Just an update,
found the cause of the problem.
It wasnt the CAS, and it wasnt bad fuel.(I drained the tank and put new fuel still the same)
I figured it was a fuel problem though, sounded like fuel pressure.
So I went and bought a new fuel pump and removed the old one. (what a pain in the butt that was)
When I finally got the old pump out I noticed that the short black fuel hose that connects the top of the pump the the send fuel line had burst, it was split.
That explains the hissing/swooshing sound in the tank and low fuel pressure.
While I had it out I replaced the fuel pump and the hose etc with the new ones, put it back in and it runs beautiful.
Only problem is the fuel gauge is stuck on full with a 1/4 tank so I bent something but I dont really care the car runs now, Ill fix that later.
So lucky I didnt spend hours changing the CAS and then not solving the problem, but like I said, it had very good,regular spark, but anyway, solved the problem.
Thanks for all the advice fellas,
Much Appreciated.