fabin61

Has anybody done this or have any pros/cons doing this to these engines. I am looking at a 32' Baja that has 7.4 Merc's I would like to get up 75-80mph range. Would this do it or should I look for another boat with 500's or 454's with Chargers?

Pismo10

Cast internals, small port heads and intake. I am sure it can be done but might not last too long. Find a 454/502 Magnum or 500/525HP which all have forged internals and overall much better components which can better handle and utilize a charger..

Young Performance

Pismo hit the nail on the head. Not a good platform to start with...... 2 bolt mains, cast crank and pistons, 3/8" rods, peanut port heads, etc. You can do it however. I would not put more than about 3 or 4 pounds of boost to it. That is not going to get you where you want to be. Just doesn't seem worth the time and expense to supercharge it for such small gains. If someone called me about installing it, I would tell them that I would not do it. It is a no win situation for me. They would either get very small gains for the dollar amount or blow it up. Look for something else. The 454 Mag, 502 Mag or 500 efi or carb all have good internals. Hope this helps, Eddie.

fabin61

Eddie,

Thanks for your input. Let me ask you this then. I purchase the boat and want to swap out those engines for a pair of 500's. Would it be easy to sell those 7.4's, one has 120 hours, the other 220. Also, would any Merc dealers take those in on trade?

iboatfast

The hp500 has four bolt mains, steel crank, 7/16" rods, 8.75:1 forged pistons, rectanguler port cylinder heads, with roller rockers, HD push rods, one piece stainless intake valves and severe duty Inconel exhaust valves & a hydraulic roller cam and is very compatible with superchargers. Safe @ 5psi; The weak link are the outdrives.

Young Performance

Fabin,
You should be able to sell those engines without much hassle. As far as trading them in, I'm sure a Merc dealer would take them but they aren't going to give you much. Kind of like trading in a car at the dealership. I sold a pair for a customer a few years ago and got 3500 each. They had about 100 hrs and were in excellent shape... looked almost like new. Your biggest buyer for those will be someone with an older carb engine looking to go efi. That is who bought the pair I had. Guy had an old cruiser with 340 MIE Mercs. that were tired and he wanted efi. I would think you could sell them pretty quick if they are priced right and you'll get more money than trading them in. Hope this helps, Eddie.

fabin61

Eddie,

Appreciate your input. I am going to see the boat tonight. I even got the wife to agree that the boat doesn't have enough power and she said we could sell the engines and get new ones next year. YEAH BUDDY!!!! Michael

fabin61

Eddie,

I just checked out your site. Man, those orange blocks look awesome. I maybe calling you next Spring for a pair of those 650's

Young Performance

I have plenty of orange paint. I'm ready when you are.

Tow-N-One

Hey Eddie,

I have the same motor in my boat, and was wondering. If I rebuilt the engine, used original crank, rods with 7/16 bolts, forged pistons and maybe a little biger cam, would i be able to prop the boat for 5k RPM max? Would my HP gain be worth the effort? I'm not looking to make this boat fast, just a couple more MPH on top with reliability. The engine has over 700 hrs on it and I know the end is near!

Thanks
Charlie