Trial fitment and mock-up begins. Stats: LS2 block, resleeved with 4.125" Darton cylinder sleeves. Block has been align-honed for ARP main studs, decked, etc. The new sleeves make the engine block stronger, while allowing up to a 4.185" bore. Shot out to Steve, down at R.E.D. in So-Cal. Those are GM LS7 heads that have been re CNC machined. FWIW, they flow 401 cfm @ .700 lift. The intake manifold is a LSX/LS7, 4150 flange, single plane model. GM never made one of these models, for EFI .