Low profile 8 subs?

Im looking for 8" subs that are really shallow, and can be set up in really small enclosures.

What is there out there.

I want to put them under my dash as an experiment.

JL audio has an 8" W0 ,W3v2 ,and W7. The W0's depth is 4.63" ,the W3v2's depth is 4.31" ,and the W7's depth is 6.83".

http://www.jlaudio.com/subwoofers/pdfs/6_8W0_MAN.pdf

http://www.jlaudio.com/subwoofers/pdfs/8W3v2_MAN.pdf

http://www.jlaudio.com/subwoofers/8W7.html

i did all my measureing, and it turns out i can only fit a 6" woofer.  I was looking at the MTX 6" thunder 6000.   I just need them to put out solid bass in the 70-200hz range.  I want to bring my bass soundstage forward more.

What else is there for 6" woofers that really slam.

"What else is there for 6" woofers that really slam."

That depends on what you mean by "really slam."  NO 6" woofer can move air like a larger one can, no matter what you do.  Anything smaller than 10" is probably out of the "slam" realm.  But if you want a good quality 6" woofer with great SQ that can, as you say, move your mid-bass soundstage forward, take a look at the excellent components from Scan Speak or Vifa.  If you can make it fit, the Scan Speak 18W/5535A is an excellent choice and can be installed free-air (no enclosure.)  Or if that is too big (it is a 6-3/4" driver) then there is a nice Vifa 5" that should work. model P13WH-10-04.  Another choice that I have had success with are the Focal poly-kevlar components.

Whell, im good for components, i have the alpine type-x 3 way's up front, and type-x 6.5" componets in the back doors, and in the very back i have 3 alpine r-12's with 3 mrd-m500's.

Problem is that my subs way over power my speakers, even tho i have the mrv-f540 running my mids and highs.  It makes it seem like i only have tweets up front and subs in the back.  I want to bring the sound stage forward when listening to low bass tracks, , , which is where the 6" sub will kick in.