Question, already searched
 

What is porting (on rotaries), and whats the difference between all the different types of porting? I looked in stickies, and upgrade threads, etc; and also searched for "what is porting" and "what is streetport" and "what is bridgeport", but the words "what" and "is" are too short so it just shows results for "porting" and "streetport" and "bridgeport", which everybody and their mother has mentioned, so it basically shows every thread on this site. Anybody want to answer this question, or link to somehwere where it has been answered, it would be much appreciated.

Thanks, Connor

Yeah bud, I had the same problem :)

Here's a link to help you;

http://www.mazdarotary.net/porting.htm

and this one's good too.

http://autospeed.com/cms/A_0389/article.html

Well worth the whole read!

Aleks

Okay, I'm starting to get it. So when you port, its on the actual rotor housing, and this is the intake side, not the exhaust side, right?

And with the mild/ectended port, you basically just take the stock bridge section out, and round the port a little?

well, probably the majority of port jobs are done to the intake side, but there are still a considerable amount done to the exhaust side. just gives you different results is all.

You are on the right track as far as intake porting, but no you shouldn't knock out the bridge section in a 6 port motor. (6 ports are n/a motor) The pictures of ports shown were on turbo motors, they don't have the bridge and the extra port on top.

If you take that bridge out you ale looking at a motor that only makes power close to 10K or so because the port is way to big.

Okay. Well the porting would most likely be done to an N/A 12A motor, if that would change anything around.

Yeah that changes things, I am pretty sure that US 12a's are 4 ports.