Regarding: Next Generation Mazda RX-7 back from the grave...

A 16X (1.6 liters) engine is ok, aceptable, and needed for the RX-8, but it is way too small for an RX-7 sport car. Mazda need to make the car with at least a 20B 3 rotor engine (2.0 liters) or even better a 24x (2.4 liters) 3 rotor version of the new 16x engine to be able to be competitive with the 3.0, 3.5 and 3.7 liters engines of competition (Infinity's, BMW's, etc).

I know that dreaming for Mazda to make the new RX-7 with a 4 rotor engine will be too much. But I know that if they make it with a 3 rotor engine specially if they make it with a 24x version it is going to sell like hot cakes. That all Mazda rotary engine lovers are going to sell their houses to buy one. And I will be the first one in the line to buy one. But if they come out with another 2 rotor engine, even if it is a bigger 16x version, don't count for me to be in the line at all.  

Really I think that the 13BTT engine is fine for an RX7... cutting the turboes was the mistake with the RX8. I wouldn't hesitate to buy a car that was 3 rotor from the factory, but at the moment I'm grabbing 470RWHP out of my RX7 so power can be made from a 1.3, but at the same time I wish there was a way to get more low end torque out of rotaries.  

I have been racing and modifing rotary engines since 1971. And I can not count how many RX-100, RX-2, RX-3 and RX-7 has pass by my hands with 10A, 12A, 13B and 20B's. And I hope soon I will be able to have a 4 rotor engine in my RX-7 Turbo.

But, Yes it is easy to make big time HP with a rotary engine. In fact you can make the same power with a 12A than with a 13B or a 20B when using Turbo or Nitrous. But the only way to make more torque, more HP, and at the same have a more reliable engine specially if it is for street is by using a bigger engine.

The proposed 16X (1600cc) is going to have more torque than the smaller 13B (1300cc) because is bigger but I still think Mazda should install a 3 or 4 rotor engine in them if they really want to make a car that everyone want or dream to buy. Mazda has been playing with 3,4, and even 5 rotor engines since 1970's and still keeps sending us their smaller engines. In fact the 20B was a mass production engine in Japan although only with automatic transmissions. The 12A (1200cc) engine size was ok in 1970, but even the 13B was small when it was introduced in the big and heavy RX-4 in 1974 and Cosmo, and the only reason it was popular at that time it was because we use to transplant them into lighter bodies.

But we are almost in 2010. A 1600cc engine for sport car that is going to have to compete in the market place and race tracks with 3,000cc BMW's with twin Turbos, Nissans and Infinitis with 3,700cc engines, and even with 3,800cc Hyundai Genesis is not enough. (Although the engine should be installed in the current RX-8 car as soon as possible because its current 1300cc engine is too small and don't have enough torque). And yes I know that a 3 or 4 rotor engine is going to drink a lot of gas (and oil) but people that buy sport cars dont buy them because they do 60 mpg.  

5 Rotor Engine? Are you sure Mazda built one for either their race or production car?? because I've never heard of 5 rotor, rotary engine. I've seen fake pictures of such and cad drawing done of a 5 rotor eshaft design by some company, but never by mazda themselves.

regarding to 16X... to me its not about the displacement but emission, efficiency of direct injection. Company such as Mazda is not looking to make high HP car that's completely useless on the street but something they can sell to general population who cares about MPG and driveability. If you actually look at the market, there are VERY small percentage of people who's willing to pay big dollars for a new car.. Just as many so called rotary guys who holds on to their rx7 and not going out to buy a new RX8... They use excuses of, "its not much better than my 7", but reality is not many can fork out 30s for the new 8 when they are driving close to 20 year old car.

If you actually owned and tracked the 8, they are amazing cars! Far more fun than any RX7s out of the box.

Also, anyone who's interested in 4 rotor MAZDA engine is just dreaming.. I've priced one before and short block itself is about 100K. Not only that, what would you put it in? What, your $10-20K RX7?  

One and 5 rotor engines were only prototypes. Never used for racing (to my knowledge) much less for production. Like the 15X and 16X engines which are also prototypes. The difference is that they were actually thinking about mass producing them. Hopefully for the RX-8 before is discontinued (by 2011).

Regarding the 4 rotor engine it is in no way that expensive to build. Specially if you use regular 2 spark plug housings instead of the 3 spark plug housings that Mazda uses (unless you had to pay $80k or $90k for someone to put it together
for you).

You can order the special parts that you need to Australia (around $10,000) and put it together yourself using good used parts from two or three 13B engines. It even works with two 13B intake manifolds and fuel injectors (or two 13B intakes with Holley or Webber carbs).