I just got done with a full engine rebuild. All new bearings, cam, lifters, timing, dizzy... the works. It fired up and idles strong. But it feels like its struggling under load. It accelerates and gets going but not as smoth as i`d like. Timing is at 6 bdc. I have huge concerns about the fuel tank and supply system. For example, lots of pressure release when opening the gas cap after a few miles of driving. Ive done alot of research on the tank recall (supposedly done years ago says Rover), and different concerns with the venting system, and think thats where my problem lies. Soemthing just doesnt seem right. I used a pressure gauge that actually fits the shrader and its reading 34 psi with pump on, 30 psi at idle, then it starts fluctuating between 25-32 under load. Do those numbers sound right? The regulator is fairly new, newish filter, and rebuilt pump ( all within 5k miles), injectors were cleaned and tested about 500 miles ago. I even have the venting issue with the vent line at the cannister from the tank just venting to atmosphere (as some in AU dont have charcoal at all and its just looped right to plenum). Thoughts from the group? Am i chasing the right gremlin here? Something else that i thought about was maybe back pressure as i have deleted my cats... ? Possible?