PCV Plumbing
 

I'm planning the PCV plumbing on the LS3 in my '68 project car. I purchased the Spectre cold air kit which has no provision for fresh air to the passenger side valve cover. Rather than hack up the nicely ploished aluminum intake tube, I was wondering if I could use the indicated port on the throttle body. It's behind the TB blade, but clearly gets metered air.

Thoughts?

that would be vacuum and I believe it would make a fantastic whining noise if you used it as a pcv vent...I would run a tube to your air cleaner box to vent crank case. Thats is you had one.

Mike,

I don't know the answer but I just left mine blocked off as you have it. Subscribing to see opinions. I just drilled a hole in my Spectre elbow. I know it is not that clean but it seems to work.
http://i186.photobucket.com/albums/x...f/IMG_4611.jpg

Thanks for the picture. What size and type fitting did you use? I was thinking about trying something like that on the underside of the tube, but was wondering about how to seal a flat fitting against a curved surface.

By the way, is that a Norris catch can?

I'm no expert but from the reading I've done on PCV, it seems like you wouldn't want two equally strong vaccum forces. So one vaccum source behind the Tb and one in front is the recommended way to go.

This is the best info I've seen on PCV:

http://www.shophemi.com/images/media..._ccv_bible.pdf

Thanks, that's a great link.

Mike, I used a 5/16" (might have been a 1/4" don't remember)Hose barb fitting along with a thin retaining nut on inside.
Looks like this:http://images.drillspot.com/pimages/7277/727788_300.jpg

A welded fitting might look nicer. That is also a Norris catch can. Not sure if needed but I also have a catch can hooked up to driver side rear valve cover that runs to pass side.
http://i186.photobucket.com/albums/x...IMG_4647-1.jpg

Nice job tom, very clean...I hope you used lock tight on that nut.
You could weld a NPT bung to the underside of the tube.