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View Full Version : Thinking about getting a rx7..


Giozilla
09-01-2011, 06:36 PM
Hello I am new to this forum as well as rotaries.. I have always been into rotaries and the possibilities with them.

I am thinking of getting a second gen rx7 as a weekend project car. not a DD
I have a 2008 4dr si as a DD

I have a few questions about the rx7 though..

first
-which engine do i get? i hear all this stuff about 20b and 13b..
i get confused haha

whatever I get i want to turbo it haha..

Now whats the difference between bridgeport and pershport? ( I KNOW I SPELLED THAT WRONG PLEASE DO NOT FLAME)

the only thing i know about about rotary is how to maintain them..

well lets start with that first question and then i'll ask some more.. I am still a college student and still paying off my si. but i should be able to get it sometime next year . I want to do things RIGHT.

I was going to build the si. but i like it the way it is and as a DD and all the space it has.

I want the Rx7 as a fun street car and see some time attack time.

any ways.. hopefully everybody on here can teach me a few things about the great rotary =]

sidewaysFC
09-01-2011, 09:22 PM
Well any rx7 1985 and up is going to have a 13b .and a bridge port is were you make a slit going alonge the main port it will give you realy good top end power and an idle that sounds like BRAP BRAP BRAP BRAP and a p port is were your intake opening is on the roter housing it self

Giozilla
09-02-2011, 05:14 AM
Mhmm so does that mean I can do both ports?

sidewaysFC
09-03-2011, 09:57 AM
not realy you would have way 2 much air coming in, i mean it mite be possibul but ive never herd of any one doing that and you would have to figure out an intake manifold for such a set up. a bridge port would be easier and give you alot of power.

BoostedFC
09-03-2011, 08:04 PM
Okay pretty simple, there are different rotary engines in the Mazda line up. Most common will be your 12A, 13B, 13BT, 13B-RE, 13B- REW & 20B. All of these I just listed are all 2 rotor motors except the 20B which is a 3 rotor. There are others, but to keep things simple that's what will most likely hear about. The are FAQs that will help you out if you decide to read them. There are a few types of bridge porting (half bridge, full bridge & monster bridge ect.) It is called a Bridge port because in the process of getting more air into the engine a slit is cut into the plate parallel to the port & a bridge is left between them for the seal to ride along. Now Peripheral Ports are different completely as the stock ports are closed off & the intake ports are cut into the rotor housings themselves above the factory exhaust ports. There is a Semi-Peripheral port which the factory ports remain in the plates & small peripheral ports are cut into the housings. Manifolds will be interesting for these type motors. Read here for info on porting: http://www.rx7forums.com/forum/showthread.php?p=7899#post7899