The 655s will make around 1150 but that is a total effort engine. Jesel, Belt drives, Titanium every thing, $$$$$$$ The only block that they will work on is a spread bore INdy. Very picky heads. I know that Todd Godwin was working on them to get them better but not sure how he did. Not for the faint of heart or wallet. Todd
Hey Cesar.. I have a supercharged Indy billet headed HEMI engine, fresh and ready to run that makes about 2300 hp that will twist your Dart real good if you are interested
We have a 600-13 engine in the dragster. Far from being anywhere near max effort deal for sure. Compression and cam are on the tamer side for sure. Single 4bbl wet sump deal. Made just short of 1100 on a dyno I know little about as it was the only time we have used it. We have been 7.20's and I believe 185 in Vegas in the summer with it in our suspended dragster. My first go around with these heads. It works well for what it is for sure. No complaints.
The heads use a 2.400 intake along with a 1.900 exhaust. To get the valves to fit you have to spread the bore centers of the block from 4.800 to 4.840. They start in the back of the block and move the bore center of the block as they machine each hole. To my knowledge Indy is the only block manufacturer that can or will do this. So no on the mega block. You would have to rotate the valves out of alignment like canted valve heads that are available. I guess you MIGHT be able to run smaller valves but then you are talking replacing all the seats. NOT advisable. Todd Godwin was looking into some things on these heads but I am not sure how far he got or what he was looking at doing. Todd