I have a 1995 mustang gt automatic with a built engine, it has a 331 stroker kit, stage 2 trick flow top end kit that comes with the trick flow stage 2 camshaft and full exhaust with x pipe high flow mufflers and around 10.5/1 compression. I just bought this car and the past owner gave me 2 SCT tuning chips saying that all I need to do is take my car to a dyno shop and get it tuned. Well, the car has been at a "professional dyno tuning shop" for the past week and I recently received an email saying he can't get the car to run leaner he said the car is too rich and doesn't know why.

Any advice?!?!?!?!?

 

I'd honestly take it to a different tuner, the good ones should be able to tell you what the issue is, maybe you need an fuel pressure regulator? Injectors to big (should be able to tune around that though)