Chainsaw Repair

Now free porting ,kinda deep .There is a phenominan termed resonant frequency which is used on tuned exhausts but also has been attempted on intake circuits .The only example I ever heard of that worked commercialy was one model of Villers motorcycle made in England probabely 50-60 years ago .I don't think they were totally successful or else they'd still be in business .

Theoretically what you have is at one small portion of the cycle where all three ports ,intake, transfer and exhaust are open drawing fuel directly from the carb .Complete purge of the incoming  charge .Coupled with a tuned exhaust it is a two cycle tuners degree of utopia .The theoretical  push pull circuit .Problem is at least so far nobody has been able to figure it out successfully because the RPM band it would work at is extremely narrow .Now that one is a bone to gnaw on .