I have a older Cheyenne model ProChem portable. I bought it from my boss to start small and get bigger. Problem is he said the pump isn't going to last much longer. I started to use it and the pressure relief valve actually broke! So, since I'm changing out the pr valve anyway, and am going to have to buy a new pump, could I switch the pump for a 300-500 psi pump and get s larger psi pr valve? Will the older Cheyenne be able to handle it? And can I still use a 2 jet wand or will I have to upgrade to a 4 jet? Any help is appreciated