View Full Version : Intake manifold risers - god or bad?

03-11-2011, 08:46 PM
I am rebuilding my 401 and am thinking about using a set of 1" thick intake manifold risers. I am getting conflicting info on whether they help or hurt performance. Anybody have any experience with these?

03-19-2011, 04:54 AM
We lost 10HP & 15ft lbs. of torque on our engine. I've heard of others with the same or worse. IMHO their only good for raising the manifold to get linkage clearance with some multi carb. set-ups.