how big is your battery ? . . . original ?

 

with two w7's and just one 500 you've obviously got some serious current draw going on there, so that should get addressed first. are you sure the engine is actually surging or is it possible the bass is just moving the needle..?

 

Its a 750 CCA battery and it is not the original. Just replaced the original 2 months ago...

Yes, the needles do bounce around but, you can actually feel the truck surge when it hits those hard, low, beats...

I ordered a Rockford 2 farad capacitor last night. Should be here Wednesday, so we'll see if that helps.

 

how about your ground to the amp, and cables coming from the battery ?

bare metal? . . . for the ground? the better the wires and connection the less of a draw

 

More than likely the drop in voltage when the bass hit is causing some issues with the tune... Injector pulse width table comes to mind since it controls fueling and the table is axis on that table are Battery Voltage and intake manifold... Now it is not a tuning thing, but more of a side affect from your electrical system not being up to task for your stereo...

 

500 watts shouldn't be enough to cause that kind of a problem. I ran 1800 watts with stock alt and a redtop and I had dimming, but never surging. A capacitor really won't do a whole lot for your problem, other then cost money. Try doing the 'big 3' (google it) with 1/0 wire, and failing that get a HO alt of sorts.

 

I read something online that said you can run a wire from your alt. to your battery and ground, which is suppose to help with dimming lights... Anyone heard of this technique and could explain? It was in a forum and didnt go into real depth. Asked my installer buddy and he said he had never heard of it.

Buddy said the capacitor should help somewhat. Said the lights will still dim but not as bad.

If capacitor doesn't help the surging, I will be looking at a HO alt.

****Never mind...Just saw the "big 3" involves the wire from the alt to the battery and so forth...

Thanks everyone for your input!

 

Huge current draw = huge induced current needed in the alternator = lots of resistance on the serp system

Basically, your alternator gets very hard to turn when your bass hits and you are ideling and the engine near-stalls and the underspeed corrections kick in and rev the engine back up. Since the bass isnt constant it has to keep doing this over and over, otherwise it would only happen once.

Case in point, I had to put a 105a alt back on, and I can stall my truck if its idling just by turning my fans on high and my compressors on at the same time.

 

Thanks Atomic, makes a lot of sense now! Appreciate it!

 

JL's 500/1 with (2) 10w7 subs will definatly put a draw on the electrical system. JL's slash series amps have some *****. As far as the cap goes......I would have just installed a secondary battery. Maybe a little less expensive but your dimming/surging problems would be gone.