When does custom porting become beneficial?

[1980RS]

I think porting has more to do with not the size of the port, but more with the quality of the port after porting. A few years ago I took a chance on porting my set of L-29 BBC heads, Why? because no one else has messed with them much and they intrigued me to try to port something different. I already knew what people ran with the stock L-29 heads so I figured I had nothing to loose. After porting I went to the track and got a big surprise with the best 60ft and ET right off the trailer. Even though my lower end went away I was very happy with my results. How high did I run the engine? 6K that's it, so don't give up you might find what one person says doesn't work another person might say it does.