you dont want to polish anything but the exhaust , boost and tranfers work much better when a rougher texture is used for better fuel atomization. he exhaust port works well with a polished finish.
"porting" a firecat motor is hard to do due to the fact there is no steel sleeve . the firecat motors are nicacil bores and much harder to do "port" work to. the most you can do is a slight clean up job and get them as even and matched as possible(blueprinted). nicacil is very very hard but will chip easy on an edge . you must be very careful to attempt this yourself because you must have the proper chamfer on all the port openings or else chipping,delamination could happen. worse case would be you could catch a ring . if you want a true "porting" job done youll need to have your cyls sent out after and have them re nicaciled . most racers just bore the cyl and have steel sleeves pressed in then there is no reason for nicaciling. i myself prefer the nic motors fore reliability and the peace of mind that the cyl will expand pretty much at the same rate as the piston for less chance of seizures. always ask whoever is going to do your cyls exactly what is going to be done and what the end result will be ."porting" is really to change the port timing and allowin for more air fuel getting into the motor and helping to make more power . same goes for the exhaust port the higher it goes the more power it can make but like i said you cant raise the ports in a nic motor ...................
Just going through some old archives. F5, hate to say it, but you CAN port nicil cylinders. You CAN raise exhaust ports in nicil motors. Yamaha has nicil cylinders and people have been porting them, and raising exhaust ports for years. I speak from experience. Have done it. Yes, it is a little tricky, but there is a TON of power to be had, jusk like in sleeved cylinders.
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