[JantzenOKC]

I've been doing some winter time modding. Making some changes to my evac system to help handle the extra crankcase pressure that came with forging the motor.

I've been running the Elite E2-X Ultra can since I finished the engine build. It does a great job catching oil but the clean side separator just can't move enough air to vent the pressure while in boost. My motor was setup very loose(maybe a little too loose on the ring gap..) to be able to handle HUGE boost and the abuse I'll be putting it through. Well this resulted in a lot of blow-by. The plan was to keep a suction on the crankcase at all times even when in boost but that's just not going to be possible with this motor the way it was built. I even tried setting up an electric vacuum pump that came on automatically off a Hobbs switch anytime it saw boost. But even with that pump running it still pressurizes and wants to blow the clean side separator out of the oil cap on my 1/4 mile runs.

So I think I've put together an evac system that can do a good job evacuating the engine at idle and during cruise but then when I go into boost it will allow all the pressure to vent out and not pressurize my crankcase.

I pulled my passenger side valve cover and drilled a 3/4" hole above the baffle and tapped it with a 1/2"x14 tap. Then put a 1/2NPT to -12AN fitting in it. I was able to cheat and used a 3/4" wood hole saw. Not made for aluminum but it was such soft metal it worked fine(not sure I would have attempted without having an old valve cover to practice on). $4 for that bit versus $20-$30 for a standard drill bit in a size that big.

Then I converted my old MightyMouse pcv can to a straight one way breather can. Just one -12AN 3/4" hose going from can to valve cover. This has the rubber disc on top of the can underneath the filter that seals when the crankcase sees vacuum (idle and cruising) and freely opens when the crankcase sees pressure(during 20# boost).