So, currently I got my MB Quarts installed in the front doors and I am powering them off a PPI 4800(important later), I was also able to get an audiocontrol 4xs of ebay.($80 money well spent). Either way, Now I am starting to think about how to layout the trunk, and honestly I would like to keep as much space as possible. I am thinking about 2 10" subs and of course the 4800 and the audiocontrol. I am thinking I want to mount the subs to a board and then the board to the rear deck. Since I can remove the rear deck, I could measure the wood perfectly and then using the numerous holes, mount the board to it. Then put it back into the car and mount the amps. As for the subs, I am think about something backing up to the seats and facing the trunk lid. I am quite curious about everyones views are about mounting the amp upside down. Many have said heat is an issue, but honestly I am not even touching what the amp is capable of. Also this is in an S4.

was that it started to clip and sometimes shut down after long periods of time ( usually waiting in LA trafic :P ) - the amp got extremeley hot !!and i was running a 4ohm load to 2 8' subs. The amp is/was a sony mobile es 50 X2 chanel amp. It a fairly good amp.
Does the ppi amp have built in fans? if so then i think it will be OK for a while, but i suggest that you think about mountng it else where if possible, for instance you can mount it on your box and make a very nice subbox/ amp rack combo that looks clean or mount it on the rear seatback. there are lots of ways-

And its not like the ppi amps are ugly - they are very nice looking and especially since you have a silver car (BTW silver is faster :) ) you should show off the amp some. IMO

peace

dissipate heat off the top of the amp. by mounting it to the bottom of the rear deck upside down, the heat dissipates down, then rises right back up onto the amp. this causes the amp to get extremely hot and will cause it to clip

most amp designs have the heat sink on top and are meant to be mounted right side up. If you mount it upside down, heat rises, thus you are basically drawing all that heat right back through the main circuit board... that's why it went thermal on you.

I still have decent trunk space but the amp has better cooling since the heatsinks are allowed to do their job. The shelf is nice as well, pulls out to gain access and is held by set screws so that the amp doesn't become a battering ram.

My amp, an esoteric 6 channel states in the manual that it can be mounted in any position as long as it has 2" of airspace around it. It has a small fan inside of it that draws cool air across the circuit board and through the heatsink.

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