I measured all my header pipes and they all run around 230 at idle with the exception of #6 which is running at 400* They were measured with an infrared temp gun at idle after a 25 mile cruise down I-94 to work. My Datamaster logs show the right side lean at idle, and then richer than the left at cruise (1800 rpm) Then the right side evens out with the left side when I bump up the rpm to +2500 rpm in the same cell. What should I look for on #6? Spark gap, clogged injector,?? BTW I've got new plugs and wires on. And just did a heads/cam swap CC233/242-.569/.576 cam ported stockvalve heads and Edelbrock shorty headers with no cat.
TIA
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Lean is hot so I would start with the injector. What brand are they? Maybe you got a bad injector that flows less then the others. You could try swapping injectors (#6 and #8)to see if the problem moves with the injector.