mach 1 engine

2003 mach 1 Well I just rescently bought my 03 mach 1 after wanting one for so long and about 4 days after buyin it the check engine light came on. So I scanned it and there was a code for misfire on start up the first 1000 Rpms cylinder 5 so I replaced cyl 5 coil and the code went away the...

So I.spun two rod bearings, my motors outta my mach. Im looking to make 400rwhp maybe more. Would boring my block to a 5.0 be a good idea? Seems like making 400rwhp is almost impossible on the stock bottom end with out dumping ungodly amounts of money into. Hopefully a 5.0 would respond better...