There is some inaccurate info in this thread. First, maybe someone straightened it up, but the Cobra cam is different than the GT cam. 1.7 rockers weren't just to avoid using a different cam, jeesh. You can run 1.72 rockers with any cam, as long as you make sure the results are what you want. I've built too many engines with 1.72s to let this info be posted as gospel. I'll tell you a helluva combo . . . . done a couple engines with this. Run a "B" cam with 1.72s. Terrific engine combo. One of mine ran 12.8 ET in total street trim, total, with this cam rocker combo.