Originally Posted by hcompton
Not sure why anyone is telling you the ports dont need to match they surely do need to match. If they dont it will unbalance the engine at high rpm and it will make less power. One bad port can drag along and slow the engines total rpm loosing a thousand rpm can mean 100 hp.
If you use a shop vac to suck the chips down the port andout the valve side you can kinda see how the air flows incents or a cigg can give you a smoke trail to follow. Stright line of smoke means good flow stalling or circling air is poor flow. But way to much to explain in this little box.
Also keeps iron dust from causeing damage around the shop. Forgot to mention this but dont port near your painted cars the rusting chips will screw up your paint. Also not good for lungs and any other things you can think of.
Less is more just cut the casting marks smooth and flat and stick the heads on the car. Also try to do all the ports at once one cut per port makes them easier to match up and prevents you from spending 20 hours on the first port and needing another 120 hours of work to complete.
We wernt saying they don't need to match, just that your not going to get exact, and that's OK, the OP was essentially being told that hand porting is a waste of time, and that with today's cnc machines or high dollar out of the box heads, that it was a waste of time and performance will be unimproved doing it by hand. And that's ridiculous, yes, always try and match, and don't go and just hog the the hell out of the ports, but with some time, and patience, and lots of reading and learning what works, he isn't going to hurt anything, and will improve flow, and performance. Your right, a clearly bad port that doesn't come close to flowing what the next port does is bad, but your going to get close, from experience, your going to go back to the first couple you did, and see they aren't the same as the ones you just did, and your going to work a little more, and get everything close. And they will make power.....bottom line is, just because its old fashioned or antiquated doesn't mean it won't work. If that were the case my wife would have replaced me with a 20yr old pool boy years ago.