Alternator charging 17v ???

So as you can see my alternator is charging 17v. Ive recently extended the alternator cables in order to hide them and make my engine bay look neat.I dont know if its my fault and ive done something wrong ( i did double and triple check my wiring and its all fine) Could it be the batterys fault? my battery is really old and tired now.

I'll try to see what sort of voltage i get when i use all the electrics in the car and see if the voltage drops. Any other ideas why its doing that?

That does sound quite excessive typical reading from an alternater 13v -14.5 v ... where are you taking the reading from ???

straight from the battery terminals

regulator could be toast

Had you tested it before doing the wiring? Or just after?

Sounds like regulator, alternators make more than 14v but the regulator controls it so it doesn't not over charge the battery.

And the regulator is built in to the alternator.
It used to be possible to buy the regulators and swap it out in the alternator, but I don't know if it can be done on these ones.
Swap the alternator while you've got the aircon off..
http://www.howacarworks.com/electrical-systems/fitting-a-new-voltage-regulator

yes as above will be the voltage regulator blown
don't run the car with those volts going through it or it will fry your battery if it hasn't already done so

Could it be because of a shitty connection somewhere on the ground or signal going to the alternator? I've done some work on the wiring so maybe its my fault ;/

Would any sr20 alternator fit my pulsar? there was a primera gt on my local scrap yard that ive spotted couple of days ago so i might rip the alternator out from it