Ok, what made you decide to open up the reed area? Off the top of my head i would guess that you would normally raise the cylinder ports by removing a little material on the top side but not too much that a ring will catch it. Porting is sort of a way to fix mistakes and make corrections in a cylinder to get maximum efficiency, thus making power.
Porting out all the passage-ways to get the max flow is the goal. I believe one way to get the best flow is on a flow bench using a special fluid that is forced through the ports it's carves away any inefficiencies like castings, webs, and sharp edges. That is for those hard-to-reach areas. For the do it your self 'er you could buy a blueprinting kit from a tried & true company and do the porting yourself......but it is very tidious. Indexing may also be required, i'm not sure. I have no idea what is the best solution on a T-cat, but hope this helpes some. IMO
Porting can add a lot of a horsepower to the Thunder Cat motor if done properly. A few of my freinds have had their T-Cats ported and they are rockets. Be careful who ports your motor. You can get hosed by some of the major performance shops. They like to clean up your exhaust ports and leave everything else untouched. Ask questions before you have your cylinders done. I'm curious about the reasons of opening up your reed area? If your going to do it your self be careful. If done wrong you can actually loose horsepower of torque.
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