:damnitcome on man!!:damnito save time and make for more complete answers please include details about truck model and year, approximate mileage, truck use, what you are trying do and what your goals are.i have a 86 freightliner. glovebox shows it has a 315 cummins in it. what is the difference in this engine and the 400. i have put a number 5 fuel button in it and it runs alot better. what else can i do to this engine to get decent power out of her?
Higher compression, slower cam, smaller injectors, slower timing, smaller gov spring, smaller damper, smaller clutch. Possibly shorter rocker arms (by CPL only)i want to know the difference in the 315 and the 400 Big Cam engines. i don't have the cpl. the year is a 86.