Carb question

[63longfleet]

Thanks in advance for any input on this. I am pulling the motor from a 1985 Boat to put in my truck, I am changing the cam to get something streetable, as far as ive been told i have to change the carb out too but no one can tell me why, just that it wont work in a truck/car. The carb on the boat is a quadrajet which i like just wondering why it wont work on a truck.
Charles

[WOLFMANmike]

ok so i havent had to deal with boats ever lol but as far as i know the boats that have V8 automobile engines in them can swap right into a car or truck and vice versa .. so that being said as far as i know . i would think that regular fuel is fuel and that the carb would run it no mater what its in ... here is 1 thing tho to consider . a Q Jet carb can be a good carb but the very moment the slightest little thing happens to it . it becomes a BIG piece of junk wont run right sputtering all kinds of crap .. but a good eddlebrock or a holley and they will both take a hell of a beating before things go hell west and crooked on you. you may want to hear from some others on here about the swap . but as far as i know gas is gas and it should run the same no matter what its in ..
Happy Truckin

[geezer#99]

Quadrajet will work.
Intake might not!
Normal intake is not level on the carb flange. Usually about 3 degrees off level.
Boat intakes are even more off level. Up to 10 degrees IIRC. Or more.
And the distributor might need recurving.

[Steve66]

Quadrajets are really good carburetors. They aren't the easiest thing for a novice to work on and it takes some talent to get one jetted and tuned right with all the combinations possible but once they are they will run for years and years with no attention. That's what all the GM vehicles from about 68 until sometime in the late 80's used until they were replaced with fuel injection. The thing about a quad is that the same carburetor can be tuned to run on a v-6 all the way up to a slobbering big block. Small primaries give you decent fuel mileage and big secondaries give you all the gas you can handle. As far a boat carburetors being different I have no idea why they would be. Also I would prefer a Holley over an Edelbrock.

[Jurassic-1]

As far as I know a boat Quadra Jet is the same. On a boat the air cleaner is a closed system so it will not catch fire from vapors in the engine compartment. I think the carb is the same as a car.

['63GENIII]

I would try running it just the way it is. Cam and all. See how it does. I'm sure that the carb was tuned to run with that cam and unless it was a "hot boat" engine, I would think it may do fine for you. Geezer and Jurrassic bring up very valid points in that the angle of the carb flange may be different depending on whether the boat was a v drive, inboard or I/O. The factory boat ignitions and starters are sealed to prevent exposed sparks in the engine compartment and the carbs usually have the bowl vents dumped back into the carb to prevent bouncing the fuel out of the spark arrestor while on the water. I've had very good success putting boat engines into trucks in the past.

[GRX]

To state the obvious. Be sure that engine is not reverse rotation. Marine carbs are usually tuned for different torque curve than auto carbs. They are also plumbed differently so the atmosphieric vent is turned down into the carb throat. This is so if it floods the fuel & vapors will be sucked into the engine and burn, not go into the bilge of the boat where fumes can build up. Therefore using an automotive carb on a boat can be dangerous, well as illegal. Should not be too much problem going the other way except for tuning as mentioned above.

[prostreetC-10]

At least with a Holley, the metering of fuel is different. The part or cruise throttle on a boat is very different than a car. Tire rolling resistance VS a boat pushing water is a huge difference. This affects throttle blade position and the trans circuit from idle to the boosters. With that said, guys get away with using marine carbs on the street all the time and street carbs on boats. It is ideal? No but only trial will tell you. At least the J hooks on a Holley cause a stuck float to drown your motor rather than your intake and the exterior of the motor which can equal a fire.

[crazy longhorn]

Pro street....good to see you in the forum again ...Longhorn

[cableguy0]

Originally Posted by crazy longhorn

Pro street....good to see you in the forum again ...Longhorn

Seconded. Welcome back buddy.

[Captainfab]

X3....good to see you back. Don't be such a stranger

Originally Posted by cableguy0

Seconded. Welcome back buddy.

[prostreetC-10]

Man thanks guys......I really appreciate that!