305 Mercruiser Vortec Heads ?

Davidsgara

Seaman
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Jan 25, 2019
Messages
60
Can anyone tell me if my 305 would have Vortec Heads? Engine No 0W012412.
I was looking into getting a Edelbrock manifold and 4 barrel carburetor and wanted to know if Edelbrock performer manifold part # 2516 would suit my Engine?
Also thoughts on Edelbrock # 1409 - 600 CFM carburetor with this manifold combination would give me much more power than my standard mercarb 2 barrel carburetor?
Thanks
 

Bondo

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Ayuh,...... Look at where the intake, meets the heads,.....

If there are 12 bolts, 6 to a side,...... Their Not Vortec,......
If there are 8 bolts, 4 to a side, with none in the center area,.... Those are Vortec heads,.....

The 1409 is a carbon copy of the Merc/ Weber carb, that Merc has been usin' since the early '90s,.....

You'll get about 20 hp increase, mostly at top-end, but improved acceleration throughout the rpm band,....
 

Davidsgara

Seaman
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Jan 25, 2019
Messages
60
Thanks Bondo 👍🏼

I will get to the boat tomorrow and have a look.

Its a 2004 model so I’m thinking it should have Vortec heads ? Also from memory the rocker cover has bolts along a line in the center I think that is also a Vortec thing?
 

Scott06

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Apr 20, 2014
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5,542
Yours should be a vortec as bondo stayed look for 8 vertical intake bolts vs 12.

I have the same boat as you. I replaced the 4.3 that the previous owner cracked with a 5.0. I had real good results with the 1409 on it. Real good throttle response. I did end up going one notch ritcher on the primary metering rods (.65 x .42) and using the .043” accelerator pump nozzle to cure and off idle stumble.

You will Need Merc part number 805359T throttle bracket as your original has different bolt spacing for the Mercarb. Your throttle cable, slave solenoid, and 12v circut breaker will bolt up to this bracket same as on your mercarb bracket for a clean factory installation.

You will also need a different flame arrestor to fit the bigger carb, and the fuel line will likely need to be modified or replaced as I think the fuel comes in the front of the mercarb vs left hand rear on the edelbrock. There are some aftermarket marine premade fuel hoses of various lengths available or you can use 3/8 preflared brakeline from any auto parts store if needed.

On a separate note what wakeboard tower tower do you have and did the original Bimini fit under it ?
 
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Davidsgara

Seaman
Joined
Jan 25, 2019
Messages
60
Hi Scott

Yes you were right I just checked and confirmed it does have Vortec Heads.

Thanks for the info on the throttle bracket I will order one today.

Also thanks for the feedback on the 1409 metering rods and accelerator pump changes as this will be sure to save me some time in tuning.

I only bought the boat a few months ago with very low hours (130) from a guy who imported it from the US (As I’m in Sydney Australia) and it has had very little use.

The Bimini does fit under the sports tower and I think it’s all original specs. The sports tower still has a part number sticker on it (200 sport 1759642) written on it.

Any chance you could post a picture of your fuel line set-up?

Thanks
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Just looking through parts drawings... You have an electric fuel pump. It looks like all the 4bbl SBC (305 and 350) engines were a mechanical pump, so a new line from the electric pump to a 4bbl carb will need to be a custom fabrication. May I suggest you get it made in stainless steel. ;)

Chris.....
 

Davidsgara

Seaman
Joined
Jan 25, 2019
Messages
60
Hi Chris

Yes it’s does have an electric fuel pump but only a 2 barrel mercarb.

I was thinking of getting a hose doctor (Pirtek or Enzed) to make up the fuel line? In marine grade fuel line with swage fittings. What do you think?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Hi Chris

Yes it’s does have an electric fuel pump but only a 2 barrel mercarb.

I was thinking of getting a hose doctor (Pirtek or Enzed) to make up the fuel line? In marine grade fuel line with swage fittings. What do you think?

That's what I'd do. (How's the drive trolley coming along?)

Chris.......
 

Davidsgara

Seaman
Joined
Jan 25, 2019
Messages
60
I ended up just getting using my engine stand and made up a bracket to suit.

As my boat is stored on a boat ramp it was too difficult to make up your style lift and make it work on a slope even though I appreciate you taking the time to measure up for me.

Also ended up getting a gasket for my distributor told the local merc guy what you said and he ordered it straight away.

I’m really happy to be part of this forum as I would really struggle without the experience of all you guys.

Im sure I will have plenty of questions to ask in the future.😊
 

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Bondo

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Ayuh,...... Unless an aluminum intake has bronze lined water passages, it should Not be used in saltwater,......
 

Davidsgara

Seaman
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Jan 25, 2019
Messages
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I believe that the Edelbrock 2516 marine intake manifold has bronze water passages ?
 

Davidsgara

Seaman
Joined
Jan 25, 2019
Messages
60
I have now ordered the Edelbrock Carby and manifold and wanted to know if I should use specific intake manifold gaskets? Marine ?? Its an electric choke version. How should it be wired up ? Do I just use the original wires ?
Any tips on removing and re-installing the dizzy ?
Thanks
 

tank1949

Lieutenant Commander
Joined
Apr 4, 2013
Messages
1,759
Can anyone tell me if my 305 would have Vortec Heads? Engine No 0W012412.
I was looking into getting a Edelbrock manifold and 4 barrel carburetor and wanted to know if Edelbrock performer manifold part # 2516 would suit my Engine?
Also thoughts on Edelbrock # 1409 - 600 CFM carburetor with this manifold combination would give me much more power than my standard mercarb 2 barrel carburetor?
Thanks

Make sure that u have the clearance between top of air breather (with high rise manifold added) and hatch.
 

Scott06

Vice Admiral
Joined
Apr 20, 2014
Messages
5,542
Fuel pro makes good intake gaskets. For the choke take the 12v+ connection off the old carb choke and it will hook up to the new choke. I think the edelbrock requires a ground wire, use the supplied pigtail to ground to engine, plenty of bolts in that area to ground with
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
11,798
The Fel Pro intake gaskets are very good. Make sure to check the torque setting for the bolts, I think its a good deal less than the 30 ft lbs for the non vortec versions like mine. Re-installing the distributor can be tricky. Make sure that before you remove it, you have the engine set so that the distributor rotor is pointing at number 1 plug terminal in the cap (mark this on the outside of the distributor body) and the timing mark on the harmonic balancer is lined up with the tab on the timing cover. This will make it easier to re-install it properly. You can also mark the position of the bottom part of the distributor body on the old intake and make a similar mark on the new intake. Helps to get it right...
 
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