can u make a box too big?

i am wanting to build a box for 2 type r 12 inch alpines, for my chevy HHR.

i plan on building a box that is 6.85 square feet.

also about 2-3 months from now i want to also add 2 of these subs to the box, so all 4 subs will share the same box...10" Clif Designs CD109W

1. is there really such thing as too big of a box?

2. what about having 4 subs in same box, is it big enough? would this just be a total **** up?

Either design your box for the two Alpines or get another two OF THE SAME sub and design it for 4.  I heartily recommend leaving the Cliff Designs subs out of the picture altogether.  Don't be a creative mix-and-matcher when it comes to subwoofers.

The type R wants a vented box, and typically a pretty large one, at that.  And yes, you can make a box too big just as much as you can make it too small.

I just wanted to clear up a couple things. 

#1:  Manufacturer specs for enclosures can be very helpful, but keep in mind that they are designed by the marketing department to produce a response to compliment their marketing goals.  This may result in a recommended small box with a peaky response just so they look like a small box woofer when they really aren't.  I recommend getting a good subwoofer modeling program so you can design it around your goals, not theirs.

#2:  When stuffing an enclosure, it is always best to put it out in the middle of the enclosure as much as possible.  Lining the walls is not nearly as efficient.  The purpose of the stuffing is to slow down the internal air speed.  The walls produce friction so the air speed is already reduced in that area. 

ok so i found each sub likes 1.7 feet, I can do that and just place wal inside the box for those subs and then be able to leave room later on to add 2 more type r's.

This is my idea, please comment on it. The box will be just a square

17 inches tall, 38 inches wide and, 24 inches length(front to back)

1 big 6.85 box, made from mdf 1"think wood. venting 2 type r's together on the top of the box, torwards the back of the box, then placing a wall width wise,  giving the subs 3.43 feet in area.

The later adding to subs in the front side of the box, Eehhhh???

It would look kool as heck, and i expect it to sound well,

Ok now here is the question where should i place the ports at, please help because i cant use those nifty programs to configure where they need to be placed and such.

I can do friggen wood work, but all that math( hwich i understand there is alot in audio) is all chineese to me.