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Old 03-21-2011 | 06:46 PM
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Question SBC Carburetor Upgrade

I am thinking about upgrading from 2 barrel carbs to 4 barrel (because I want to pay more money on fuel this summer!).

I'm wondering what I can expect for HP and MPH gain. I found Edlebrock Performer intakes and 600 CFM Edlebrock carbs for just over $1K to do both engines. The 1997 (and 2008 rebuilt) stock Mercruisers probably put out about 260 HP each. Max RPM is about 4700 with top speed of 56.0 MPH (21 pitch 3-blade Lasers).

...or is it just dumb to pay more for fuel these days for minimal gain???

Thanks in advance.
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Old 03-22-2011 | 01:21 PM
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Come on experts - this can't stump you.

Any guesses?

Thanks.
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Old 03-23-2011 | 07:37 AM
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I doubt you'll see much of a gain without atleast a cam upgrade
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Old 03-23-2011 | 01:34 PM
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Originally Posted by andyt25
I doubt you'll see much of a gain without atleast a cam upgrade
Thanks for the input. That's the kind of thing I was looking for to help me decide whether to pull the trigger. You just saved me a grand and probably some frustration.
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Old 03-23-2011 | 01:57 PM
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My guess is you would gain around 30 hp per engine so you may gain 3 mph with the upgrade...
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Old 03-23-2011 | 03:15 PM
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you will see a decent gain, have done before....should see 3-5 mph, should not hurt fuel economy at cruise at all....
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Old 03-23-2011 | 03:45 PM
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We put a Qjet on a buddys 18 Sea Ray and picked up 5 MPH it ran great and that was a 4.3 V6.
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Old 03-23-2011 | 07:14 PM
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OK - SOLD!!!!

Thanks All. (I still respect you Andyt25 )
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Old 03-23-2011 | 07:46 PM
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Originally Posted by 242LS
OK - SOLD!!!!

Thanks All. (I still respect you Andyt25 )
That's ok hopefully you get some gains and the plus is when the hatch is open it'll still look better
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