Newbie to reading plugs, looking for some help. I've got a fresh motor that I'm just starting to tune on. SBF, 10:1 compression, twins, air to water. Trying to start out safe and tweak from there. These pics show my plugs after a single 1/8th mile pass, driven back to the pit. #3 looks fattest, #5 leanest. The last pic shows the straps. Can't see much of a timing mark on any of them (note: dark straps I rubbed the residue off with my thumb looking for timing mark). This pass was 18* total, 11psi, 100 unleaded fuel, 10.4 A/F ratio.

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First and last of the middle row looks like it could take a little more timing. The timing lines arent very well defined, but you can see the area of discoloration. AFR is pretty fat which could skew things some. Might be able to put a couple degrees into it, see what it did with the AFR and then try and bring it up to 11.

 

why go through all that trouble and drive it back to the pits? tow it back and your plug reading will be more accurate.......if im alone at the track, i just pull over on the return road and pull the the leanest cylinder plug and see where im at.