug I should look for? I need plugs good for road driving. Nothing fancy, just a nice set of plugs for cruising!!!

 

You should only use the OE NGK BR8EQ14s

These plugs are designed to work with the Rotory engin, and have to be pre-gaped due to the designe.

Follow this link to learn more about how a conventional spark plug can distroy a rotory engin...

http://members.ij.net/mrmazda/btraps.html#PLUGCHOICE

 

Those Denso's are the same as NGK's. They are already gapped right.

 

Are they 4-pronged? I've only used NGKs & they have 4 prongs. I get um from the dealership (20% off) or Napa. My Mazda cert engine builder told me not to use anything else.

 

yes the densos are 4-pronged, just put some in yesterday....autolites blow.

 

Even though pre-gapped, you should still confirm it before using any new spark plug. My .02 worth

 

I agree - sometimes plugs are knocked around in transit and the gap can be altered.

 

The ND's are actually better plugs than NGK in my experience.
With my old carb'd setup and MSD direct fire,I was eating a set of stock NGKs every oil change.Wasted center electrodes and massive ceramic erosion. A set of ND W25EDR14 plugs lasted me 10K miles with no loss of insulator material and only normal electrode rounding.
Only bad part for me was finding them....ended up scoring a set from the Toyota dealer.

 

Thanks for all your help. I put in a new set of NGK's and set the idel speed to just under 1000 rpms....ahhhh my little 7 is amazing to drive now! I have only had it running for 3 days so I am having a blast with it!!!

 

glad to hear it. remember, to those who dont have much experience with the FB/SA, the 79-80 takes a 3 prong NGK ONLY plug. i have heard of rotary owners messing up engines with their choice of autolites and plugs seizing when using champion.

 

denso and ngk are ok
autolite is satan