I installed a boost gauge awhile back on my 8.3 mechanical and I'm wondering how my boost number compares to others. I was thinking that you VMS guys will all have this info. I know B&C are getting up to 30. I am seeing a max of 25.5. Performance off the line and pulling hills is good. Just curious. Thanks.
jor
Sounds correct.
But, for specific information for your engine, call Cummins with your engine serial number.
The can tell you max boost for YOUR engine.
Cummins 800-286-6467
Do you have a pyrometer, as well, John? I sure miss those on this coach, tho I'm told, as long as the engine has not been 'hot rodded', there is no need. I sure liked them, though.
Here is a very long thread about turning up a mechanical Cummins 8.3, with some dyno numbers and boost numbers:
Brazel's Performance RV (BMC Service) - Wanderlodge Owners Group (https://www.wanderlodgeownersgroup.com/forums/showthread.php?t=5396)
(my previous coach)
Max boost will depend on altitude, temperature and whether the turbo has a waste gate or not.
Pyrometer is good as high density altitude, high temperature and especially mechanical engines can see high EGTs at lower RPM. One of the good reasons to keep revs up when climbing grades.
Pierce
99 ISC, I'll see 28.5 on the VMspec at 1750-2000 RPM on a hard pull.