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  #1  
Old 06-03-2007, 10:59 PM
ucf_motorcycle ucf_motorcycle is offline
 
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2bbl to 4bbl carb conversion

I have a 96 302 Ford with a Volvo Penta SX outdrive. The engine has a 2bbl carb on it and its in a 23' Wellcraft Excel SE cabin Cruiser.

With this setup the boat takes a very long time to plane. I want to get a little extra power out of it and was thinking a 4bbl carb might do the trick.

What all would I need to do this conversion and how much would it cost me?
What kind of power gains could be expected?

Is there anything else I could do to get more power out of it. I don't really want to just change props because I still like the tp speed i'm getting just want to get there faster.
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Old 06-04-2007, 12:18 AM
stonebreaker stonebreaker is offline
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The 4 barrel is going to help top end, not midrange so much, so it's not going to help your planing speed. Better plan might be to add the 4 barrel carb, maybe some stronger valve springs, and swap the prop for one with a smaller pitch; and make up the difference in top speed by revving the engine higher.
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Old 06-04-2007, 01:12 AM
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StianM StianM is offline
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If you want to do a investment in fuel system buy a injection system.
A injection system is easy programed to give fuel where you nead the fuel so you can get a higher power in the mid range without compromising top end.

Call a cam manufacturer and tell what engine you have, operational RPM and what you want from your engine and have a cam suited for your neads shiped to you.

Playing with carbs won't really get you annywhere. You can trow on a smaler one geting bether response in the mid rpm, but loss the top end. You can trow on a biger one geting more top end, but lossing the mid rpm.
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Old 06-04-2007, 01:19 AM
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Frosty Frosty is offline
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Fit an Edelbrock intake manifold or similar for a four wheel drive application.

You need torque,-- put on your 4 barrel. ( I would go for mechanical secondaries).
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Old 06-08-2007, 12:02 PM
ucf_motorcycle ucf_motorcycle is offline
 
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Will there be a problem fitting an aluminum automotive intake manifold on my marine engine with regards to saltwater corrosion?
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Old 06-08-2007, 12:09 PM
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Quote:
Originally Posted by ucf_motorcycle View Post
Will there be a problem fitting an aluminum automotive intake manifold on my marine engine with regards to saltwater corrosion?
No...
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Old 06-08-2007, 12:33 PM
stonebreaker stonebreaker is offline
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Quote:
Originally Posted by Frosty View Post
Fit an Edelbrock intake manifold or similar for a four wheel drive application.

You need torque,-- put on your 4 barrel. ( I would go for mechanical secondaries).
I would think the stock manifold is already a dual plane, although since he's going to need a new one for the four barrel anyway it doesn't hurt to look. But the 302 is a short stroke motor - it was originally designed for Trans-Am racing back in the 60's. It's going to respond better to higher rpm than trying to get more torque out of it at midrange.
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