I don't think that Stage-V supplies the fuel rails, at least Eric didn't that last time I talked to him, but they are easy to make and fit on a HEMI manifold. Both Barton and Indy will do that for you, for a price. Injector length is easy to adapt for on any HEMI manifold so that should not be an issue.

As far as performance they are all about equal since they are just flowing air. Dual 4150 Accufabs look great and perform a little better than a single 4500 but not so much you would notice. With dual TBs you use only one TPS and one IAC.

BTW: I'd go Holley EFI.

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