you need to step into at least the 20th century...EPA emissions have been around for decades and look at all the new muscle cars power output compared to they days of yore, Corvettes, Hellcats, etc..EPA doesn't keep them gutless or run like ****

 

I will say this about external venting. I vented mine as an experiment and found so little oil in the catch can after a couple thousand miles I put it back to stock. People thought I was crazy but I did it for warranty reasons. Fast forward and I finally penned down a famous and we'll regarded tuner/builder about it. He said they don't bother venting to atmosphere as it isnt necessary. Said they tear down engines that have been vented to atmosphere from day one and they have just as much carbon buildup as those that havent. He said it makes zero difference on the dyno too. And his personal bike isn't vented to atmosphere. That was good enough for me. Vent it if it makes you feel better. But unless you have excessive oil coming out, which means you have a problem, there isn't much need to bother.

 

I think part of the problem is that historically Harley had to have tunes set very lean to barely meet EPA regs. This resulted in high running temps, less then optimal performance and also substantial improvements when aftermarket tunes were used. The M8 seems to be a more efficient motor that also seems to benefit less from the typical stage 1 tunes then the older motors.

Again, I think.

 

MJ, I'll have to jump in on this. LOL Your V6 may perform better, that I will not deny, however, it will never be as cool as the Charger 383 magnum....

 

we have a highly reputable SM at our dealership and he told me you still have to 'blow the carbon out' the old fashioned way on these which means not being afraid to run them 3500-4500 + rpms regularly..I suspect many spend the majority of their time in the 2500-3500 range which is useful but not doing the engine any favors if not going beyond that..and seems to me if you do this regularly the small amount of collected breather residue examples we see reported, being time released so to speak, renders it largely insignificant

 

Same as Spanish Cobra's set up, just a bit more HD lol

 

This is my 4th Harley and have rode them all hard. I believe they perform better with "blowing the carbon out" plus it is how I ride anyway.