We had a problem with my altered. We put on a pcv system. We'll see if it helps. I already had the lines from the valve covers to the headers. My headers are too big for my combo (thye came with the car). So I wasn't getting the exhaust pulse for them to work properly. So I could've upped the compression, bought new headers, or bought a vacuum pump. All expensive alternatives.Instead we're going to try the pcv.