Are tanks always 6in in diameter?

[dhuynh]

Regardless of tank capacity, it seems like all the tanks I've seen for sale are always 6 inches in diameter. I have a perfect spot in my trunk that's 5 inches deep. If I could find a 3 gallon that's slightly longer and has a diameter of 5in would be perfect. I've seen a few companies selling some that are very long though such as this one

http://www.openroadtuning.com/2-gallon-aluminum-slim-tank/

But it's too long to work. Any other options in tank size? It seems most trunk set ups always have a part protruding from the trunk floor. Seems like most people would want a tank that's an inch smaller and a few inches longer for a complete stealth setup. No more false/raised floor mods.

[Alex@BagRiders]

No not every tank is 6" in diameter but that is one of the smaller sizes for tanks that are 3+ gallons. What type of car do you have?

[KyleAnderson]

The greatest increase in volume comes from increasing the diameter.

Example, a 3 gallon tank:
6" diameter, 24" long
5" diameter, 35" long

1 inch smaller diameter means you have to add 11 inches to the length. Most people would rather give up 1 inch than 11.

This 4" diameter 1 gallon tank:

http://www.airbagit.com/Air-Tanks-p/airtank-1gal.htm

Maybe use 2 of those, if your space allows it? Similar to my setup, which uses two 1 gallon tanks (6" diameter).