of course it's better to have perfect alignment. However, the air is being "pulled" into the head by the piston instead of being "pushed" into the head. I've done this so many times, and never had a bad experience. In fact, i just pulled a factory cast 340 intake off my 318 with 318 heads, and installed a Holley SD intake with 318 ports. So far, the cast has run almost tenth faster and more mph. I'm going to work with it a little more, then perhaps try another intake .... all for funs.
