our honda n600 has a 6 gallon tank, and I don't see a problem with filling up every 3-4 weeks, I don't think there is alot of extra space under there from what I remember, but I supose you could get another gallon or so in, but if you really want to boost it, get a gas can and fill it up at the same time as you fill your tank, and make sure to use the whole thing befor you fill up again.

I think you should be able to, I know with CRXs you can swap the tanks around.

That said, how much gas are you using every fill up? What's your gas mileage like? If you improve your mileage you'll get the same result, ;)

Darn, I have a '93 vx :(. Thanks for the info. A mechanic told me the thanks from the dx won't fit (but who knows, it's not like he tried the swap).

And for those who are asking me why I want to do it? I drive over 100miles/day. I have to fill it every four days.
Gary

Well, I'm trying to determine if you're being sarcastic, but there is no way you're gonna fit five gallons in there.

I filled up exactly 10 gallons once so I'm sure there is half a gallon extra (.5 gallon - perhaps that's what you mean).

Gary

I'm using about 9.5 gallons at every fillup. I'm getting about 48mpg (best of 52mpg). I have a CA vx.

I'm doing a 100+ mile commute/day.
Gary

Gee I must have a confused 94 CX cause my car has on numerous occasions taken well over 10 gallons even over 11 gallons so For my car I would say 11.9 gallons FACT. So for VX's and CX's all having 10 gallon tanks, I don't think so. Infact I drove 7 miles sputtering runnin outta gas to a station and filled it up with 11.6 ish gallons.
So take it for what its worth on the 10 gallon tank subject, some might but some(ONE) definitely DON'T.....
Try drivin past E but watch the gauge as long as the needle moves around you got fuel in the tank when the needle stops movin all together go fillup.
Well that's how my gauge works atleast.
Check my gaslog for gallons used.......

Their used to be companies which made auxiliary fuel tanks which went in the hole that the spare tire normally went into. If you went that route, you could probably get 50% additional fuel capacity.

I tried looking for one of those aux tanks a few years back but couldn't find one for our cars. Maybe I should buy a generic one and make it fit.
Gary

Re: Bigger fuel tank for a civic vx ?
 

I'm so confused. At last fill up when i was empty i only was able to put in 8.5 gals of gas in my 92 VX which would put it at 10gal with 1.5 gals still left in tank. Now i can get a range of 450m tops and have new O2 and my buddy has 92 VX and he gets 600m trips = 12gal tanks. Something doesn't add up here.
Is it possible that some 92 got 10 gal and some 12 gal as that link says 93 got 10 gal and 94 got 12 gal....wth is going on!

Re: Bigger fuel tank for a civic vx ?
 

I've put 12.84 gallons in my 11.9 gallon tank. I know there is extra space between the tank and the nozzle. If you check my gas log, you'll see I have routinely put very close to 12 gallons in my tank and over 11.9 gallons a couple of times. There's extra space that the specs aren't counting on these tanks.