How many people have hit 4000 rpm's, and how many times.

Mountainman · **Posted:** Tue May 17, 2016 11:51 pm

Since I accidentally hit 4000 today, when I intend to never exceed 3000, I was wondering how many people bring their engine to redline, and if many times, or once etc. I got a little over zealous when someone tried to give me the squeeze with my lane ending... This engine definitely spins up faster with an almost new top end vs old rockers and cams. I need to be more careful I guess :banghead:

Maybe the tach can overshoot a bit, and I didn't actually hit 4k?

undrgnd · **Joined:** Sat Mar 26, 2016 4:47 am **Posts:** 194

Lol I do it all the time

are you not suppose to? I overtake people all the time as I live in a very open place that we only have single lanes.

flash7210 · **Posted:** Wed May 18, 2016 8:40 am

I've never experienced the need to rev my engine above 3000. Not even in an emergency situation. A few times I have accidentally bumped the OD-off button and that sent the rpm up to 3500 but I quickly got off the throttle when that happened.

I can see how, if you are between 34 and 50 mph (4th gear, TC unlocked), punching the throttle can force a downshift into 2' and send rpms way high. But most of the time, at speeds where the TC is locked, the engine still has plenty of power to speed ahead without forcing a downshift. Although this can induce shudder if you have a weak TC clutch.

A lot of times when I'm driving at speeds below 50mph I'll have OD-off. This will allow the TC to lock at 37mph in 3rd gear. This allows for plenty of acceleration without the need to downshift and when I am comfortably above 50 I will turn OD-on.

I really wish this transmission had the "auto-stick" feature that many other chrysler vehicles have. This would provide a better means of manually down shifting when needed.

thermorex · **Posted:** Wed May 18, 2016 9:22 am

I mistakenly hit the Overdrive switch on the stick, and it jumped on 4000+, right away I pushed it in neutral and realized what I've done. Knock on wood, all good so far. Usually I go up 2500 rpm, once in a blue moon I go over.

mass-hole · **Posted:** Thu May 19, 2016 9:37 pm

4000 rpm? Please. I've hit 5000 a few times when I had the ram TCM and it kicked down too many gears.

I don't hit 4000 often but probably a few times a month. I don't think there is any reason the engine cannot spin this fast, I think its mostly because of the diesel burn rate and the turbos lack of flow to keep forcing enough air into the engine.

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Mountainman · **Posted:** Thu May 19, 2016 11:37 pm

mass-hole wrote:

4000 rpm? Please. I've hit 5000 a few times when I had the ram TCM and it kicked down too many gears.

I don't hit 4000 often but probably a few times a month. I don't think there is any reason the engine cannot spin this fast, I think its mostly because of the diesel burn rate and the turbos lack of flow to keep forcing enough air into the engine.

Sent from my Nexus 6 using Tapatalk

Thankyou! That's the post I needed to help me worry less about the new pst, pst, pst, pst sound I have that is coming from the bottom end or the transmission (or at least that's what a quick listen made me think). Maybe it has to do with the fact that I still have shudder with a new hemi TC and an updated pump.
I'm still sticking with the 3k max though. I want to see if the bottom end will last until 500k. I'm afraid the wiring is going to wear out and drive me nuts in another 10 years though, long before the bearings and rings...

mass-hole · **Posted:** Fri May 20, 2016 9:14 pm

Mountainman wrote:

mass-hole wrote:

4000 rpm? Please. I've hit 5000 a few times when I had the ram TCM and it kicked down too many gears.

I don't hit 4000 often but probably a few times a month. I don't think there is any reason the engine cannot spin this fast, I think its mostly because of the diesel burn rate and the turbos lack of flow to keep forcing enough air into the engine.

Sent from my Nexus 6 using Tapatalk

Thankyou! That's the post I needed to help me worry less about the new pst, pst, pst, pst sound I have that is coming from the bottom end or the transmission (or at least that's what a quick listen made me think). Maybe it has to do with the fact that I still have shudder with a new hemi TC and an updated pump.
I'm still sticking with the 3k max though. I want to see if the bottom end will last until 500k. I'm afraid the wiring is going to wear out and drive me nuts in another 10 years though, long before the bearings and rings...

I mean this engine doesnt make much more power beyond 2800 rpm anyways. Unless you need every last drop of power you shouldnt have to go beyond 3000 rpm.

GDE's eco and hot tunes only makes another 12 hp after 3000 rpm. The stock tune only makes another 7!

apardo001 · **Posted:** Sat May 21, 2016 12:44 pm

You're right, the engine will not produce much power above certain point, but going above 3000 rpms for 5-10 seconds is not a big deal for engine durability, different words if you're offroading/towing and keep it above 3000 for longer periods of time.

Durability, among other things, comes from diesel engines running low rpms (high torque) during long trips vs gasoline engines having to stay on higher rpm ranges (high HP) to keep up.

In my case, when passing trucks on mountain roads I don't worry that much about RPMs, prefer to get by faster rather than staying on the opposite lane.

