box size

Hey guys, pretty new to subwoofers. I got a small subwoofer from a friend for cheap, jbl gt3-10 220rms. I was wondering if putting it in a bigger box would help reach lower frequencies, because my stock door speakers can reach about 50hz and the subs lowest is like 40hz but very quiet at that...

So I've had alot of help 2 to 3 people and all there information is great I just want to hear other people's advice that's all. So the box I need is 4 cubic feet net so there's a box that's 3.5 cubic feet net instead of 4 that would be a better fit in my car would that make a huge difference...

im looking to run 4 american bass vfl8d4's in a 1997 single cab chevrolet s10, but my one and only problem is i cant find any box size specs anywhere for these woofers... i would like to complete my transaction on ebay for all four, but, if all four arent going to fit in my truck why get four...