Curious questions

[rraccerr]

(02-28-2019 )Rawze Wrote:  

(02-28-2019 )rraccerr Wrote:  2014 t680 with a ISX 15 400 Cummins. Two questions i would need help with.

1. My sweet spot on my rpm meter is at 1300 rpm. That’s where I keep my engine running over the road. But I read that an ISX should be kept at 1650-1800 to get best performance, is this true? And if so, should I forget about that sweet spot indicator?

...

there is no "sweet spot". 1300 is too low rpm for pulling power (when you need a lot of boost). it is better to have it in higher rpm range - 1660 or so when pulling hard. - When not pulling hard, it is better to use the lower rpm.. it changes with loads and terrain and requirements.

http://rawze.com/forums/showthread.php?t...8#pid24378

My rpm gauge has two green bars and the middle of those bars is at 13 rpm and my trip summary shows it is a sweet spot. I have a 400 ISX 15 and it’s been bumped to 485 so my bars been adjusted to those rpm levels. But I’m grateful for your response to my question and will look forward to applying this and let you know how it went. Thanks