rickinAZ

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At the same time there have been MANY cases of cars making a lot MORE than advertised HP.

2003 Cobra(390 advertised vs 390WHP), the new Supra (335 advertised but usually make 390WHP easy) , Coyote Mustangs, C8 Corvettes, new 911 Carrera S (442 vs 490+WHP), just to name a few that are well known to make more than advertised. I wouldn't be surprised at all if the 3.0 is making 10%+ more power than advertised, and I don't know why everyone here is taking this so personal.
FCA lost credibility with me when they flooded the advertising a few years back touting a 9.6 second quarter mile for the Demon. No automotive magazines have broken the 10 second mark yet. Usually manufacturers claims are replicable.

The Rubicon 392 is also likely blowing sunshine with their 13.0 second quarter mile claim. All of the publications will test one - wait and see what they end up with.
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40”JLURD

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FCA lost credibility with me when they flooded the advertising a few years back touting a 9.6 second quarter mile for the Demon. No automotive magazines have broken the 10 second mark. Usually manufacturers claims a replicable.

The Rubicon 392 is also likely blowing sunshine with their 13.0 second quarter mile claim. All of the publications will test one - wait and see what they end up with.
The sun shines even on a dog’s ass every once in a while ;)
 

Casey250

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Dynos can vary so much in their reporting its almost impossible to use them as a reference for actual horsepower ask anyone with a dyno and they will explain that dynos are good for using as a reference with installing mods and tuning and measuring gain. You could have two dynos of the same model and get different results, nevermind how different types of dynos are and their results. The dyno I used on my Ecodiesel is known for outputting low numbers. For reference my c7 z06 corvettee manual dynod at 537hp /581 lbft (rated at 650/650 crank) on the same dyno, so its a good comparison as that is a heavily dynod car.
 
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Dynos can vary so much in their reporting its almost impossible to use them as a reference for actual horsepower ask anyone with a dyno and they will explain that dynos are good for using as a reference with installing mods and tuning and measuring gain. You could have two dynos of the same model and get different results, nevermind how different types of dynos are and their results. The dyno I used on my Ecodiesel is known for outputting low numbers. For reference my c7 z06 corvettee manual dynod at 537hp /581 lbft (rated at 650/650 crank) on the same dyno, so its a good comparison as that is a heavily dynod car.
Thanks for chiming in @Casey250 , it’s nice to hear from someone else in this thread who has actually Dyno’d their own 3.0 Diesel Wrangler :please:
 

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I had mine dyno a few months ago at the Weekend on the Edge in Utah. they were only doing horsepower not torque so I have no idea what my torque was but my horsepower come out to be 245 hp where as Casey250 video showed 220hp He got his jeep the first of the year where as I got mine at the later part of this year. So yes there could be a different tune. there also could be that casey250 was done near sea level where as mine was done at 4500 ft above sea level.

An engineer friend that works one torque figures all the time figured my rear wheel torque to be about 428lb-ft. which comes close to what FCA advertises.
 

rickinAZ

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I can see why the bumper would be all scuffed up due to poor transport handling, but WTF happened here?
I had mine dyno a few months ago at the Weekend on the Edge in Utah. they were only doing horsepower not torque so I have no idea what my torque was but my horsepower come out to be 245 hp where as Casey250 video showed 220hp He got his jeep the first of the year where as I got mine at the later part of this year. So yes there could be a different tune. there also could be that casey250 was done near sea level where as mine was done at 4500 ft above sea level.

An engineer friend that works one torque figures all the time figured my rear wheel torque to be about 428lb-ft. which comes close to what FCA advertises.
I believe that the dyno adjusts for elevation. 220bhp versus 245bhp is close enough that I'd chalk it up to variances between dynos.
 
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FCA lost credibility with me when they flooded the advertising a few years back touting a 9.6 second quarter mile for the Demon. No automotive magazines have broken the 10 second mark yet. Usually manufacturers claims are replicable.

