cummin diy
 

are there any diy mods that i can do on my 2003 cummins?

You mean for increasing performance?

yes that is what he is meaning. He is wanting to do some stuff to it like i have been able to do with my 7.3

Can adjust the waste gate on the turbo, but I would get gauges first (if you don't already have them).

I do not beieve there is very much at all you can do with a third gen that doesnt involve cold hard ca$h.