eric e

hi all

slowly going through the 1993 FD i have just bought in japan, legit sale but no manual, sevice records etc.

though it was pretty standard but the deeper i dig the more i find

unfortunately previous owner looks to have been a dealer, he just had it 4 months and seemd to know less about the car than me

anyway, took out 3 of the plugs today and found they were, NGK-R R6794-11, leading, (forward leading plug was still too stiff for my liking after a full turn so i stopped, no need to rip out a thread just to clean a little crud off a plug!)

and NGK-R R6794-11, trailing

the NGK R was on the ceramic, (R meaning racing i guess...)and the R6794-10, R6794-11 were stamped into the metal

i've done a search in the forum and also tried to find them on NGK's webiste, but have so far drawn a blank

electrode was also different from the cross cut face of the stock plugs. single arm was flush with base and center electrode looked thin enough to be a platinum

anybody ever seen these things before and care to comment?

car starts and runs ok, has big bore apex pipe and HKS foam airfilters but that 11 in trailing is the coldest plug i've seen mentioned on this forum and looks pretty grubby...

eric e

sorry meant -10 leading and -11 trailing

leading plug photo attached

eric e

but it goes like stink

88fc3sw/HX83

Usually HEAVILY MODIFIED rotaries will run those plugs. If you're not making 450+ RWHP, BUR9EQ plugs should be good enough.