Many here and elsewhere think Clifford exaggerates their HP gain claims somewhat. Maybe a heavily modified engine might reach the gains they say in my opinion. That being said, I do and have used a Clifford 4 bbl intake on a pretty stock 235 and a softly modified 261. Without a dyno check, but seat of the pants, my truck(and formerly '55 car) had the feel of more torque. So you will see some performance improvement in most cases I think.
