Will my car just die if I have underdrive pulleys with the A/C, Headlights and a 400 watt stereo on? I'm thinking about the JET Pulleys.

 

The engine won't die, but the alternator will have trouble putting out enough amperage to run the car and keep the battery from discharging at low engine rpm. As you drive though, it should be fine. But when stopped, with the radio, ac, lights, wipers, rear window defogger, etc. on, you will notice a definite power problem.

 

Pulleys and a high watt stereo, The only answer is NO, its like oil & water they don't mix. So called performance pulleys are good only if race a lot and do not care about your charging system as a daily driver.

 

I put them on my car and my alternator went bad 2 days later, I think it was on the verge of dying anyway and the pulleys just killed it. So i went out and bought a 110 amp alternator, and i havent had a problem since. You just cant blast your stereo if your waiting at a light, no big deal.

 

....oh and by the way, if anything happens your subs will probably cut out until your alt. starts charging again, ive heard of that happening before. On a car with stock pulleys the alt. probably wont be putting out any useful voltage until about 1500 rpm, after the pulley install you will probably have to bring it up to 2000-2500 for any useful output.

 

Look elsewere if you want more power. People have problems without stereos. Running them with is proboly asking for trouble. I got a 150 watt punch amp hooked up to 2 6x9 without problems. It really depends what u have that 400 watt amp hooked up too and if your going to play it full blast all the time.

 

Life is full of compromises..I'll stick with my Kicker Comp VR's..much more worth it than the 17 RWHP..

 

I doubt you will even get that much.

 

For 17 RWHP those pulleys must be the size of DIMES.
He better keep his kicker comp vr & etc, because he knows nothing about RWHP.