I have a 72 Nova with a 355. My question has to do with the rocker arms on my dual pattern cam. I have heard that if you put 1.6 rockers on a dual pattern cam, you will loose power down low since you are increasing the overlap. I am running a Comp Cams XE 268 cam that is 224/230 @ 50/1000 and lift of .477/.480. I have also been told not to put the 1.6's on because it will put too much strain on the valve train. I just installed some Dart Iron Eagle 180 heads this week and I don't think that it will be a problem but I thought I would ask.

Here's one thing to remember about 16-valve V-8s: They are way undervalved! The more lift you can get, the better. You will not overstrain the valvetrain or cause a major increase overlap. 9 times out of 10 you will increase low and top end power. Just make sure the pushrods have clearance, and you springs can handle the extra lift.

Duration will increase roughly 2* @ 050 -- not really enough to notice (might extend your power band a hair), although the extra lift (usually about .030") will help power across the entire RPM band UNLESS the heads do not flow better at higher lifts OR the engine is already over-cammed.

Sometimes SBCs respond better to mixed rocker ratios -- like 1.6:1 rockers on the intake and 1.5:1 rockers on the exhaust.

Just make sure your current valve springs can handle the extra lift without coil bind before you make the switch. The Comp 981 springs intended for use with your cam are good to .500" lift, so you would be pushing it a bit with 1.6 rockers -- not sure what springs come on the Iron Eagle 180's though.