Originally Posted by CJGJR
I think the ISM was 11 liter and the new ISX is a 12.4 or something. Be nice to have the 14 liter 600HP in it, wouldn't it?
The old ISM, which I have, was 10.8 and maxed at 500 hp.
The Small version of the ISX was first 12.9. Then they re designed that engine and it was reintroduced as the ISX13. These were both 500 hp
The original and still big Cummins power plant is the ISX15. It's currently offered in motorhomes up to 650 hp.