Phat-
A true IR Dominator intake while using the larger 1150 cfm carbs can only feed a 350 cid engine @ 8,500 RPMs. The late Bill 'Grumpy' Jenkins was a master at making them work on a 331 cid drag engine. Yes, there were 'some' experimental 4500 series Dominators made, but proved to be unsuccessful. That said, the original sand cast IR Dominators, as you may recall were used on 302 cid engines for Trans-Am competition. Btw, there was never any big-block Dominator IR intakes made (regardless of brand) as I mentioned, not enough carbs to feed it. Fuel injection, and two Autolite 'B' 1425 cfm Inline carbs and the rare Weber 58mm carbs will feed the large big-block Weber IR type intakes….but that is a different topic.