A few hickups

The engine is back in, cables and pipes tidies up. Turned the engine over a few times without coil overs connected to get oil pressure up and then started it for real. Kept stalling directly and the only way to keep it going was to rev to 4000 revs or so. It sounded as though the firing order was wrong but that's basically impossible because all the cables are all cut to the correct length. 

One thing I did do while the engine was out was shorten the length of  the cables to the coil overs as they were unnecessarily long. I thought I had perhaps wired them incorrectly but I buzzed all the cables out and they were okay. I checked the plugs and they were coated in carbon which means too rich. I have now disconnected the MAF and directly it runs much better, not perfect but at least it stops stalling. Still the idle is quite erratic and the new vent valve (can't remember the name of it but it was replaced when installing the SC) is moving in and out continuously.

The only thing I may have done differently this time is torque everything to the exact specification whereas the first time I put the engine in I didn't have a decent torque wrench! 

Any ideas why it's running like this would be greatly appreciated.....

..... Thanks for the help Dave, James and Taffy.

I have tried a few things and have a few things left including replacing lambda. I will also change the MAF as I bought a cheap aftermarket one before. This is what it sounds so far .....

While this is going on I'm starting to prototype the air intake. I intend to encase the air filter with an opening to a hole in the bottom.

Once the shape is correct I'll cut it out from aluminium sheet. The idea is it will fit snugly up against the bonnet. All the nice cold air should go straight to the air filter!