65Corvair · **Posted:** Sun May 22, 2016 12:48 pm

I probably go over 3500 once or twice a week, if I am in the mood for some "spirited" driving. Once all warmed up of coarse.

camo · **Posted:** Sun May 22, 2016 9:27 pm

I do OD off highway driving once or twice a month going to work and it runs like at 3200 rpm (LOVE IT) and I have been doing it for the last couple of years with no issues (knock on wood), so I don't see why would a little of 4000 rpm driving would hurt. :JEEPIN:

Mountainman · **Posted:** Sun May 22, 2016 10:18 pm

Thanks for all of the responses, now you all have me wondering how many people hit 4500 and 5000 :jester:

lacabrera · **Posted:** Mon May 23, 2016 3:06 pm

I seem to remember there is a 4000rpm rev limiter programmed in the ECU. Maybe its on the manual trans only? its way to easy to red line it in 1st and 2nd when you push it.

Mountainman · **Posted:** Mon May 23, 2016 6:07 pm

I don't know about any limiter, but I wish mine had one at 3000. I'm going to ask Keith about one, because I can't seem to keep it as low as I want these days.

psCRD · **Posted:** Tue May 24, 2016 9:17 am

Mountainman wrote:

I don't know about any limiter, but I wish mine had one at 3000. I'm going to ask Keith about one, because I can't seem to keep it as low as I want these days.

Isn't that what Limp-mode does?

Mountainman · **Posted:** Tue May 24, 2016 11:14 am

I believe that limp mode sets the injection at a certain point, and quantity (low) and thereby limits power. It's got to be injecting fuel at a non-optimal point since they smoke so bad in limp mode, right?

flash7210 · **Posted:** Tue May 24, 2016 11:24 am

When I was having fuel system problems there was never any smoke. Just low power.

Now, if it were limp mode caused by a turbo/boost problem, then I'd imagine there would be lots of smoke.

lacabrera · **Posted:** Tue May 24, 2016 12:54 pm

flash7210 wrote:

When I was having fuel system problems there was never any smoke. Just low power.

Now, if it were limp mode caused by a turbo/boost problem, then I'd imagine there would be lots of smoke.

x2 no smoke just low BHP. 3000 RPM limiter that can be switched off occasionally would be useful. Only problem I find with this diesel is its very narrow power band compared to more flexible modern diesels? not much torque below 2000 RPM and than fades out at not much more than 3500 RPM.
Just took a test drive in a 2.3d 1 series BMW with a twin turbo. words can not describe it.

wilco549 · **Posted:** Wed May 25, 2016 11:04 am

How can you drive one and keep it below 2500? or even 3000? I regularly spin up to 3k during acceleration and have pushed 4k a few times when feeling my oats. One time the accelerator jammed on a floor mat while passing another car. I don't remember looking at the tach but it was floored and the engine was wound up tight for 15-20 sec...i was too busy trying to un-jam the pedal. :ROTFL:

admittedly I do drive aggressively. I take off like I'm in a drag race leaving the car behind me in a cloud of soot. :pepper:

Mountainman · **Posted:** Wed May 25, 2016 12:12 pm

wilco549 wrote:

How can you drive one and keep it below 2500? or even 3000? I regularly spin up to 3k during acceleration and have pushed 4k a few times when feeling my oats. One time the accelerator jammed on a floor mat while passing another car. I don't remember looking at the tach but it was floored and the engine was wound up tight for 15-20 sec...i was too busy trying to un-jam the pedal. :ROTFL:

admittedly I do drive aggressively. I take off like I'm in a drag race leaving the car behind me in a cloud of soot. :pepper:

Definitely tempting with these engines. I just figure I'm not really getting hardly any more power, and maybe keeping it low rpm's will keep it on the road longer. I want to see if the bottom end can make 500k. I've already replaced almost everything else, but the top end was cheap enough with slightly used parts. More importantly, I pack-in where the trailhead is 80+ miles from the nearest tiny town (which has limited services), so I don't want to spend a week walking out at the end of a back-country trip where I've already eaten most of my food :ALONE:

I do keep extra chow in the jeep, but still

flash7210 · **Posted:** Wed May 25, 2016 12:12 pm

wilco549 wrote:

How can you drive one and keep it below 2500? or even 3000? I regularly spin up to 3k during acceleration...

How well does your CRD accelerate/hook-up with the new Hemi TC?
Does it feel tighter than the stock one?

Everyone has a different driving driving style. I just dont feel how it accelerates any better at 2800 rpm than 2200 rpm. The stock TC just seems to absorb too much power.

Many times what I do is I turn OD-off when launching from a stop. Then at ~37mph the TC locks, pulls rpm down, and you get solid transfer of power to the rear wheels without reducing the rate of acceleration.
It helps to slightly lift the throttle at 37-38mph to get a solid TC lock but even with a hot tune its hard to induce shudder with OD-off.

edit:
I see that you are also using the Dodge Ram TCM which probably changes the shift points. Dont know how turning OD-off will effect your shifting and rpms.

How many people have hit 4000 rpm's, and how many times.

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