is there any way of finding good ground points in your car without actually hooking up the amp? i don't want to keep drilling holes in various places to hook up the amp and testing it with the dmm. if there is a way i can use something like a dmm or some other equipment to test it let me know please.
cant you connect the red on the dmm to the battery and then jus put the neg on whea youd lik to know if its a good ground???idk tho, or maybe put it ohms and connect one to battery and the other to the spot to see if it goes from teh battery to teh ground???
You'll need a DMM and a long wire. Put your DMM on ohms (lowest range if not auto ranging). Touch the probes to the ends of the wire, and record the reading.
Then connect one end of the wire to battery - Touch one probe to the other end of the wire, and the other probe to the spot you want to test. Record that reading, and subtract the reading you got from the wire.
If you get almost 0, you've got a good ground.
Note that this only applies to unibody vehicles, which Chad's is. With a full frame vehicle you would need to ground to the frame. Reason is the body sits on rubber mounts and is grounded to the frame with ground straps (often not big enough to handle large amplifiers). If you did this test on a full frame vehicle you would appear to get a good ground, but under load the ground straps would not likely carry enough current for a large (say 4kw) amplifier.