Carbs

[misspentyouth]

I have an open vacuum intake tube on the right side of the carb. I don't know if I should cut it off, or if it goes somewhere I cannot tell.  Also, how difficult would it be to put a 4-barrel carb on the l18 motor. And, if so, what model of carb would you use? any help would be appreciated.

 

[datzenmike]

First of all a larger carb does not always make more power. If it did we would all be running dual 4bbls. It doesn't work that way. An L18 revved to 7K will move 222.39 cubic feet of air. So if you throw on a 500 CFM (cubic feet /minute) holly 4 bbl you have 227 CFM left over not being used. It's unlikely there would be enough air drawn in to pull the back two barrels open. And this is at 7,000 RPMs!!!!!

 

I think there is a 300 CFM holly 4bbl, not sure, but you would still have to buy or make a manifold for it. Still a  bit big.

 

The 32/36 2bbl Weber is rated at 270 CFM. Plenty big enough and then some. It also fits the L16/18 manifold with an adapter plate.

 

Never, never, never, never, never... over carb your motor.

 

 

That is likely the vacuum advance for the distributor. A picture.. A clear picture would help.