so how much would another rotor cost if i wanted to make it a 3 rotor? and is it worth it? also, is it possible to make the motor be anything more than a 1.3? and how much would that cost?

 

You can't just slap on another rotor. It won't work. You'd have to have an entirely new engine and Mazda does not make a 3 rotor Renesis. This is basically like asking how hard would it be to add 2 more cylinders to a V8 to make a V10. Obviously it isn't easy and would take a new engine. Unfortunately you can not alter rotary displacement as you can a piston engine. You are pretty much stuck with a 1.3. If you are searching for more power, look to forced induction. That's your only real alternative.

 

It's not a simple matter of just adding a rotor. There are other significant modifications that must be made to the system to go to a 20B. Cost? Probably a few tens of thousands to do it right.

HINT: Use the search engine when you have questions like this. There are a number of threads discussing a 20B conversions and engine displacement. Search for 3-rotor or 20B for starters and you'll get lots of threads with good information.

 

building the 20b renesis is easy, you just buy the e shaft from a 20b, middle plate, rotor housing, rotor apex seal, oil rings, longer 20b engin bolts.
the hard part is making a 8 port intake, exhaust and ecu, also fitting into an 8.

 

^None of that will work.

 

http://cgi.ebay.com/ebaymotors/3-Rot...QQcmdZViewItem

 

That is not a Renesis engine.

 

^Holy crap where have you been!!!

 

I logged in and had 137,405 new posts

I've been trying to catch up.