Tyler254

Hi all, I recently completed installing a new sub/amp to my car and wanted to pass along my experience. I spent a lot of time online looking for info from others who did it but didn't find much.

I first explored the possibility of just replacing the stock 8" sub in the rear deck. After calling around to a few places I was told pretty much the same thing, that it wouldn't make much of a difference. I had planned on doing it myself and didn't want to undertake the risk of removal and replacement, especially considering the extra steps (soundproofing, spacers, etc) others had mentioned.

After hearing a demo in-store, I opted to purchase the Rockford Fosgate P300-10 which is a 10" enclosed sub with 300 watt amp on board. It was fairly inexpensive and less to worry about than a separate speaker/amp situation. The P300 also comes in a single 12" with the same amp. I chose the 10" to save a little space and a little money. I found this model online in the $200-$270 range and they wanted to sell it in one local shop for over $300. I got mine on Amazon for $162.00 and free Prime shipping!


Installation:
NOTE: I did not install a line converter from factory sub. I chatted with someone online from RF who said I could simply cut one half of the supplied RCA to hi-range plug and wire the original sub wires right to it. I did this and it works fine. No signal loss.

I also did NOT install a remote wire. This amp comes with "auto sensing" feature which will turn itself on when receiving a signal from the speaker wires. I've seen some videos with other people installing this amp as well as a remote. Not needed, save yourself time. If you really want to, you can.

As others mentioned, there's almost no way to get through the firewall without drilling. Mine is a lease so I didn't want to. I struggled for several hours trying (and finally succeeding) to get the power wire (8 gauge) through the small hole for the hood release cable. My hand would not come anywhere close to fitting right next to the hole--too many other cables and wires I couldn't move. I first tried to move the existing rubber grommet to the side and squeeze the power wire past. That didn't work. I was able to just pull it out and keep it on the hood release cable but free up the space in the hole. This way I can return the grommet into position if needed. It took a lot of trial and error to get the power cable through the hole. I used a long screwdriver with the cable taped a few inches down to push it through. I could then remove the tape and push it through a bit further by hand. This puts the cable between the fender and the engine compartment. I used my wife, a bent clothes hanger and a pair of large grill tongs to retrieve it from the fender well and pull it through with one person pushing from the inside and the other pulling with the tongs. To do this, you obviously have to remove the plastic piece inside the engine compartment which covers the fender well. Four cheap plastic clips hold it in. I broke 2 1/2 of them. To get them out without breaking, gently slip a flathead under the top part and then pull the bottom part out. The cable is easily run from this point to the battery. I zip tied it in two spots to another covered cable in the engine compartment. The in-line fuse is just kind of wedged in there for now. Not sure if I'll leave it that way.



Below is a close up of the firewall hole you have to find and then figure out. You'll see it on the left side, with the clear power cable coming out. Note the factory grommet slightly behind the hole, still on the hood release cable. I'm not sure if I really need to add anything to hold it in place. I'm sure it won't move on its own.









Installed in trunk. There's still a bit of space behind the sub. I didn't get it far back enough when using the supplied Velcro to secure it. I grounded the amp on a bolt which becomes visible when putting the back seats down and removing the trunk carpet. There are two bolts you can use--I chose the one that goes directly into the vehicle body.





Here you can see the amp inputs on the side of the box. The amp features a quick release bracket which is good if you ever want to remove it but keep the wiring in place. I used standard butt connectors for the audio wires from the original sub. The factory sub has RED and YELLOW wires. They're both copper and apparently aren't pos/neg (as was explained to me) so it doesn't matter how you wire them into the supplied plug. If you use a line out converter and the supplied RCA cables (which you don't need to do) then the way you wire them is important.




So far, so good. This thing sounds great and is what this factory stereo has been missing for too long. I've got the gain set about halfway with the bass boost at zero. Audio setting has the sub at halfway. This thing hits pretty heavy and has a LOT more to give if needed.

01LSi

Do you have a pic of the grounding point you used? Is it the one next to the rear seat bolt? Someone mentioned a grounding point on the rear side seat bolster but I didn't see that.