Great Lakes 4x4. The largest offroad forum in the Midwest banner

1 - 6 of 6 Posts

·
Merkin salesman
Joined
·
1,255 Posts
Discussion Starter · #1 ·
Ive finally figured out the problem ive been having with my boat. Its got a 3.0 4cyl GM motor and a 2bbl rochester carb, but the carb ive traced to be used on a 77 chevy 305 V8. So, how many CFM should I get for the new carb?? Ive heard a lot of good stuff about the holley 500, but I know there are people here that know a lot more than I do. I am however 100% sure that its the carb, so please dont debate on that. Thanks a ton
 

·
Premium Member
Joined
·
5,445 Posts
I think what you are saying is that the carb on your boat belongs to a 305, so it's not original to the 4 cyl on your boat.

We had a 86 bayliner that had the same engine. It ran good and had decent nuts for a big 4 cylinder. I have no idea what carb was on it, but being a 4 cyl, I"m sure it was some sort of 2 bbl. carb.

Being the holley is a 2bbl and is common to v6's, I can't see how it would hurt being the displacement of the 4 banger merc is similar to most smaller v6 engines. If it bolts up, I can't see any reason not to go with it.
 

·
Merkin salesman
Joined
·
1,255 Posts
Discussion Starter · #3 ·
Rite matty, this is not the origional carb for the boat and ive been having troubles finding one to fit for a good price. These came stock with 2bbl rochester and mercarb's, but this one is way too big and has a large bolt pattern. So, rather than replacing the intake/exhaust for a smaller bolt pattern, I figure that i will just find one that is better suited for my 4cyl.
 

·
Registered
Joined
·
1,789 Posts
i got a boat sitting at my shop with the 3.0L GM mercruiser engine. the block cracked because the owner didn't winterize it. i can try to take some pics and post numbers either tomorrow or on monday if you want.

since the block is cracked i'm playing with the idea of putting a GM V6 or V8 in. the bellhousing bolt pattern is the same. and i just so happen to have a 350 that i just got for free from a buddy of mine.
 
1 - 6 of 6 Posts
Top