2001 454 MAG MPI, lower manifold corroded. Options I've come up with so far:
replace with carb (requires a bunch of ignition parts swaps?)
replace with OEM part(s) from OSO/Ebay
replace with 500EFI setup (anybody done this swap? Parts interchange?)
replace with Holley EFI setup
Perhaps weld up the lower manifold if it's not too far gone. But being a salt water engine I put it far down the list.

A cam and maybe headwork are on tap for upgrades but nothing radical. Aftermarket exhaust that is Silent Choice compatible might be on the list also. Primary goal is to be running again as quick as possible.

Get a used freshwater setup off ebay or from the classifieds or swap shop.

piece of cake. mine did the same thing. go to the welder, have it tigged up for 100 bucks or less, go to the machine shop and have it faced for 100 bucks or less and you are done.

z,
Just fixed one a month or so ago. If it is just badly corroded right at the inlet to the water passage, then it is a piece of cake to weld it up and resurface it. One key to doing the job right is to get a die grinder with an aluminum bit and grind away every bit of corrosion before you weld it back up. Any performance machine shop that does cylinder head porting should be able to fix it for you. Figure in the $250 range.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

Thanks guys. Still hesitant to weld on a salt water piece though. Keeping eyes open for a replacement while deciding on a shop. Gotta do some searching for MPI mods.

is it the same as the 502 upper and lower? ive got an upper and lower off a 1999 502 mpi sitting in the garage i havent got around to listing for sale yet. PM me in interested.

arnt they all brass lined??? everyone i have seen is???