mr0pistons

I am a newbie to the rotary world, and have heard a lot about this thing you guys like to call street porting. I saw somewhere that someone bought some kit or something from some website...can't remember what it was(rotorsportracing or something). However, I have no clue as to what it is or does. I am asking for someone to explain to me or point me in the direction of someone else, as to what it is, what the process is and what takes place, approx. how much it costs, and if there are any power gains? I appreciate your help, and sorry for the repost, please don't flame me.

EDIT: The car that this would be done to would be a FC.

karism

Streetporting is when you enlarge the intake ports a certain amount .This gives the port more open time,and it is also a bit larger flowing more gas.(like adding a hotter cam to a "boinger" or piston motor).

Mazdatrix sells templates to port from Streetport,right through to Bridgeport.

If you didnt know : Your engine will have to be opened to be able to port it.
http://www.autospeed.com/cms/article.html?&A=0389&P=1
<<<< On this website,you can read about porting

If you have any more questions,feel free to ask.

Karis

mr0pistons

so it is kind of like a port and polish??? What kind of power gain would I get?

karism

Depends on your engine setup.Are you running 12A or 13B. There is a slight resemblance to it (porting,and gasflowing)

mr0pistons

13B

BDC

It's comparatively-speaking the same thing from the piston world to the rotary world. Power gains are going to be subjective depending on the modifications done to the engine and other stuff around it (turbocharger, etc.)

B

Seldon

I've read all the posts on the forum about "bridgeports". What's the difference between a "bridgeport", a "raceport", and a "streetport"?? I got the idea that a raceport was simply a more extreme streetport, but is the bridgeport a port job in which a different port is cut??

Also, a number of people mentioned that bridgeports last 20k-50k (at best). Is this also true of streetports??
What about the low end power loss? Is this a problem with a streetport?

Sorry about the n00b behavior (as in my complete lack of knowledge about porting)
john

rotaspec

Yes, a bridge of metal is left between the old port (usually extended like a streetport) and the newly cut port beside it, hence the name bridgeport. The bridge has to be there to support the corner and apex seals, or they would just fall out of the rotor into the big port.

Think of the different porting types as similar to various lift cams. The longer the port (street or extend type), the longer the duration of intake. The same is done to the exhaust port. Because you can only lengthen the port so far (before you hit water), the only way to gain more intake timing is to go sideways with the port (hence the bridgeport). Because the rotor traces an arc as it passes the port, a new port beside the old even though it is at the same height when you look at it, will open earlier than the original one.
A properly done small bridgeport (that doesn't cut into the water seals or jacket) will last a long time and give good results. The more extreme bridgeports that cut into the water jacket area (and require blocking off the water jacket) are the shorter lived ones. Eventually they leak water into the port.
Streetports lose very little lowend power and give a noticeable increase in the top end. They are just as long lived as stock ports if the motor is treated the same.
Mazdatrix website has some good info and pictures of the various port jobs.