Good advice from Rooman, we use flex hoses to and from the valve cover going to the vacuum pump and the puke tank.
If you notice , on the photo, we run our vacuum system different than most others. We had Jeff Johnson build an extra camber on top of the left valve cover, because we pull the vacuum from the oli pan not the valve cover. The idea is there is alot of oil in the valve cover at high RPM, that needs to drain thru the head and block to return to the oil pan. Most other racers are pulling vacuum from the valve cover which is pulling up the engine when the oil needs to go down the engine, so you are fighting the flow of oil. Again we have a fitting in the oil pan that gets hooked to the valve cover camber that gets hooked to the vacuum pump, and then the puke tank. There by the vacuum is being pulled down from the oil pan, not up to the vavle cover.
Last year we thought we had a problem with not enough vacuum and put a regular valve cover on her, but we noticed the rod bearings did not look as good, we normally get over 100-120 runs on our rod bearings, so we put the camber cover back on and now the bearings are looking great again. The camber cover has a few small holes into the VC to drain any oil to the cover.
Any questions feel free to call me, 805-444-4489
Jon