Exhaust header port matching

[fischer550]

How far into the bore of the exhaust header should I dremel to port match it?

 

[BarelyAWake]

If it's a stock two stroke kit, you can only go so far as the port's ID is larger then the pipe's OD, you'll cut through should you try to make them the same - better to round the edges, blending the transition;

...you may wish to skip to these posts: http://motorbicycling.com/showpost.php?p=164391&postcount=25 & http://motorbicycling.com/showpost.php?p=164403&postcount=27 as the stock intake and exhaust manifolds are really restrictive, their gaskets and mounting flanges way too small - it's an easy & quick fix that should be done regardless if you intend to do the rest of the engine.