At a glance they are close. I am going to try and use them in a dirt track car and pass them off as factory X heads. Our tech guys are chebby lovers and know little about mopars.

At a track or series with knowledgeable people....forget it.

My factory magnums are at 1.760 IH and I haven't had a problem. We cut the seat and used a +.050 retainer that Hughes has. We ran at 6800 MAX RPM. I do not build heads like some of these guys do. so take that for what it is worth.

Allen