In the US, we used to run the 235mm car. I used to run a big block 15 in mine, but then Serpent came out with the small block motor kit and I dropped in a small block 5 port 15. There was more than enough power to run that car. Now, if you have a 200mm car we run .12 with three ports. Very predictable and controlable motor. If you have a huge track and just want the all out scream go .12-5 port.

There was an outlaw type class 220mm that showed up two years ago in the US that used the larger front and rear like the old 235 cars and the rules permitted the use of 5 port .12 motors. Those cars ran great with those 5 ports. A small block .15 in a 220mm car is a bit overkill.

I like the 3 port because you can control the power a lot better. Again, in the US the 3 port motor is the standard when it comes to competitive 200mm racing. I run the Novarossi 353, 12SCT & 12SC. All in 3 port. These motors are beast!! I love them! In some cases they are too much power for parking lot style tracks.