Difference in years 305 motor?

[joetheis]

Looking on Ebay at Mercruiser 305 motors, (mine is good, but you know)............
Many state for example 95 and newer.
The ones I looked at have 4 bbl Rochester style carbs, (like my 1980)
I understand the 1 piece rear seal, mine MUST be a 2 piece
Also "standard rotation"???
Looking at the motor which way is "Standard rotation"?
I THOUGHT a small block Chevy motor (Mercruiser) we all the same blocks?
Is it have to do with the crank for the coupler?
Joe
Why do they have to make this complicated????

 

[jkust]

96 and newer would have Vortec Heads IIRC.

 

[Bondo]

Looking on Ebay at Mercruiser 305 motors, (mine is good, but you know)............
Many state for example 95 and newer.
The ones I looked at have 4 bbl Rochester style carbs, (like my 1980)
I understand the 1 piece rear seal, mine MUST be a 2 piece
Also "standard rotation"???
Looking at the motor which way is "Standard rotation"?
I THOUGHT a small block Chevy motor (Mercruiser) we all the same blocks?
Is it have to do with the crank for the coupler?
Joe
Why do they have to make this complicated????

Ayuh,.... Welcome Aboard,....... Yer 1980 is a 2 piece main seal motor, they went to 1 pc. in '86,.....

The Vortec heads came out in '96,....

Somewhere in-between, they stopped drillin' the fuel pump boss for mechanical fuel pumps, 'n though the bosses were in the block castin' since '86, the roller cams came along at different times for different applications,...

All these changes are Chevy based, Merc followed along, adaptin' the GM's changes,......
'n Standard rotation is a lefthanded motor, as viewed from the Pto end,.... clockwise at the pulleys,...

 

[midcarolina]

Keep an open mind and also consider a 350......... IMO the 350 is the better way to go, same block just different bore and stroke I think all would agree a 350 is by far a superior motor.

 

[Bondo]

Keep an open mind and also consider a 350......... IMO the 350 is the better way to go, same block just different bore and stroke I think all would agree a 350 is by far a superior motor.

Ayuh,.... 'n All the same changes at the same times,.... All the bolt holes line up,.....

While the 350 is far Better than a 305, if yer goin' new/ reman, the 383 is as far Superior to the 350, as the 350 is to the 305,.....

 

[midcarolina]

touche', toshey, too.............. well you know what I mean............:lol:

 

[joetheis]

My first thoughts were "GO BIGGER" 350!
But I read somewhere on the internet, (and you know it HAS to be true, I saw it on the internet), a 350 crank bolt holes are bigger radius????? (sounds fishy)
Then I thought, "I know a guy who has a 327 block, 4 bolt mains, steel crank, with a set of 2.02 "fuelie" heads that would look nice in my boat!
Swap the cam, the intake and poof!
I'm gonna run a compression test on it when I get her home, (it looks like a fresh motor, so I'm thinkin it'll be OK).
I do have to yank it to replace the steel EXPANSION plugs in back, so.....................
Joe
That's my biggest problem.......... It's running PERFECT! Let's mess with it and see what happens!

 

[Fishermark]

A 327 typically makes it power in the upper ranges of the rpm scale - not what you want in a boat. Can you change the cam, etc? Sure, but you still will not have an engine as good as a 350 - or, as Bond-o suggests, a stroked 383. In fact - the 350 is basically a stroked 327. They all have the same 4" bore.

 

[Bondo]

A 327 typically makes it power in the upper ranges of the rpm scale - not what you want in a boat. Can you change the cam, etc? Sure, but you still will not have an engine as good as a 350 - or, as Bond-o suggests, a stroked 383. In fact - the 350 is basically a stroked 327. They all have the same 4" bore.

Ayuh,.... I was gonna mention that, that 327 don't sound like it's "Built" to be a Boat motor,.....

The '68/ '69 302, the 327, 'n the 350 share the Same block,.....
A 3" stroke from the 283, for the 302,.....
The 3.25" stroke for the 327,.....
The 3.48" stroke for the 350,....
'n if ya cut down a 400 crank, ya get the 3.75" stroke for the 377/ 383,...

The internet comments 'bout the 350 havin' different bolt holes, relates to the rear main seal change, Not 305 Vs:350,....