I have attached previous and current #4 and #8 cylinder images for comparison. The history for #8 was slight head gasket leak causing a popping condition at higher rpm's, also evident was an immaculate intake valve underside, leaking valve seals as well.
"New" images reflect 1000 miles on new plugs since replacement of valve seals and head gaskets. AFR has been approx 11.0 during this period. Have not performed pulls past approx 5300rpm during this time. Maybe 100 hard pulls and the rest normal driving.
I have scheduled a couple hours on the dyno and request an evaluation based on the plugs. Also some tips when I am on the dyno would be much appreciated! Thanks...
One specific question I have is: If I set cutoff at 6200rpm, will the engine and dyno actually provide info up to this point, or should I target a slightly higher cutoff? ty
Additional: Appears #8 might be a little lean? I want to accommodate #7 and #8, should I enrich to 10.8 WOT?