Headgasket? Or Piston Rings? :(

[KiwiRS4T]

No, I set this engine to the standard 15* using the cam and crank marks, then a light.. but I then backed the CAS off 2mm Clockwise which would equate to 12* timing..

Wrong wrong wrong. Backing the CAS off 2mm = guesswork.

If you want 12 deg mark it on the pulley and set it with the timing light. Why do you want 12 deg anyway?

[Ben C34]

Because it's not tuned?

[GTSBoy]

I tune my car with a pair of bream. I slap them together over the top of the engine whilst humming furiously. I find that having an amethyst crystal clenched between my teeth makes it better.

[admS15]

I tune my car with a pair of bream. I slap them together over the top of the engine whilst humming furiously. I find that having an amethyst crystal clenched between my teeth makes it better.

I use a pair of snapper. Each to their own I suppose.