L5P exhaust upgrade what should be logged before changing anything?

Power/Fuel
1

I am planning some work on a Silverado 2500HD L5P and I want to establish a proper baseline before touching the exhaust side.The truck runs well but under a long pull I would like to know whether there is anything in the data that would tell me I actually have a restriction or airflow issue instead of just assuming a larger pipe will improve things.I am thinking of logging requested versus actual boost. MAF. MAP. EGT. Engine load. Fuel rail pressure and transmission temperature first.I have also been looking at an upgraded downpipe for L5P but I would rather have before-and-after data than judge it by sound or throttle feel.For those who tune diesels regularly what parameters would you record before an exhaust change?Would you also check for small boost and exhaust leaks first so the baseline is actually meaningful?

2

Welcome to the forum…

Sadly, their are only a hand full of hot rodders on this forum and most of those only deal with classic (gas) vehicles, and probably zero pro tuners on here, I have a tune on my Tacoma, but I just paid a tuner to do it, as I am sure any others that might run a tune have them installed… At most we have a couple, maybe a few, that would install their own tunes… Then you add in doing Diesel tunes and mods and you are probably just plain out of luck… lol

I would talk to your local diesel tuner and ask him/her what they think…
But your best bet for you to get the answers you are looking for would be to find a forum dedicated to your vehicle and performance…

Best of luck to ya…

3

Have you checked on forums dedicated to your rig?

4

My diesel never ran better after i took it to an actual diesel pro shop. They adjusted the injector pump timing slightly off from what the factory repair manual indicated. Even the olds diesel mechanic was unaware of the issue. So first i would discuss with the boys at an actual diesel shop. I remember we had an old guy on a farm that worked on heavy equipment. The dealers sent their problems to him. I remember him saying a diesel has to breath. Knew more than anyone.