CM 870 looking for more power

[Rawze]

First of all, putting in the spring loaded gears is simply a waste of moneys and frankly, bad choice vs the straight gears. They have absolutely no advantage whatsoever, are more problematic over time, and can cause catastrophic gear train damage if not installed exactly right. It will also NOT change anything power-related whatsoever.
Here is one example of this .. about half way down the post...
ref: http://rawze.com/forums/showthread.php?t...2#pid25522

The actual tier2 (mid-tier) to tier1(high power tier) hardware changes are bigger injectors, different injector and valve cams to go with those injectors, different pistons, and sometimes a different head with the bigger exhaust valve openings too.

Also, with a heavy haul operation and higher average HP loads, you need the larger 500-series model VG turbo to go with that too. The turbo with the titanium (high heat) exhaust turbine is required for heavy-haul.. and not the one that is made for more fuel efficiency.

3.90's aren't terrible, but they are in the upper end vs what you are pulling. Some 4.33's or better yet .. some 4.86's would be my choice.

Also, the 0.013" liner height is a bit low. Should have been 0.015" - 0.016" + re-torque head after letting it sit over night, + al the other things to do to make a million mile+ engine etc.
ref: http://rawze.com/forums/showthread.php?t...6#pid70606


lastly.. it is the high torque + driving it below 1500 in a hard pull that wears out these engines. 600 HP is fine .. but 1850trq is as high as someone should go.. plus learning to keep it above 1500 when pulling hard, backing off of it and using lower gear ranges so that your foot is not all the way in the floor all the time + to get the rpm up where it should be (1500 - 1900 range when pulling).