I'm just wondering what engine RPMs people have hit by accident or routinely do (over redline) with their diesels. I got stuck in some soft mud today while four wheeling and as I was trying to get out I hit 3500-3600 RPM.

 

i hit 4000 once in my 04.5, while playing in a field. i don't think you need to worry if you don't run 3500 rpm for a sustained time

 

Good to know, I revved to 3500 RPM twice while stuck for an hour, and it idled in between each try.

 

Ive tached to 3500 right as I dumped the clutch in 3rd[sm=gears.gif]

the CP3 I believe can fuel unloaded to 35-3600 rpm and while 4k can be hit, without any damage. however, sustained fueling at that level is a bit hard unless you have a good lift pump or aftermarket pusher with a fueling box.

at 4800 or so RPM a harmonic develops and the crank is literaly puked out of the oil pan.

many guys that use these trucks for tractor pulls have the engine built to fuel to 4500 RPM and sustain that engine speed for the pull.

 

So if I upgrade the fuel delivery system, the engine is rugged enough to withstand trips into redline? Thanks for all the info, I'm new to diesels and there are quite a few differences compared to gas engines.

 

the computer will de-fuel the engine to prevent from destroying itself. Most of the guys that are running these insane RPM's are 'P' pumped (P7100) and these pumps can push WAY more fuel than the CP3 can. the main purpose for all those revs is just to be able to turn the wheels faster for any given gear.

The engine itself in stock form will live all day, night, and into the next week at 2500-2900 RPM. when you push into the 3k range things get a bit dicy since the engine is starting to run out of it's power band.

when it comes to diesels, HP doesnt mean everything. Torque is the issue. I have witnessed a 900hp(#2 only) diesel dragster twist the drive shaft and bust the yolk that a 1500hp pro mod running all the drugs couldnt. if you look at the power curves between diesel and gas you will notice the HP curve acts the same with both, however the torque curve can increase by as much as 400ft-lb in less than a 100rpm span.

if you are looking at turning high RPM numbers then you better break the trusty checkbook out and better hope the well runs deep.

me, I'm looking at inexpensive ways to increase power not by turning more RPM's but by increaseing the timeing, duration, and fueling my injectors do between 1500 and 2500rpm. However, the occasional venture over 2500 is fun and is needed to put the ricers in their place

 

I thought the factory governor setting on these trucks were 2900 rpm's?

at leaste that is what i was told for my 05 2500 quad.

when i drive on the highway sometimes 75mph+ with the 4.10's in the rear it is taching at around 2500rpm's, and honestly i didn't even give is a second thought. Am i to believe that i shouldn't be taching over 2500 for too long?

remember "DON'T SPEED"

 

the engine speed govenor hits at 35-3600. at 2900rpm the engine is making max HP.

the cummins engine will live just fine at 2500rpm. granted I keep mine around 2300 in 6th(70mph) due to fuel mileage, but I'm not afraid to put my foot into it and run it up to 3k for a little bit

 

Oh... I was under the impression that there was a rev limiter that would only allow the the engine or rpm max out at 2900.