nitro tc rules?
 

i'm looking at the roar rules for nitro touring car and i'm a little confused on the allowed engines. it states .12 roar/ifmar engines only and that would be a maximum of 4 ports including the exhaust port. so there is no .12 open class (outlaw), run what you brung .12 5 port, or .15, .18 ?

You are correct, there is no outlaw class for touring car in ROAR. You must run a 3 port (it's 4 if you include the exhaust) engine, which is also the IFMAR rule.

This is true for ROAR races, like regionals or nationals. Local club tracks may allow .15 or .18 to accomodate those who have RTR cars.

Most racers I have spoken to like the 3 port rule because it puts at least some cost control on the engines. If you allow the 5 port engines you would see a huge price jump in engines that would price out many racers.