carburetor opinions.

henleyhale

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On my 305 sits a carter quatro, it works fine, yesterday my old man was on the water with me and we were having some timing issues, he looked at the carb and started carrying on about how he wouldnt have one of those on a childs tricycle ,he's a funny guy, he believes it is less fuel efficient than a holly 4bbl, and its a pain to adjust, now i agree it is a pain, because access to one of the adjustments means threading a flex head screw driver through the water hoses. So weigh in with your favorite, fuel economy to me is more important than added power, I am not looking to race just cruise around 3800 rpm
 

gm280

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Henley, if all you're interested in is fuel economy there are a lot of single barrel carbs to supply that. But somehow I get the feeling you want power with fuel economy... That IS a different animal... If true economy with power is your goal, look into fuel injection. Better cranking and lots better fuel economy with power. Less waste to achieve those goals. That IS what I would do if those goals were mine... JMHO!
 

henleyhale

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Wowza! Fuel injection conversion kits are speeennnddyyyyy :) how much would performance suffer with one of those single or double barrell jobs? And would i need a new intake manifold for a single or double?
 

gm280

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Wowza! Fuel injection conversion kits are speeennnddyyyyy :) how much would performance suffer with one of those single or double barrell jobs? And would i need a new intake manifold for a single or double?

Of course fuel injection is the more costly way to go, but the pros are equally great too... Any two barrel carb (nice Holley for instance) will work with your present intake manifold providing you install an adapter plate for it. Shouldn't need anything else. Of course you will have to adapt the throttle cables to it, but that is not hard to do at all... But even a two barrel will use a lot of gas if you run it towards the top speeds. And going from a four barrel to a two barrel will certainly take some top RPMs off your speed as well. Again, just my opinion...
 

Fishermark

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My opinion? Leave what you have on there alone. I'm a little confused as to what you currently have. Are you saying it is a four barrel Carter carburetor? Or by Quattro do you mean Quadra jet? Everyone has an opinion on carburetor brands. They all work well if clean and adjusted properly.
 
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duped

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x2 on leaving it alone. Whether you have a Weber or a Q-Jet, both are good, relatively efficient carbs. I'm not convinced downgrading to a 2 barrel would save any fuel at all in a marine application, and even if it did, it would take a LOT of running to make your new carb's investment back in fuel savings. Especially when there's nothing wrong with the current carb.
 

NHGuy

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Yeah Carter did produce quadrajets, and when they are right they are great. Holly fans like what they understand and know, that's all.
If you do decide to get a carburetor make sure it has the marine provision for the fuel pump fail indicator tube. That's a vacuum port on the carb that gets connected to the tygon tube from the fuel pump. if the pump diaphragm fails it fills with fuel instead of dropping the fuel in the bilge where it's a safety hazard.
I'd say use the one you have too. If you want to easily adjust the idle mix on the front of the qjet go to the auto parts store or online and get one of those bendy spring carb tools that have 4 tips. Makes it easy. Plus since your dad already understands this stuff it will be 2nd nature to him.
BTW if you don't hammer the throttle it's like having a much smaller carb. A 305 can barely pull open the secondaries on that big carb. They only open when there's a wide open throttle AND there's a lot of air flowing into the engine. Probably above 3400 rpm with WOT.
 
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henleyhale

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Thanks for everyones input :) ill leave it alone, and ill get the springy adjustment tool. I rarely cruise over 3500 rpm anyways. Only to make sure she runs right really. Thanks for all your opinions!
 

Bondo

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Ayuh,.... I've always been a fan of the Carter AFB carb clones,... Merc/ Weber, 'n Edelbrocks Performer series,...

Ain't been into a Quadrajet in many years,....

I see the fore/ aft bowls of the Holley as it's downfall on boat motors,...

Side to side bowls tune to the til of the hull easier, I believe,....
 

Maclin

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I have never heard Holleys described as more fuel efficient than ANYTHING, lol...
 

Scott Danforth

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the only fuel efficient boats have oars or sails. neither a Holley (my preference) or a Carter Clone will be efficient. EFI is as efficient as you can get on a boat, however it is running open loop speed density and simply dumping fuel on top of the pistons to keep them cool and to ward off detonation.

Unlike a car, where the motor is barely loaded as you are "cruisin", a boat motor is always loaded. think of a truck with a 2-yard load of gravel driving up an incline while driving in sand. that kind of load requires fuel.
 

henleyhale

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Ya know i started this thread just to hear yall banter on, but now i got my new distributor in stabbed it replaced all plug and wires fired her up and before i could grab my light fuel started coming out of my carburetor..... who can give me a smiley with the guy beating the other fella over the head with a fish? So looks like ill be the one getting into that carter quadrajet. The oldman doesnt know the thing well so its by the book for me.
 

WIMUSKY

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:fish: There ya go! Yep, x whatever on the q-jet. Great carb....... Just ease up on the go handle if you want a little economy...... :)
 

henleyhale

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Why would anyone want to fix something that ain't broke???
in boating there is maintenance and there is preventative care, same reason you replace your impeller every season, it aint broke yet but its on its way out, the better you are at catching it before it occurs the happier the admiral is when your on the water, you want a ticked off woman.... go on ahead and just let it all break on ya when your in the middle of a big lake around 10 p.m. but werent planning on staying the night. When my family is aboard my vessel i cannot have a good time if im worried about what if i shoulda done this or that last week, all i think about is maybe not too far from the dock, eh. My boats are always old so i rely on my wrenches and keep a keen eye out for anything not ticking just right, and if i spot it, i head home and get her fixed before im dead in the water holding an airhorn and a rope.
 

H20Rat

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in boating there is maintenance and there is preventative care, same reason you replace your impeller every season, it aint broke yet but its on its way out,

I'm with the previous posters, why replace it. An impeller is a wear item. Do you replace your deck cleats on a schedule, or how about a perfectly good depth finder? Or the throttle/shifter cable, even if it shows zero signs of tightening up?

Carbs aren't wear items, they don't generally wear out, ever. As long as you are running decent gas and running enough of it through, it won't plug up. There is no reason to preemptively replace it. And if you still feel the need, go fuel injection.
 
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