3.0L Diesel Dyno

[GtX]

Rubileon,

You seem to be arguing for something that occurs very infrequently; maintain a Wrangler in the upper 1/3 of the RPM band. Do you sustain your 3.6 at 4000+ RPM often and for prolonged periods of time where your argument may have merit?

I think most of us who have an order in for a diesel have done so for range and torque at low RPM.

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[AnnDee4444]

I've had this thought floating around my head for a while now, and figured this might be a good spot to post it. I'm certain someone will tell me I'm stupid, but here it goes anyway. Most (car) people know that horsepower can be defined by the following formula: (torque*RPM)/5252. What I realized was that the '/5252' portion of the formula is just there to convert actual units of measurements (ft-lb*RPMs) to an estimated number of average horses. In my opinion the '/5252' is an archaic conversion that is no longer needed, other than to get numbers on the graph to be in the same general scale. The 'torque*RPM' is the important part of the equation (a.k.a. Work or Power).

With this in mind, 2 'P' (that's horsepower without the horse) could be obtained by either 1 lb-ft of torque & 2 RPM, or 2 lb-ft of torque & 1 RPM. Gearing could make those exactly identical speed and torque (ignoring gearing losses).

Torque and RPM alone are not what counts, it is the combination of the two (as long as the gearing can compensate). Obviously there are other factors that come into play in the real world, such as not wanting to operating at max RPM or excessive gearing, etc.

 

[beaups]

I've had this thought floating around my head for a while now, and figured this might be a good spot to post it. I'm certain someone will tell me I'm stupid, but here it goes anyway. Most (car) people know that horsepower can be defined by the following formula: (torque*RPM)/5252. What I realized was that the '/5252' portion of the formula is just there to convert actual units of measurements (ft-lb*RPMs) to an estimated number of average horses. In my opinion the '/5252' is an archaic conversion that is no longer needed, other than to get numbers on the graph to be in the same general scale. The 'torque*RPM' is the important part of the equation (a.k.a. Work or Power).

With this in mind, 2 'P' (that's horsepower without the horse) could be obtained by either 1 lb-ft of torque & 2 RPM, or 2 lb-ft of torque & 1 RPM. Gearing could make those exactly identical speed and torque (ignoring gearing losses).

Torque and RPM alone are not what counts, it is the combination of the two (as long as the gearing can compensate). Obviously there are other factors that come into play in the real world, such as not wanting to operating at max RPM or excessive gearing, etc.

Yes, I think the point you are trying to make is that horsepower is all that matters. And that is true. Torque becomes a useful comparison since it's generally indicative of how much relative horsepower is available at low rpms.

In 2 identical vehicles, the vehicle making the most horsepower at any given instant wins. In the case of the 3.6 or 3.0, the 3.0 wins until the 3.6 is near the top of it's RPM range. Probably a little broader than that range considering the weight advantage of the 3.6. In a drag race, that would mean the 3.6 wins from about 20mph on, since both vehicles will be able to be in their optimum rpm range. In the real world, the 3.0 will likely be more responsive/quicker in every situation other than WOT with a downshift.

 

[JMatt]

Here's what I said:

1. The diesel V6's torque drops during the last 37.5% of the RPM range by around 50%.

The diesel's torque drops ZERO percent during the relevant RPM range. The chart's range is irrelevant. If the chart ran to 10,000 rpm, both engines would drop like rocks by the end. You're making up the range. I earlier demonstrated the diesel can stay between 1700 and 2800 for it's entire operating range, from rock crawling through 100mph. So zero percent.

And I think I figured it out - you're in Australia. You're looking at the chart upside down.

 

[LLANERO]

What you feel in power and torque is relative. Look at the super narrow torque band in the diesel. It goes down starting before 3000 rpm and you would feel that in a bad way.

To look at it another way, in the diesel, the torque will only feel good during 62.5% of the RPM band. In the Pentastar it's fun for 75%. That's what you feel when driving... not the numbers measured on a dyno. Plus there's the smoothness and the near orchestral soundtrack of the Pentastar all the way to 6500 RPM that neither the diesels or the I4 has. Diesel? No thanks.

I believe the red line for the diesel is much lower than that of the 3.6.
Also, I would sacrifice smoothness, etc. for offroad performance anyday.
I'm seriously considering trading my 2018 V6 for a 3.0 diesel.

 

[rubileon]

The chart's range is irrelevant.
...
And I think I figured it out - you're in Australia. You're looking at the chart upside down.

So now the dyno chart is no good?
Funny how many times when a person from country B craps themselves in a debate with a person from country A, they blame it on the other guy's country. Godwin's law needs a new page

I believe the red line for the diesel is much lower than that of the 3.6.
Also, I would sacrifice smoothness, etc. for offroad performance anyday.
I'm seriously considering trading my 2018 V6 for a 3.0 diesel.

