FishOnOne wrote:
ShinerBock wrote:
Both engines can easily and reliably make well over factory power levels
I hear this statement from time to time but I have to ask why did Cummins change the internals to handle the 1,000 ft/lbs. I would have expected no internal changes if this were true.
What internals were changed? My Cuumins Quckserve shows the same internals. The main thing that changed was a CGI block to shave weight and a CP4 to increase fuel pressure to allow more power while meeting emissions. CGI blocked allows you to use less material due to it being a stronger material pound for pound so less can be used while having the same strength similar to how less "high strenght" material is being used in the frames.
The other reason for these changes may also be for future performance gains similar to how Cummins made to the 5.9L and 6.7L over the years by only changing engine tuning, fuel systems, heads, and turbo without changing any internals.
If it wasn't for these emissions requirements and future CAFE regulations coming to HD trucks that are bring mpg requirements to these truck classes. There are plenty of current 6.7L engines making well over 1,000 lb-ft with hundreds of thousands of miles on the clock.
