I have just been told by a bloke in the pub (unimpeachable source, maybe) that old Xflow ,pinto, A&B ser etc can no longer be used in a new build requiring IVA . Because of emissions. Is this so?
ACC8BRAMAN is correct, you can fit any engine and the exhaust emissions test is described in section 02B of the IVA manual.
However, you must be able to prove the age of the engine and VOSA will be looking for some documentation from the engine manufacturer. This may be difficult for older engines from Ford as I'm not sure they will help.
BMW customer service (and maybe others) will provide you with a letter for their engines but I don't know if Ford do the same.