85 GM 57 inboard marine motor

"First Off I appreciate all yo

"First Off I appreciate all you guys help!!
I am looking at a 85 GM 5.7 rebuilt engine that is complete and was a inboard motor. I am replacing a 94 mercruiser 5.0 LX Alpha 1. The outdrive is OK and is a Alpha 1 gen 2, Should be OK to run with the 5.7
It looks like different flywheel housing then I need? Will the flywheel assmy from the 94 bolt on to the 85 OK?
Will my electrical from my 94 bolt up on this OK?
Should I change the intake,carb ,and distribitor?
The 5.7 has electronic ignition already but would the thunderbolt ignition be better?
What things could be a problem switching from the 94 5.0 to the 85 5.7?
What do I need to absolutely need to change to make this work?
All responses welcome"

"First you must verify that th

"First you must verify that the 94 inboard engine is the correct rotation. If the inboard engine is a Mercruiser then the wiring on it should be ok. Does the starter for the inboard engine mount in the same place as your I/O or mount from behind the bellhousing? If it mounts the same as th I/O then the bellhousing will need to be changed and the coupler. Here is the rub, the 85 engine uses a 2 piece rear main seal and the 94 a 1 piece. the couplers are different. You will need the triangle coupler from an 87 or later merc or the adapter style coupler from mercruiser. If the manifold and risers are the same all should be well to change. leave the ignition and fuel system alone on the 94. The drive ratio is the same for both. Good luck and have fun. You should notice a dramatic change in the boats performance."

"Thanks, But I am talking abou

"Thanks, But I am talking about replacing the 1994 5.0 Mercrusier I/O and putting in the 1985 GM 5.7, That was a inboard and making it into a I/O and having the 85 fit on the Alpha 1 outdrive."

"IF the flywheel will bolt up,

"IF the flywheel will bolt up, you should be okay. Use all of hte other marine stuff, and replace the freeze out plugs with brass ones. The prop will need a bit more pitch, but you'll be pleased with the performance!

Jeff"