ok i have mazda spark plugs for a FC and im wondering if they will work on a FD.

the plugs are Mazda NGK SD10A and SD11A

 

Those are some pretty cold plugs. I did a search on ngk.com, and found that the plugs are obsolete and are not made anymore. Your FD would have to be pretty damn modded to take advantage of plugs with that heat range--I run similar ones. They're suited more towards high boost and high rpm driving--worst case they'll just foul quickly.

Can you post a pic?

 

yeah i will post pics in a min. i gotta wait for the other comp tho.

my dad bought them a while ago cuz they're for my dads old RX-7...... i guess they used to come stock..... and he never used them cuz he bought a few sets....

i have 2 sets if u wanna buy one..

 

ok heres the pics

 

ok no pics heh.....

http://superspeedimports.homestead.com/files/ngk1.jpg

http://superspeedimports.homestead.com/files/ngk2.jpg

http://superspeedimports.homestead.com/files/ngk3.jpg

http://superspeedimports.homestead.com/files/ngk4.jpg

http://superspeedimports.homestead.com/files/ngk5.jpg

http://superspeedimports.homestead.com/files/ngk6.jpg

http://superspeedimports.homestead.com/files/ngk7.jpg

 

Um, do you have any pics of the actual plug (to include the electrode) instead of just the boxes ?

 

The 10 and 11 do not correspond to the plugs heat range, at least not according to the research I have done. See my site for more details.

 

Ah, gotcha. They're just 7s and 9s. If I could've seen pics of the plugs, I prolly would've known that .

From my experience with spark plugs, with my setup and running 15-17 psi on the BNRs I definitely need the NGK race plugs. I get high rpm breakup with the 9s. I also have a jacobs on a "race" (fc) leading coil. Also, I once gained 18 rwhp (from 310 to 328) simply from changing from 9s to 10.5s. This was with full boltons and stock twins at 13-14 psi.

Nice site, btw.

 

hold up ill post pics of the actual plugs in a sec.