I have a stock 351M.
I found pitting on the machined surface of my iron intake manifold that was causing leaks. Just prior to that I rebuilt the Motorcraft 2150.

I can't justify spending a bunch of money on a new 4 bbl carb right now but I think I might want one in the future.

Do I replace the manifold with an aluminum 4bbl manifold? If I go that route I would have to find an adapter to fit the 2bbl on it which doesn't seem ideal. Does such an adapter even exist? I sure as heck can't find one. And if I have to spend $100+ for an adapter, it kind of ruins the attempt to save money.

Do I try to get my heavy iron manifold machined so I have a nice surface again and reuse it? This seems like it may be the best option...

Please voice your opinions/concerns/warnings.

 

JB Weld and a new gasket? Cheapest option for sure.

Craigs List or eBay for used stuff. I picked up a used Edelbrock Performer 400 locally for $60, and my 680 CFM Holley for $200 I think. Avoid an Edelbrock SP2P as it would probably be worse than the factory intake.

 

Mrgasket makes an adapter that will take a 2 barrel to a 4intake or a 4b carb to a 2b intake. Ive used them before and worked just fine but it will raise your carb about 1 to1.5 in. I have also taken and plugged the intake holes,removed the carb studs and with a floppy disc grinder resurfaced that base before with no issues, just take your time.

 

If a 400 manifold will work, I still have a 2bbl one sitting around. You can have it if you'll pay to ship that heavy sucker.

 

Thanks for the offer, but I think the shipping would take a large chunk of what I could put towards a new 4bbl manifold.

I'm going to give that flapper disk resurfacing a try when I get a chance. Thanks everyone for your thoughts.

 

You'd be better off with a flat file than a disk grinder.

Are you running the EGR plate? That seems to be the EGR supply and passage running into the intake. JB Weld might work, although it might get too hot. Try it and see how it works. If it smokes, it's too hot. If not, you're home free.

I suppose you could drill and tap the holes and use threaded plugs, although that might increase chances of knocking if you are using the EGR now.

R.

 

Definetly file instead of flap wheel, just make sure you draw file it across all different directions to keep it nice and flat.

Easiest would just be to clean the void up with a grit blast and use Devcon aluminium epoxy putty to fill then flush off, that'll handle the heat.

 

The egr plate was there, but you will notice in the picture that the passage has been blocked off. If I can successfully get this thing resurfaced, I'm probably going to replace the plate with one of these:


It's Felpro # 60529. It says it won't fit my 77 351, but I think that is because it's not stock. I think it will fit. Online listings show compatibility with early 80's 5.8 engines. The MC2150 carb was used at least until 85 as far as I can tell. Correct me if I'm wrong.