After x pipe....

I don't care if he's Jesus. It's wrong. The X pipe made it go leaner, which is exactly what it is supposed to do. That's why the power it's making at idle changed, and as a result the idle changed. But like I said if you're at 1100-1200. the carb's not on the idle circuit entirely. So it's going to be harder to tune trying to use the idle mixture screws. You need to set the timing curve, lower the idle rpm, then re-tune the mixture screws to the highest vacuum reading at your final idle speed.