If your wanting to squeeze a Honda B16a2 vtec into a standard length roundnose and have no fabrication/welding skills you will need a custom exhaust manifold, unless you are making your own frame then you may be able to use the original honda one. But for most of us we need to go custom, especially if you are using the allspeed frame like me and don't wish to extend the nose or go clubman.
You still have to get around the radiator/alternator and inlet manifold problems but this topic is just for the exhaust side of things. There used to be a purpose built manifold available just for this (which minidan has on his project) but unfortunately the guy stopped running the shop over on 16v mini club a while back.
I've managed to find the company who made it though by luck as I called up a place that has made a back box on one of my previous cars (mr2 turbo) quite some time ago and the work was top notch so I thought I'd try them again. As soon as I said mini-vtec the guy told me he had previously made a few for a chap who sold them on through a forum, I realised this was the supplier
Its Haywards and Scott based in basildon essex, they have the jig there so no need to take your car up to get it measured if your using the B16a2 engine
Price is £550 plus VAT and your looking around 4-6 weeks for completion, however he did mention after about march time they can get extremely busy so completion times may vary.
Apologies in advance for my lack of tech knowledge, but these are a 4-2-1 setup, flange is 1 3/4", middle section at bends is 2" and end section is 2 1/2", I'm also getting a slip on reducer made if I deicide to use a 2" mini pipe.
I contacted maniflow and got quoted around the same price but they will need your car, these used to be on the old 16v shop at £600 aswell. I've ordered mine yesterday so thats one less headache to worry about.
If you do need one, give them a call (link above) and ask for Ian and say Kam sent you his way.
Hth
