EXHUASTS - back pressure ?
 

just looking into building a zorst for my type 3, what's the score with having back pressure for a type 4 motor ? do i need it or will a straight thru system do ? - mainly asking to decide on my choice of muffler.

cheers

Angelo

since i am no expert, i can only go on what i have heard. the most reliable info i have receive would be from jake. the amount of backpressure you need depends on what you are running. some level of backpressure is desired though. i am running a 2316 with a BAS silencer system and he tells me that it is about right. maybe slightly to the restrictive side, but about right for my application.

you may want to ask him on his forum on STF.

According to one of the employees at BAS, they have had engines up to 200 hp with that silencer system... but I agree Zen, I *think* it looks a bit restrictive too...

well, i am running 176 HP with the full exhaust and 185 HP without. so i am near their upper limit. will have it back on the road with full exhaust soon. thought about eliminating one of the muffs, but haven't decided.