Breathing/Idle Problems??
 

Hey Guys i finally got my fresh imported RB on the road i was stoked for about 2hours till i was taking it for its first legal drive i heard a huge backfire louder then normal. Now everytime its warm and i let it idle it sounds as if it has breathing problems, it revs up to 2,500rpm then it chokes and drops to 2,000rpm and just keeps doing it, Ive been to the only Rotary mechanic in Nelson, NZ and he seems to think its a blown inlet manifold gasket but im not sure as it only comes from one of my apexi pods, has anyone else encountered something like this?
There is an attached picture to show where the noise is coming from.

Also once its warm it take a very long time for the engine and everything to cool down i mean hours after hours.
After taking it for a 1 hour drive with reasonably fast driving i went to work at 10pm i had it parked up till 4am till i had my break and went to the shop and it took mere seconds to get back to normal operating temp, also once warm i only need to hold a bag of cigarette filters by the exhaust for 10 seconds and it blows the bottom of it off. I cant work on it or even look under the hood while its warmed the heat just burns my face and even the gaurds are too hot to put my hands on, any explanation to why its soo hot? Maybe an AirLock ive been told but i got no idea what that means

I have tried to explain best i can with as much scenarios as i have faced to help anyone understand and maybe help

Thanks for taking the time to read this and any help/ideas will be much appreciated