Underpowered RV

[rpaoness]

Borrowed my dad's RV (1992 Rockwood (Spartan Chassis) - 5.9BTA Cummins In-line 6, turbocharged). Seemed pretty doggy on the drive home, but I think weighs about 14,000 lbs and has 190 HP stock so I didn't really know what to expect since I'd never driven it before. I thought the turbo gauge was broken because I never saw it come up off of 0 psi (although this thing is so big, and such a large box with such a short wheelbase I was distracted by lots of other things on my first drive). I also had never had an EGT gauge, so seeing it roll up to 1100 deg or so on the worst hill on the way home didn't really seem that alarming. Got it home and started doing some basic maintenance, visual inspection, etc. I was surprised to find a ripped intercooler-intake pipe silicone boot/hose since I've never seen one break or age before. NAPA happened to stock the correct 3.5" diameter boot (was unfortunately $63, but I didn't want to drive around or wait for a cheaper one to be shipped). After installation during a test drive the boost gauge was suddenly active. Normal light throttle level ground cruising at about 60 mph is 8-10 psi, managed to get it up to 28 psi on the worst grades during my I-95 test. Night and day difference in how it drives.

[kevm14]

I have no idea how they managed to require 28 psi to make only 190 hp. I wonder what the exhaust manifold pressure is. That would be a fun experiment. I mean, I know it's at least 28 psi. Probably more like 35-42 psi.

What did the EGTs come down to?