After swapping looms over today and everything else that has been a total nightmare I finally got the engine started first turn of the key. It runs but Idle is a little fluctuant, it sounds like it's miss firing but it's not, the exhaust is pumping out serious amount of pressure.

Sounds to me like timing is out?

I removed the brand new Renault spark plugs and all 4 were black (over fueling??)

Obviously I did not let the engine warm up and switched it off.

The engine is running Vernier's and 261 cams...Will post pictures of the plugs up in a sec...Any ideas lads? Craig :(