be as many version as I can think of! 4/6/8/10/11 blade configurations are all possible. The 2283 7+7 that I'm using now was designed so the dreaded surge was eliminated. Once we've tested Gops version a decision will be made on which we run.. But as we are at the flow limit of the physical size of the compressor I think all gops might do is be more effecient or not ie flow the same but be in a better or worse % effeciency which will reduce or increase the charge temps which may aid timing .
One me thing is for sure a nice set of 630cc will go well with these