Just looking at the pics you provided I can say with 90% surety that those are one and the same CCCN Magnum replacement heads AKA Chinesium. I cannot see them approaching 250-260 cfm without a TON of work. I can still order those from my supplier and revisit them but until I get struck with a masochistic urge I won't. J.Rob
They're all chinesium, thought we've grasped that by now. Hey and you were just working on some x heads, those need much ssr work to hit 270. These you dont have to spend tim on the massive guide.
Next to a cracked mag head at the shop, the intake port is a lot bigger and has a better floor approach. You can put your middle and ring fingers right over the ssr, its pretty Wide. Other than that, they have the same massive pinch and they do NOT have the material to open them up like a RHS head, which i also have.
With the 2.02 i don't see it as being difficult or a ton of work, so ill use that as motivation.
With marginal type parts, if theyre better in some way.. i keep the optimism charged till the final word is in. Keep in mind there were a ton of people on this site claiming a stock mag head was superior to a j head and that "250 cfm was easy".
250/260 should be cake. Ordering some pro max pretty soon.