3.5 & 3.9 exhaust manifolds

Hi All

Can anyone tell me the difference between 3.5 & 3.9 exhaust manifolds? I've got a 3.5 ex mil. 110 in need of a new exhaust system & I've been advised to replace the current 3.5 manifolds with manifolds from a 3.9 Disco 'cause they have a better finish / larger ports prior to fitting a custom system.

Many thanks

it is reckoned that you can see about a 10 per cent increase in from changing your exhaust for a performance system so seeing as land rover have already done a lot of the hard work i think it would be a good idea, also look at blueprinting the manifold with the head, matching the ports, maybe look for a freeflow manifold, TVR etc. Lee

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