Here is a setup I might use....when I buy an H1 hummer maybe...I don't think it will fit in the cobra.
From MTX's web site:
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Have you ever noticed that the people who go to the extreme of customizing their $100,000 cars with the biggest and most blinged out wheels, custom alligator skin interiors, and even steering wheels encrusted with diamonds always seem to have the same 12” woofers as the 16 year-old kid down the street? For these people, the word “excess” doesn't cross their minds when it comes to customizing their car. So, MTX has crafted an all new, 22" SuperWoofer for anyone who's got what it takes to go to the extreme—the MTX Audio JackHammer T9922.
JackHammer is the most enormous, mind-blowing subwoofer ever created. You will literally not believe it until you see it. Standing in at 23” tall, 320 pounds, and with 10,000 watt peak music power handling, you will be hard-pressed to find something that will get in the ring with this heavyweight.
Carbon fiber and glass fiber dust cap with aluminum honeycomb center
Expanded polypropylene cone with mica filler for reduced mass and increased stiffness
FEA designed progressive roll spider with 10 AWG integrated tinsel leads woven in to allow for 2.5” of linear cone movement one way
900 ounce strontium ferrite magnet with extended magnetic field gap technology and aluminum shorting ring
6.5” voice coil with a flat wound, long-excursion design incorporating 2.5” of x-max and 17 AWG high temperature aluminum wire
Aluminum heatsink to maintain the optimum voice-coil temperature
5,000 RMS, 10,000 peak music power
94dB sensitivity @ 2.83 volts
The JackHammer SuperWoofer represents excess in every way and this enormous subwoofer lives for high SPL and window shattering bass. But, the T9922 is designed for sonic quality, and high SPL, what we call SQL. JackHammers are shipped in either the SPL mode, with dual 2Ω voice coils, or as the SQL model with dual 4Ω voice coils. A replaceable cone assembly is also available, for switching between "every day" listening (SQL), and competition (SPL). Unlike traditional replacement assemblies, the MTX Audio Thunder9922 replacement assembly can be accomplished without removing the speaker from the enclosure. Fast, quick, and easy.
T9922-44 22” JackHammer SQL SuperWoofer,
Dual 4Ω (5000 W RMS)
T9922-22 22" JackHammer SPL SuperWoofer,
Dual 2Ω (5000 W RMS)
1989 5.0 - Mustang Brandy the NOW It can Barely Idle B**ch 
