I wonder if someone makes a spacer to raise the air cleaner up from the carburetor to improve air flow? ( or a 4" air cleaner)

Yes, I use a 1" spacer, for multiple reasons. 1) so my fuel line is not pinched or I could use an adapter. 2) clearance for the throttle rod, and I can't remember why else.

http://store.summitracing.com/egnsearch.asp?N=700+4294925239+4294839057+115+4294 848561

In fact SBC's with ducted hoods came new with such a spacer. What do you want a 4" cleaner for? Sounds like racen' stuff. You best behave!:D
Mine's 4".
http://epitomesrebuild.com/images/301.jpg

I run a 1" spacer below my air cleaner too. My holley tbi is very short, the spacer keeps the air cleaner off the radiator hose and the distributor.

that spacer is a good way to kill some airflow.
and, yes, there is a 14X4 element available- at least from Wix, AC Delco, and Purolator, anyways. i have one on my Ford truck and Monte Carlo right now. i don't know the application or part numbers, but it will be in the biggest box on the shelf. they even sell one with a wrap around it, which must be for some kind of HD truck application.

I run a spacer, turned it down out of a peice of Aluminuim core to a custom size to clear stuff.

what do you mean by 'improve air flow'? more air, or laminar flow, or to make a better air/fuel charge available at lower rpms? the spacer will not give more air. the air cleaner and carb inlet determines that. the shape and size of a spacer will help laminar flow for high rpms, like the high rise edlebrock rpm manifolds, rated at 1500+rpm. the benefit for that takes an increase in rpms to smooth out the airflow. for low end stuff, a smaller manifold volume (no spacer, which would increase volume) would more quickly deliver fuel to the engine and would be better. spacers, depending on the material it's made from, can add the benefit of heat isolation to the carb, cooling the intake charge. what exactly are you shooting for?

what do you mean by 'improve air flow'? what exactly are you shooting for?He's looking for a better 'shape' of the airflow into the carb, I think.

Airflow from a flat bottom cleaner has to take a turn compared to a round bowl shaped bottom. The straighter the airflow, the better the carb will perform its job.

Also, those low dished tops of custom air cleaners don't help either. They restrict the air flow into the bowl vents. Yes, the vents on a Holley style are bologna sliced, but their design is for air going into the vent pipe at a straight entry, not at an angle.

Of course, all of this airhorn design is at the carb's rated SCFM.

what do you mean by 'improve air flow'? more air, or laminar flow, or to make a better air/fuel charge available at lower rpms? the spacer will not give more air. the air cleaner and carb inlet determines that. the shape and size of a spacer will help laminar flow for high rpms, like the high rise edlebrock rpm manifolds, rated at 1500+rpm. the benefit for that takes an increase in rpms to smooth out the airflow. for low end stuff, a smaller manifold volume (no spacer, which would increase volume) would more quickly deliver fuel to the engine and would be better. spacers, depending on the material it's made from, can add the benefit of heat isolation to the carb, cooling the intake charge. what exactly are you shooting for?
i think you are talking about carb spacers- to space the carb away from the manifold.
the question was about air cleaner spacers, to get the lid of the air filter farther away from the top of the carb.
just putting a spacer in there will kill air flow. but if you run a taller filter, then that moves the lid up away from the top of the carb. he was asking about improving airflow into the carb by doing that.
i don't know if there is much power to be found from doing that, but i think the air cleaner lids with a "dome" shape help airflow compared to a flat lid, but i kind of think that effect would be canceled out by putting the lid too far above the carb.
i only run the taller filter element because i think a 3" element just looks goofy, and the 4" element looks "tougher".
on my Nova, i did some testing on an 1/8th mile track during a "street" night, and i didn't see any difference between a stock mid 70's snorkel air cleaner, a 14X3 element in my GM drop base air cleaner, and the 14X4 element in the same lid and base.. but i did pick up a teeny tiny little bit (like 1/100 second and 1/2 mph on a car that got crappy traction off the line and got shifted slightly different by me on every run) using my home made dual snorkel ram air setup. granted, this was a very unscientific test, but i just wanted to see if there was any real difference and didn't notice any.
start talking fuel mileage, tho, and the dual snorkel ram air setup spanked everything else.

doh! good catch, nova!

You guys all make me jealous. I wish I had a -1" spacer so I had more hood clearance :D