stiffener cap question

The best way to setup a cap is don't install one. Do a search for caps in this forum, and read about all of the arguments... First and foremost, you need to put that money into a high output alternator. This is where the energy for a system compes from - not a cap...It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

caps are just for companies to make money off of people who dont know what they are doing

I agree. The only cap you need is on top of your head. I'm sure we'll get some negative feedback on this, like usual, but I've never seen a case where a cap helped any at all. '85 Toy

 I agree with the others, however by not knowing what the make model or anything else about your vehicle-sometimes you just have to make do - If you can not upgrade your alternator or use a dual battery isolator-DO NOT USE A CAP - tie in a BatCap 800.  It will eliminate many problems and certainly help those diodes in your alternator get through another winter.

I got much better bass after installing my cap.but I didn't buy some name I bought a cheap ass cap. I have found that after installing my cap I didn't get so many dips in my deep bass. Also I recomend a nice crossover every time from low end to comp systems they just make everything sound a lot crisper. Anyway I got my 1.5 farad cap for 43$ out the door and hooked it up to a voltage meeter, I got the same results from my "capp" brand cap as my buddys 169$ rockford cap. So buy a cheap one. The cap also allows me to use a much smaller amp by increasing the rms power since it holds a higher voltage constanly.Audiophile supreme