Mercruiser 7.4 liter replacement options..HELP !!!

[ski65nut]

I just blew my 1996 7.4 liter MPI/ 330hp and am looking for guidance. My mechanic told me I can buy a long block 7.4 liter or replace it with a brand new 383/ 350HP drop in. the 7.4 is a big block and the 383 is a small block and 150 ibs lighter.
Would anyone know what is recommended or have another suggestion?

Thanks for any and all help !!! This won't be cheap and I want to make the right decision

Paul

 

[onsiteservice]

Re: Mercruiser 7.4 liter replacement options..HELP !!!

There is no replacement for displacement! Meaning depending on what you do with your boat and how much you want to spend the big block will normally outperform the small block on the low end and mid range. Even with the 20 HP more the boat will not come out of the water like the big block did, not to mention you'll probably have to re-prop. One of the experts might be able to provide you with better info than I but I would think that exhaust manifolds, as well as a lot of other little things that will add up quick would need to be replaced.

Why is he trying to talk you into a 383? I wouldn't think there would be that much of a cost difference, unless he wants your engine? But then again I would think you would have to provide a core (usually has to be same for same) and those are not cheap either in my experience.

Goodluck, but my opinoin you wouldn't be happy with it going from the big block to the small block.

 

[92rslt1]

Re: Mercruiser 7.4 liter replacement options..HELP !!!

Big blocks are easy to get power out of. I would never ditch a bbc for a small Block. Just get a set of 088 heads a Cam and the proper intake carb combo to match.