Leans out above 6500-7500 to air fuel ratoo of 18
 

New factory rx8 reman. Braking in slow and steady and all went well until we crossed over to 6500 rpm. Now it misfires and leans out. Replaced all fuel injectors and richened load and still some leaning out. Any suggestions?

Why did you replace all the fuel injectors and how did you "richened" the load?

Tell us the rest of the story :)

First assumption was bad secondary injectors or no signal to them. I haven't checked them with a noid yet.

Before replacing all 6 injectors I tweaked the ECU maps and that made absolutely no difference.

while replacing them yesterday I did find a kink in the fuel line that runs between the primary and secondary fuel rails. I fixed that and that seemed to have helped.

I need to go back now and reset the ECU to the previous settings.

Engine sounds and feels much stronger so I think the fuel line may have been the culprit. We are now getting larger flames from the exhaust (we use pre mix 1.5 oz. / gallon of gas) than we usually do.

Not much else I can think of that would cause the issue. If so please enlighten me.

Kinda a no brainer.....this likely was your problem :)

No fuel supply = lean ;)