The Rubicon 392 is also likely blowing sunshine with their 13.0 second quarter mile claim. All of the publications will test one - wait and see what they end up with.
RE: 392 -- it seems like their claims were closer this time. Either lesson learned or 1/4 mile times just aren't as big of a deal so there's less incentive to bolster it (IMO, probably this more than anything).

It's run 12.9 @ 98 mph. ~1000 feet above sea level. At least one owner did. I haven't seen any others yet. Not fast, not slow. Once I have my 392 XR with the 4.56 gears I'll probably run it for shits. I need to go run my '09 too, might as well do both at the same time. Putting the new 3.0 Whipple on it (2.9's outdated design was slightly undersized for the 427), interested to see what it'll run. Probably still 11's since it's a brick.
 

houseofdiesel

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Newer multi clutch transmissions you will not have anywhere near 20% loss. That would be more like a 1965 FJ40 with a 350/TH350/and any 1960's OE T Case. My 2016 LWN 2.8L Canyon that is rated at 181 hp factory produced 154 rwhp uncorrected on the dyno. That is only a 15% loss and that was with 34" tires. Roughly 3-5 hp per inch in diameter of tires size increased. Which means the loss from crank to wheels on a modern vehicle is nowhere near 20%, especially not on an 8 speed. The 6L50 is now dated trash compared to the tech in the current 8 and 10 speeds and nothing like the transmissions that are offered in modern HD diesels since the Allison and Torqshift. Realistic loss is 10-12% on factory tires.
 
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Newer multi clutch transmissions you will not have anywhere near 20% loss. That would be more like a 1965 FJ40 with a 350/TH350/and any 1960's OE T Case. My 2016 LWN 2.8L Canyon that is rated at 181 hp factory produced 154 rwhp uncorrected on the dyno. That is only a 15% loss and that was with 34" tires. Roughly 3-5 hp per inch in diameter of tires size increased. Which means the loss from crank to wheels on a modern vehicle is nowhere near 20%, especially not on an 8 speed. The 6L50 is now dated trash compared to the tech in the current 8 and 10 speeds and nothing like the transmissions that are offered in modern HD diesels since the Allison and Torqshift. Realistic loss is 10-12% on factory tires.
Probably true, but the transfer case eats up some power as opposed to what a 2WD vehicle with no t-case and the same configuration would.

So wouldn’t that probably bring it closer to at least 15%?
 

houseofdiesel

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Probably true, but the transfer case eats up some power as opposed to what a 2WD vehicle with no t-case and the same configuration would.

So wouldn’t that probably bring it closer to at least 15%?
Nope, Canyon we have is a 4x4 and so are all my comp trucks and SUV.

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Probably true, but the transfer case eats up some power as opposed to what a 2WD vehicle with no t-case and the same configuration would.

So wouldn’t that probably bring it closer to at least 15%?
2011 F250 with H&S tuner. 390+120 tune = 510. 510x.85=433.5 Dyno tested and made 444 rwhp.
444/510=87% so only losing 13%. I'd rather be pleasantly surprised than claim I have a 550 hp truck when I don't. I simply say that I have a 444 rwhp truck. It's cool that my EB has a 375+hp 4.6 SC Terminator but with 42" tires and through a C6 trans it only puts 275 hp to the rear wheels. Be pretty embarrassing to even claim the 375 or 400 hp wince it's ported with bigger injectors and other mods and it performed like the standard 285-hp 3.6-liter V6 in the Jeep. Advantage is that a gas V6 Jeep's would only be putting sub 200 rwhp to the ground with 42" tires.

For example a 1000hp alcohol motor I dyno'd only made 500 rwhp was on 44" Ground Hogs. The motor came out of a 10 second drag car so the numbers were legit at the crank but couldn't translate to the ground. Be happy that with the abundance of torque that our diesels create we will have far less loss than gassers will when going to larger meats. But when stating and discussing dyno and power numbers always be humble and just low ball it. I've cussed out dyno operators for feeding me corrected numbers and trying to claim they weren't.

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