I bought the Dynatech system for mine. Takes the guess work out. It provides the correct depth and angle and gives you an 18mm thread incase you would want to install an 02 sensor. The part number at jegs is 329-85-100950.

If you are running mufflers the evac tubes aren't going to work. Any back pressure at all and the valve will close causing the engine to pressurize. I fought this for years and finally just installed a GZ vacuum pump.

Based on your discription of the angle tube depth ( 1/8" off the wall) Brian, sounds like there is a low pressure area along the pipe wall verses in the middle of the pipe? I have room issues trying to mount the tubes in the header collector - not to mention I aint drilling holes in my new headers. I do run the short extensions at the track. I also have a very minimal exhaust system ( 3" pipe to large chambered mufflers that dump in front of the axle ). I only run this system for street T&T or running the car in the garage - want to maintain my "good neighbor" relationship . I was thinking about running my existing PCV system ( slight negative pressure at idle only )along with the exhaust evac system. Any thoughts on that?

Depending on the muffler, it will or wont work. We ran the bullets and it worked, but went to flow masters and wouldn't. My brother runs them with mufflers but he placed the tubes after the mufflers. It doesnt work as well though...

I say if you have the $ and space just buy a vacuum pump and be done with it. You will never have another oil leak and will pick up 20-30hp

Chambered mufflers will not work with an evac.