Anyone experience surging with the addition of an underdrive pulley on a car with a high wattage stereo system? Ive heard of things such as dimming lights happening with the underdrive pulley upgrade.

Thanks

 

Any high end system will cause draining. Using a capacitor along with a optima red or yelow top will help that problem nicely. Proper guage wiring is also critical. If you have any more question email me. I work at a car audio shop so i have more knowledge on demand if yo need more tech help.

 

I have a high end system:

Alpine CDA-7832
Alpine ERE-G180 EQ
Polk Audio DX 6.5 Components
Polk Audio EX 652a 6.5 coaxials
MTX 4180x (200w x 2) front components
MTX 2100x (80w x 2) rear speakers
Rockford 800a2 (800w x 1) subwoofers
(2) Kicker XPL 12s
Lightning Audio 1 Farad Capacitor
Lightning Audio Wiring

And as you can see Im already running a 1 Farad cap and most of my wiring is 2 gauge including the power from my battery and Ive also upgraded my battery ground to 2 gauge. Im just wondering the the addition of the Underdrive pulley will cause dimming due to the alternator pulley spinning less.

 

I would switch to 0 guage and add optima batteries to the list. Sure the pulley is slowing down the recharge, but you should be able to counter that.

 

How much more powerful than a Diehard Gold is a Optima red/yellow top battery? Also, you think moving up just a little bit in wire gauge will offset less draw from the alternator?

Just doesnt seem right to me.

 

I had a 2K Max auto with a full Eclipse A/V system with 2 JL amps and a Optima yellow top and no stiffening cap. No dimming or any problems with my UR pulley.

Dave

 

That sounds promising...maybe I should look into an Optima yellow. Do you know how many CCAs they put out?

 

I had unorthodox underive pulleys on my protege, 1farad cap and 700 watts RMS (not peak) and no problems

Everything functioned correctly..

ED

 

Same here. RF500a2(bridged 500x1) + RF400a4(50x4) + 1 farad cap + UDP = no problems so far.

 

When you test your ALT, do you put on all the electrical stuff PLUS blast your system?? Like, turn on your fogs, defogger, headlights. With all those running and your system blasting while your car i idling at below 1000 rpm. Now that's a test Of course, you probably don't do thid in real life, but when the car was stock it was able to handle it.

DW

 

Actually i tested my car on a load testor and got 62 amps from a 200,000 km alternator that was rated at 70 amps from factory fresh!!


Pretty good!!

ED

 

I'm concerned with the UDP as well. In my last car I put in a 210amp alternator and I needed to overdrive the alt's pulley in order for the alt to regulate full operating voltage at idle (14.4). I tested the alt with a clamp on ammeter that I picked up. I had it putting out 200amps AT IDLE and this was current leaving the alt and not the alt+batt output.
But now when adding the UR UDP, I plan to overdrive the alt pulley b/c I have a new 210amp alt for the max.

 

I dont see how an unorthodox racing pulley will affect you guys by that much...

It only underdrives accessories by like 10% i think it was,, but the belt size is only 1" smaller than original...

So don't worry most of the power gains is in the weight reduction of the pulley themself..

ED

 

UR underdrives 20%