My information is based on the work I did on my 87 300E, which has 4" MB quart coaxials in the dash and 2 8" JL Audio subs in a small sealed box in the trunk. Powered by a Soundstream REF644 (60W x 4, I think).

First, regardless of whether the speaker's width fits into the dash opening, its not a sealed enclosure. So you're not going to get much bass out of that spot anyway. My 4" coaxials fit pretty well, and I can see how 4.5" by somebody else would have fit too. But a bigger speaker probably would not have given more bass because there isn't a real enclosure Your best bet is to get a larger woofer in the door; if you have the 6" woofer side pocket (if your car is a later model), then MB quart has a three-way kit that will put a woofer there, with my coaxial for your mids/highs in the dash. If your car doesn't have this pocket, you can't simply add the newer pocket without doing some body work to the metal of the door. Sounds like the guy who added the 6" BA woofer to the door knows what he's talking about. Kick panel isn't an option because the emergency brake is there.

All bass comes from the trunk, which I didn't cut to make reselling the car easier. With 120W to each subwoofer(two 4 ohm woofers wired together with 2ohm stable amp)crossed over at 80hz, the bass gets through. It's not very linear, though; at lower volumes less bass gets through. At high volumes (and it get very loud) all the bass gets through.

My system sounds pretty good to me (Nakamichi MB-75 CD changer). let me know if you have any questions.

David
Dvogel@brainwavetoys.com