Diesel truck tuning

I get how duration of injector pulse changes fuel injection and it's relation to timing and pressure but where do you start? What strategies do you guys use typically and without a dyno how do you know if you're going to far are there general rules for how far you can go with it?

Hi Tyler, you bring up some great questions and we're intending to provide detailed answers in our upcoming Practical Diesel Tuning course that is about to go into production. It's difficult to give a solid rule of thumb as every diesel engine is different and what is safe for a lightly loaded truck is not necessarily safe for that same truck towing a 5th wheel caravan for example. One of the keys is to monitor your exhaust gas temperature to make sure it's staying under control. A reasonable starting point would be to make a change to the delivered fuel mass of 10% and couple this with a similar sized increase in boost pressure. This will yield a noticeable gain in power without seeing the EGT sky rocket. It's also advisable to increase the fuel pressure to maintain a pulse width that's similar to stock. At some point you're not going to be able to do that and you may need to also advance the timing.

Alright thanks! That gives me a direction I'm working on a 2007 duramax and using efi live. So typically if you are looking to do some towing would you focus more on the fuel mass strategy and boost? I'll be installing a dsp5 switch because he's wanting to daily driver it with just a little extra and do some towing. He's going to be upgrading his exhaust and his intake but keeping his engine and injectors stock.