dunno i dont think so, i have just stripped my project which was a mk2 8v gti with a 16v engine in it, the standard 16v exhaust manifold on me engine fitted fine, ive just took the whole lot out, but im sure a 8v four branch wont fit but i might be wrong!!!, tsr do a good replacement manifold/four branch unit, if you need the manifold and down pipe off a 16v give me a shout as i have all the bits plus any more you may need!!!
Gaz