Can't win

[Rawze]

my cm871 bounces around in the 11 - 14 mg/stroke range all day when idling at 800 rpm. always has.

I have seen some guys be as low as 10 or so, and some up in the 18-24~ish... those are all normal in a de-mandated engine, or engine that is fully warmed up and is not trying to warm up the exhaust.

On a stock engine,.. its in the 28+ range after warmup and as much as 40+ at times when its keeping the exhaust cans warm (thermal management modes), but sometimes will drop for a while, then back up again when its fully warm in a long idle state.

One of the biggest factors is how tight the rings are in the engine. I can tell by hand if an engine is going to be a fuel pig at idle, or will be kind to its owner. -- How much carbon packing and buildup in the rings is the #1 differences. - its not really the actuators, or other things unless something is notably wrong with one... Engine does not even have to run real smooth, as long as it is not stumbling, etc.

One guy can have a really easy enigne to turn by hand (like mine, everyhting clean as a whistle well cared for, and well lubricated with gear lube), and the next, its 2x harder for it to be turned over, rings are tight, sharp on their edges, carbon packing, etc.... that or they have after-market piston/liner kit, or non-oem rod/main bearings, etc. and it has more friction.

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The common rail engines are NOT more fuel efficient than the CM871, -- not all at all, not one damn bit. - i have seen a few get really close with a lot of tweaking,.. but as a general rule,.. they are .1 - .3 mpg less fuel efficient even with all mods done..

I have only seen a few guys get their 2250's or 2350's up in the low-to-mid 9's consistently and those were guys running so light, that my prostar would be breaking 10's on the same loads.