You will be more than fine, once you trim your boost down to 10psi.
http://www.wvinter.net/~flanham/wlan.../3modrule.html
The stock ECU runs pig rich. Given your fuel system is up to par, you should not have to worry. The ECU also compensates for a possible boost spike at transition.

 

OK then, one last question:

Would it help to switch them out and get them cleaned every oil change? I'm thinking I could rotate two sets like this, getting 10k total out of them?

Is this set already done? (or should I clean them first to decide that)

Dave

 

To be honest, I've never tried cleaning plugs, so I'm not sure how much it helps.

What I do know is that the car feels a lot better with fresh plugs, and they're relatively cheap and easy to replace. I've been replacing mine every 5-7k miles, and the old ones are looking pretty worn when I remove them.



Personally, I'd be worried about the electrodes on your old plugs, compared to brand new ones:



Here is a thread with lots of photos of used plugs: https://www.rx7club.com/3rd-generation-specific-1993-2002-16/post-your-spark-plug-photos-here-417119/


-s-

 

Your leading plugs are showing quite a bit of wear on both the electrode and the surface gap edges. You'd probably be better off replacing them.

Short of the plug being black with soot or showing abnormal combustion signs (metal flakes on electrode, melting of ground components, etc.-- by that point you have other more important problems), it's really a crap shoot to try and "read" your a/f ratios by examining a spark plug without running the engine at full throttle for extended periods and then doing a "plug chop" (which obviously isn't a feasible task on a street-driven FD). The coloration of the plug surface is always going to change otherwise, and just because the plug is white with ash deposits doesn't mean you're running lean.

 

Whoa, how did I miss that thread? I guess I didn't search well enough Mine look pretty normal it seems.

Thanks for the input all, I guess I need to put plug change into my maintenance plan every 2 or 3 oil changes. I knew FDs went through plugs quickly, but I figured that was only the modified cars that chewed them up in 10k.

Dave

 

10$ a plug isnt all that cheap....

 

try www.sparkplugs.com

-s-