I just rebuilt and street-ported my NA. I've got around 600 miles on the rebuild. Compression is 90-90-90 both front and back. Idles at 1000 with poor power up through 4500. Spark plugs were checked at around 450 miles. Front rotor plugs=shiny & back rotor plugs=tan deposits. New plugs installed and exhibit exact same coloration after 150 miles. Spark appears the same both front and rear( as viewed by timing light triggering). Do I have an injector problem? My guess is the rear is normal and the front is not. I'm a bit of a "newbie" so any help is really appreciated!

 

what kinda plugs all around? shiney? ive never seen a shiney plug some outa a car, a nice tanish coco brown is what your lookingfor, white deposits are to lean, black are to rich( rx7 plugs soemtiems have black deposits anyway, mine are usually half coco, and half black, go figure) you dont want white, or oily lieks stuff on them

 

don't n/a ported engines get poor hp at lower rpms and better hp at higher rpms than a stock n/a?
not to mention ur engine only has 600 miles it's still breaking in (i belive) when it hits 1000-1500 miles then i would start driving it hard to see what it could do


-Shawn

 

Thanks guys! I feel a pretty good hit at 4000 when the secondaries kick in and it feels strong 5000-6300. I'll wait to see how things progress with the break-in but those plugs still puzzle me.

 

Im curious about this also.

 

Found the problem---front primary injector not firing( no gas present when I turned engine over with plugs removed & no change in idling if I pull both front plug wires). Swapped injector with another with no result so I'm a-gonna rewire the harness. Evidently the 15 year old harness did not take kindly to removal and installation when I did my rebuild.