No don't do it... is that what you were secretly expecting someone to say? Why do you want to announce a personal thing you're going to do unless you have doubts? If the diesel floats your boat, go for it. There are worse things that could go wrong... with a new Wrangler than experiencing expected characteristics of diesels

 

[LLANERO]

So now the dyno chart is no good?
Funny how many times when a person from country B craps themselves in a debate with a person from country A, they blame it on the other guy's country. Godwin's law needs a new page



No don't do it... is that what you were secretly expecting someone to say? Why do you want to announce a personal thing you're going to do unless you have doubts? If the diesel floats your boat, go for it. There are worse things that could go wrong... with a new Wrangler than experiencing expected characteristics of diesels

I have no doubts about how much more I like the diesel over the 3.6.
My doubts come from trading a less-than-2-year-old jeep with some $$ on mods and that has no issues.

 

[JMatt]

553 lb ft, right? The 750 is Nm.

Sorry, yes. You are absolutely correct. We shall limit ourselves to an additional 100 lb-ft.

 

[rubileon]

I have no doubts about how much more I like the diesel over the 3.6.
My doubts come from trading a less-than-2-year-old jeep with some $$ on mods and that has no issues.

What mods have you done?

 

[LLANERO]

What mods have you done?

Just to clarify, this is not a help-me-decide post. My final decision will come after test driving a diesel powered JL
Mods are:
- 4.56 gears
- front limited slip diff
- front dive shaft
- 3.5" lift
- wheels and 37s
- front steel bumper
- winch
- led pods
- switch panel
- rock sliders
- tire carrier reinforcement
- may be more that I don't remember right now.

Some of the mods could be transferred to the new JL, but I would need the stock parts, which I left in Florida when I moved to Virginia.

 

[rubileon]

Just to clarify, this is not a help-me-decide post. My final decision will come after test driving a diesel powered JL
Mods are:
- 4.56 gears
- front limited slip diff
- front dive shaft
- 3.5" lift
- wheels and 37s
- front steel bumper
- winch
- led pods
- switch panel
- rock sliders
- tire carrier reinforcement
- may be more that I don't remember right now.

Some of the mods could be transferred to the new JL, but I would need the stock parts, which I left in Florida when I moved to Virginia.

Well some of those you can easily keep.

 

[Buttercup 3.0]

What you feel in power and torque is relative. Look at the super narrow torque band in the diesel. It goes down starting before 3000 rpm and you would feel that in a bad way.

To look at it another way, in the diesel, the torque will only feel good during 62.5% of the RPM band. In the Pentastar it's fun for 75%. That's what you feel when driving... not the numbers measured on a dyno. Plus there's the smoothness and the near orchestral soundtrack of the Pentastar all the way to 6500 RPM that neither the diesels or the I4 has. Diesel? No thanks.

I have 2 JKs with 3.6l and just got my new JLUR ecodiesel I assure you you can feel the torque from the diesel add my 38s beads and all the stuff I have on my JKs and this Diesel will stomp a whole in my 4 door JK maybe not our 2 door but it has 5.13 gears and will dam near pop a wheelie with the long travel it has.

 

[kosinar]

I have 2 JKs with 3.6l and just got my new JLUR ecodiesel I assure you you can feel the torque ad my 38s beads and all the stuff I have on my JKs and this Diesel will stomp a while in my 4 door JK maybe not our 2 door but it got 5.13 gears and will dam near pop a wheelie with the long travel it has

I am completely lost reading your comment. What you are saying? Is your eco diesel performing better compared to your other jeeps or worse?

 

[Buttercup 3.0]

I am completely lost reading your comment. What you are saying? Is your eco diesel performing better compared to your other jeeps or worse?

Yes I was typing to fast what I’m saying is the diesel performance is far more better than our jeeps with the 3.6l I’ll be able to back that or maybe not after the build is done I’m actually going with 38s on the diesel vs the 37s on our JKs One of the reasons for buying the diesel is because we will be pulling a small RV with a fully built rig I need that extra torque that the 3.6 does not have neither one of my JKs will pull it safely.

 

[kosinar]

Yes I was typing to fast what I’m saying is the diesel performance is far more better than our jeeps with the 3.6l I’ll be able to back that or maybe not after the build is done I’m actually going with 38s on the diesel vs the 37s on our JKs One of the reasons for buying the diesel is because we will be pulling a small RV with a fully built rig I need that extra torque that the 3.6 does not have neither one of my JKs will pull it safely.

OK. Thank you for clarifying. I am waiting for my diesel jeep so I am alert for good or bad indication about its performance. I like your teardrop. How much does it weight?