Hi there, I bought a rebuilt RS lump and I've fitted it into my MK5 escort and I'm having a few troubles and was wondering if anyone could give me a few pointers...oh and its MFI

It's difficult to start and I have to rev it to get it going and it usually doesn't start first time.

When lightly accelerating the car hesitates and it doesn't feel like the turbos spooling and if I accelerate a bit harder it seems to clear itself and the turbo spools and the car feels "ok" and it'll then start to do it again. There are also flames coming out of the exhaust so it must be overfuelling.

To be honest I'm a bit stuck and I'm not sure what is wrong, any help or pointers would be greatly appreciated!!