Mounting Polk Sr 6500's

[Stewart8989]

I've got an 05 mustang in which the door panels have 8 inch subs in them already. What I have done is make an MDF circle that will fill the gap between the 6.5 inch woofers so that I can mount them to where the subs used to be. When I say sub they are very shallow and the enclosure that Ford designed for them is a little less than a 1 cubic foot. My question is should I use the existing enclosure or should I just cut out the back. I assume these are supposed to be mounted in an open air environment, so would putting these in that enclosure without cutting something out make them sound worse? My only concern is that they are not mounted to any metal on the actually body panel but rather the plastic inner body panel of the door. As a result it isn't the stiffest mounting surface and at louder levels I can imagine some serious vibration is possible. At the moment I have them in there as is, without cutting any of enclosure with some dynamat inside the enclosure and on the outside (side facing the inside of the door) of the plastic door panel.
If anyone has a ny suggestions they would be appreciated. Thanks.

 

[Bbisig]

If the enclousures are sealed you might have a problem over extending the speaker if its ported I would see how it sounds first then modify the enclouser if it sounds bad.

 

[dodgerblue]

ive seen somewhere that the mustang door enclosures measure about .4 cu ft , no worries about OVER EXTENDING your polk mids as its much more likely in ib-ported fasion and is a non issue , listen in the enclosure and go from there - a decent size opening on the enclosure may help a bit in the m-r mid bass response though .

 

[Stewart8989]

You're right I checked they're .4. I have yet to get my whole system tuned but at the moment I think they sound pretty good. I have no reference point as to what they would sound like in another mounting set-up but I just want to make sure I'm not muffling them in any way. The only other advantage I could think of is that if it wasn't so sealed it might cut down on the vibration in the panel since it is only plastic.