1970coupe

http://youtube.com/watch?v=M5EH9ikkxQY

whats up with this? everyone responding says he disconnect the hose? what hose?i didnt even know you could get that affect by doing that. is that bad for your block?

heck if it sounds good like a cam and doesnt affect the motor i just might try that. haha

1970coupe

probably a pretty dumb question huh. just curious.

tarafied1

A vacuum leak will cause an engine to run lean on a carburated engine and idle rough. I don't know enough about the EFI to know for sure but I suspect the computer would try to compensate for a lean mixture or give fault code (engine light) and or more fuel. My 92 T-bird HO 5.0 EFI has a lumpy idle and it doesn't have a vacuum leak.
The high RPM type cam has valve overlap atlow RPM meaning the intake opens before the exhaust is fully closed. This causes the lumpy idle. Again I don't know why some there said cams wouldn't do that on a late model. If they have valve overlap it's gonna do it no matter what.
I wouldn't cause your engine to have a vacuum leak and run lean, you can burn a piston or valves doing that.