ok this is just an oppion! but i have owned but and liked neither! holley is the way to go.but out of the 2 ed carb is better than the other!

What model/type Holley.....

well gt is correct! about when they run well they do really great... but when they fail its alot of money to get them rebuilt . cause anyone can rebuild a carb but quadrajets are really touchy!!! and if there not perfect it wont work right at all! if i was going to put a holley on my 350 a 600 is all you need.the model is a 4160.

If I bought a rebuilt Quadrajet, how much does the model number matter?

Stay with your original Q jet, find a tech. with experience rebuilding it. Check with your local independent repair shops. I used to bench build those for around 250.00 with kit and float. They are not hard to kit if you know what you are doing. do not buy a rebuilt.

How do I know if it is worn out? What is the difference between buying a rebuilt and having mine rebuilt? I submitted a picture before referring to cable hook up, someone said it looked like a car carb, not marine.
 Pics not loading, will try again.

here they are

OK, just throwing this at you, don't take any offense, not my intention...

Get a vacuum advance lock out kit and throw away the vacuum pot on the distributor. Buy either a Quick fuel 650 CFM mechanical secondary four barrel Like this   http://www.quickfueltechnology.com/carburetors-ss-series/street-carburetor-650-cfm-annular-booster.html


You will need to buy a carburetor adapter to get from the spread bore to a square bore, then probably have to jet it.

My reasoning is this....Someone just threw an automotive motor in your boat.......

Depending on what year the engine is, I would also consider advancing the Cam timing about 2* and run the timing pretty hot (like in the neighborhood of 36*BTDC)...

It will wake it right up....

You "could" get it to work, but you will struggle with that automotive Q-jet. It was my assumption that this was a marine OEM dealio....My bad.

GT

The number off the body is  7045583.......Trying to start motor after complete strip/rebuild of boat. Trying to see if the motor will siphon from a gas jug, no luck. Shouldn't the mechanical pump be pulling fuel through the line or might the jug be too high (sitting on the floor, 8+ inches higher than the pickup in the tank). Just trying to aviod putting a lot of fuel in the tank for know knows how long.

Thanks,
 you guys have lots of good knowledge!