OK, for some reason, my 350 runs significantly richer on the front two cylinders than on the rest.
It has an Edelbrock Performer RPM manifold on double hump (1.940) heads and a Holley 650. The front jets are 68s and the rears 72s.

I just tore it down to install a set of Trickflow 195s an Edelbrock Airgap and a set of stainless roller rockers. Looking at the pistons and valves on the old heads confirmed that the front cylinders were running rich...any ideas??

Mike