I have a 90se with intake, high flow cat,cat back, jetchip, grounding kit, and I just got NGK Iridium Plugs. Is there any known gapping # that out performs stock gap #.

 

nope, stock is best.

 

If you add a Higher output coil then you can open up the gap for some more power.

 

The pre-set gap for all NGK Iridium IX is 0.039" which means, I don't think you really need to set them at all. But you should check the gap with a spark plug gauges that you could get from the store. If yours is like mine, which is 0.039", I wouldn't bother changing them since Iridium are designed to take more beatings than regular plugs, leaving at that low number would give you better fuel economy and power since the fire power is a lot quicker.

 

thanks guyz, ill keep the at the pre set.