Thanks for your continued help and patience, I didn't run the engine before I pulled the heads and haven't asked the previous owner about the lifters which is why I want to contact the original US owner. Oil pressure is good 50 psi measured from a gauge not the sender unit and fascia panel but it stays at 50 from idle to 2000 rpm.I took her for a run yesterday and she goes like shit of a shovel but very bad manners, not good in traffic at all hard to start when hot very jerky in 1at and hesitant when you floor it. I will pull the timing cover and check the timing marks so I can rule it out as a possible cause but after that I'm out of ideas. Thanks again for the replies.
Here is my OPINION, I'm no expert, but sounds like it could be the cam that was chosen for the car. When the heads were off, did you notice if the tops of the pistons were either dished or just had the "eyebrows" for the valve reliefs?
If you have the factory style piston tops which have the 4 eyebrows for valve reliefs, plus the 1969 #48
heads with 72cc chambers, your compression on the 400 is up around 10.5 to 1. The car will need a premium gas or race gas with lots of octane. The Comp Cam with the 110 LSA would not be my choice for an engine with 10.5 compression if I were running it on the street. These cams do produce a lot of explosive power in the mid-range, but power will peak quickly and fall off - so the cam really needs a target RPM that it operates at and then a matching torque converter (if automatic), trans gearing & rear axle gearing. The car may hesitate when you stomp it because intake velocity has not been built up at the lower RPM's - this is why you run a 3.73, 3.90, or 4.11 gear in the rear axle or a higher stall converter (if automatic) - this also makes it more streetable and seemingly less jerky on the street. You my be able to compensate for some of the hesitation by adjusting your carb to give you a longer shot of gas from the accelerator pump.
Hard starting when hot can be due to incorrect distributor timing or a gas leak within the carb that seeps down into the intake to create a "rich" start problem. You can drop the distributor timing back a few degrees to see if this helps the hot start problem. Keep in mind that if you have the original factory harmonic balancer that the outer ring can slip on the inner rubber ring and give you a false distributor timing as the balancer timing marks will move if the ring slips.
I can't tell you what to do, but I would call or email Comp Cams and give them your engine build specs and the 270H cam your engine came with and the problems you are experiencing. They may recommend a different cam profile other than the one you have. The cam timing could be off and Comp Cams may even recommend advancing or retarding the cam you have, so I would call them first for their recommendations before you go into the timing cover.