My new engine is a little unusual to me.... it sounds great from inside the cab; sounds nice and healthy at idle with the amount of rattle I would expect; very smooth at all rpm above idle; idles perfect (to me) when cold.
However, if I step OUTSIDE the cab and the engine is warmed up, the idle seems a little rough with not as much rattle as I would expect. However, I'm wondering if it might be my old exhaust system (3.5" exhaust I pieced together years ago). If I pop the hood and stand next to the engine, I think it sounds great; but close the hood and listen to the exhaust, it just sounds... weird... to me anyway. That's why I was thinking maybe the engine timing could be advanced a bit....
Kinda hard to explain in words. But having driven 5.7L/6.2L/6.5L diesels for 27 years, I kinda expect them to sound a certain way. But this is my first 6.5L that I've completely rebuilt.
Come to think of it, the 6.2L I previously built sounded about the same after I rebuilt it. I always thought it had a weird idle when I was finished. Hmmmm.....
Casey
1995 K1500 Tahoe 2 door, 6.5LTD, 4L80E, NP241, 3.42's, 285/75R16 BFG K02's; 1997 506 block; Kennedy OPS harness, gauges, Quick Heat plugs, and TD-Max chip; Dtech FSD on FSD Cooler; vacuum pump deleted, HX35 turbo, Turbo Master, 3.5" Kennedy exhaust, F code intake; dual t/stats, HO water pump, Champion radiator; Racor fuel filter