I have went through about 7 altanators in the last 5 months. Basically when I run at the track or flog it,it burns the alts up.I can drive it normal and does great but if I punch it the brake booster code and alt not charging code flashes and there goes the alt.Is it possible for this to be a tuning issue because the truck has not done this untill I had it re-tuned. I have check and made sure that I have no bad grounds or any wires crossed. What do ya'll guys think?

 

That doesnt sound right at all! but guess when making hard passes and driving it hard that puts strain on them.
free bump!

 

What kind of RPMs do you turn when flogging it?

 

I'd guess your spinning it too fast but some guys on here are shifting at 6900rpm so I dunno.
The only time i've gotten the brake booster code is when It Idles way down and doesn't have enough vacuum. Stupid question but is it spinning backwards?

 

I am spinning it to 7000 rpm. Is it possible to spin them to fast? No it is not spinning backwards.After I burnt the acdelco alt up I went to autozone and bought one of those lifetime warranty alt.My tuner guy says it is the cheap alt they are using aftermarket regulators on them when they rebuild them. I thought it may be a tune thing after the 7 one.Of he is not going to say it is that is why I asked ya'll.

 

I can't see a tune having anything to do with an alternator. I only asked about spinning backwards incase they could have given you the wrong alternator.
What does your Voltage look like normally? does it move any when you idle cruise and hit upper rpm's?

Just trying to get some Idea's here.

 

Might try putting a little larger pulley on the alt and see if that changes anything.

 

or an underdrive pulley if you don't already have one.

 

I have got stock pulleys.Well I have notice back when it was really hot out side It would move a little when I would run my ac, other than that I never notice anything out of the ordanary. I took the the one I burnt up friday back to autozone satday when I got back I put the new one on it with an extra external ground wire and then took it out and as soon as I matted it the voltage gauge looked like my tach.I took it off and took it back the zone the testedi it and it had burnt the regulator up.

 

It will produce less amperage when not racing, but will cure the problem nonetheless. Perhaps have a high output alternator made that will put out 250+ amps, but saddle it with a larger than stock pulley so it doesn't spin as fast. You might actually see this one outlast a stock alternator that never sees race time in it's life. In theory, it will produce stock amperage, yet never spin faster than a stock alternator even at 7000 rpm's, therefore it will hardly be working as a DD.

I know this works to some degree because I had a 280-300amp alternator made for my trail rig. When rock climbing, engine rpm's are rarely above 1000 yet I use a winch on occasion to get me through tough terrain. I had the shop put a smaller pulley on my alternator to spin even faster at low rpm, fully knowing my truck's red line is 6000 and will hardly see above 3000 as a DD. You will be going the opposite route as I did, so I don't see this being a problem with a higher output alternator peg-legged with a large pulley.

Edit: Don't forget to replace the alternator cable that goes to the battery + with a thick cable. Preferably 2 gauge or bigger. I bet a big portion of burning the alternators out is spinning the amperage up so high without it having anywhere to go through those thin stock wires, and perhaps a battery that cannot keep up as well.