Have any of you guys had problems with the alternator not holding up under load with 550-600whp and a lot of stereo stuff etc???

Maybe I just had a "bad" alternator...

Thanks.

 

Do they make one bigger for the VQ?

 

I've seen one other guy either on here or driver that had an upgraded alt. I don't remember how many amps it was, but he was selling it, USED, for about $700 IIRC. They are hella expensive to have made. A much cheaper route would be to custom fab a bracket for a GM alt.

As to your other question, I don't see how the amount of hp you're making would relate to your alternator running out of current capacity. Your alt doesn't care if your making 600 or 60 hp. As long as it's turning it's making power (albeit it will be happier at higher rpms).

What do you consider to be "a lot" of stereo stuff? How many watts continuous (not what your amps are rated, but how much do you think you're actually using)?

I have heard of our cars sputtering with an aftermarket stereo turned up a bit. It happened to me for about a week. Then I "debridged" my component set and I was able to turn the stereo up much higher before it sputtered. I then installed a grounding kit (custom made 10 wire ) about a week later and my car has not sputtered since. The gains on the amp have not been touched throughout the process, either.

 

Oh no, hp has nothing to do with it. It has to do with all of the stuff that requires additional eletro to make it all go at high whp and that including a highly stressful stereo system.

 

I should have read your post completely. So, you are telling me that your plugs would not get enough spark and would run rich and sputter when the stereo was turned up?

 

so you think the problem to this is your alternator? Didn't you unplugged the stereo to see if that fix the problem?

 

It could be that, but something was definetely being robbed of power. It could be the ECU, Ignition system, a sensor perhaps. All I know is that when I reduced the current draw and improved the grounding, the problem went away.

 

Basically, I pulled the plugs and they were black and two not firing. I replaced them and it ran fine. For awhile, until the new ones fouled as well. Of the three culprits for misfires (fuel, spark, compression) it was obvious that spark was the issue. It was thought to be coil packs, or crank angle sensor. However, upon replacing the plugs, it ran great. It has to be due to insufficient spark. Runs rich until it fouls the plugs and here we go again. I did disconnect the stereo and it simply just took longer for the plugs to go again. I am having the alt upgraded and replacing my bat. That's all I can think of. The system for engines is completely logical. This is all I can logically come up with at this time.

 

What are your major mods, just so I can see if your situation is relative.

 

I wonder how rich your tune is?

 

If your plugs are fouling that fast what is your a/f ratio?

 

12.96 to 13.56 at idle.

 

Remember, the stereo amps cut out when I get on it (WOT). So it's possible that the whole system is running low on juice and the more I stress the system, the worse it is.

 

What is your a/f under load?

 

Just put a Kinetix backup battery with an isolator switch and you shouldn't have power issues.

I would also put in an Optima Yellow Top for good measure.

 

Ya know, I really don't know. I will have to call the shop and have them pull up my chart. I'll let you know. Mark @ SGP Racing did the tune. I am sure it is good but I'll post it up for you anyway.

 

Got the Optima Yellow the other day. I could go the backup route but I really don't want to add anymore weight. Appreciate the post though.

 

why on earth is it so rich?

you should be in the mid 14's to high 14's at idle

 

you altenator effects your A/C and your stereo.. not your power output.. wonder if a beefy alternator can help your ac to be colder somehow.. AC in new cars still usues freon, right?

 

He says he doesn't want to lean it out until he can figure out why it fluctuates so much and why the stereo cuts out under load. Even that rich, it should not foul the plugs in 200 miles right?