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I just purchased a used 2017 Jeep Wrangler JK and had some idle and performance issues with it today and took it to the dealer. They found a fuel injector that was bad and then also found this device. A Jet Power Control Module. The dealer removed it and warned that this would void a warranty, but since we just bought it used would not make a big deal of it.

I am just curious what performance it is supposed to improve?
 

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Basically a plug-in tuner. Changes your fuel map and timing curves and so on.

For a stock engine looks like Jet claims you'll pick up 25 HP.
 

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You don't know? These aftermarket companies know every manufacturers engines better than the people who designed the engines to begin with.
Roger that.
25hp from a black box tune on a gas engine ?, not gonna happen
 
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25hp from a black box tune on a gas engine ?, not gonna happen
Probably not on our little 3.6L that is probably stretched to the limit in this application, although nearly all bone stock engines have quite a bit of oomph left in them, relatively speaking. It isn't as if the manufacturers put every individual vehicle on a dyno and work up a custom tune.

The Roe Racing black-box tuner for stock- and near-stock Gen II Vipers was based on my RT/10. I loaned it to Sean for a week since none of his shop cars were anywhere close to stock. From the tune alone I went from 428/455 RWHP/TQ to 500/525 RWHP/TQ, although the tune that went into the retail product was less extreme (been many years but I think they quoted an approximate 50HP gain). Dodge advertised the Gen II Vipers at 450 engine HP across the board and stock drivetrain loss on them is generally about 15% so just 386 RWHP would be considered normal, but wide variances were common. I had a friend with an identical Viper who dyno'd just 390 RWHP and he was pretty irked after seeing my pulls.

But the real benefit of the tune was the remapped curve -- immediate power and flat response to readline. It was a dream on the track. Stock was a slow climb to peak power, then a weird characteristic dip, then back to peak and a gradual drop-off to redline. Stock is a remarkably poor tune. The new map gave me about 325 HP at about only 1700 RPM and peak at only maybe 2500 RPM. I could roast those 335/30s on an upshift at highway speeds.

But I digress -- the point is, throwing a black-box tune on an engine like that can easily get you 25 HP or more all day long. It just depends on what you're working with. But this struggling 3.6L? Nah. Does make me wonder if they did anything with the response curve though. That would potentially do more for butt-dyno feel than a small HP boost. Jet is a well-known name with a long history, I wouldn't just assume it's all BS.

The funny magic-HP-gain claim is K&N. They used to claim "up to" 25 HP. Sean did multiple dyno pulls with 10 or 12 aftermarket air filters. The best result was S&B which consistently showed a whopping 5 HP gain. Most filters reduced power very slightly. Running without any filter (common on the more serious track-only cars) picked up around 11 HP as I recall, meaning "up to 25" is literally impossible.
 
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It's a box filled with snake oil.
 
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Actually I'm even wondering if ALL these modern days Horse Power numbers that manufacturers promise are even real to begin with.

I have driven a few of these never cars and in many cases power just does not feel like promised.

A good example is our Wrangler. This engine supposed to have 285 HP? Hmm, I'm not so sure. Yes, it's power is more than enough for me, I just don't buy the 285 HP figure. To me it feels more like 250 HP at best.

Who knows, just like the diesel emissions specifications scandal, we may soon see a Horse Power specification scandal as well.

...and an MPG specification scandal too.
 

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I know enough about engines to fill a thimble & have enough room for a fat thumb so... to knowledge vehicles are dyno’d in a stationary position....correct? Driving down the road with wind resistance & several other variables could change that 285 hp. Moving a brick through space is a tough task. Imo my Jeep does a great job. It has more power than any vehicle I’ve owned.
 

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Some people spend $300 on a pedal commander just because their too lazy to use their right foot. If you want to feel more power, a regear will actually do more good then most engine mods. Even with engine mods and a tune, a regear will do wonders and make it easier on your drivetrain.
 

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I know enough about engines to fill a thimble & have enough room for a fat thumb so... to knowledge vehicles are dyno’d in a stationary position....correct? Driving down the road with wind resistance & several other variables could change that 285 hp. Moving a brick through space is a tough task. Imo my Jeep does a great job. It has more power than any vehicle I’ve owned.
Horsepower ratings as advertised by manufacturers are brake horsepower as taken directly from the crankshaft on an engine dyno and under exacting conditions. Ratings from a roller dyno will be quite a bit lower due to friction and drag throughout the drivetrain system. Both however are taken in an enclosed environment. Wind resistance and other external forces have no effect whatsoever on horsepower and torque ratings. Even if there was a way to check both while driving down the road it wouldn't come into play. Just so ya know.
 

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100% that box is snake oil. I tune motorcycles and a power commander is way different on a modified high performance engine.

However, the Pentastar is not “stretched to its limit”. There’s plenty of overhead for more power and torque. You just have to pay to get it (supercharger, turbo, etc). But make no mistake, there’s overhead in this engine.


Probably not on our little 3.6L that is probably stretched to the limit in this application, although nearly all bone stock engines have quite a bit of oomph left in them, relatively speaking. It isn't as if the manufacturers put every individual vehicle on a dyno and work up a custom tune.

The Roe Racing black-box tuner for stock- and near-stock Gen II Vipers was based on my RT/10. I loaned it to Sean for a week since none of his shop cars were anywhere close to stock. From the tune alone I went from 428/455 RWHP/TQ to 500/525 RWHP/TQ, although the tune that went into the retail product was less extreme (been many years but I think they quoted an approximate 50HP gain). Dodge advertised the Gen II Vipers at 450 engine HP across the board and stock drivetrain loss on them is generally about 15% so just 386 RWHP would be considered normal, but wide variances were common. I had a friend with an identical Viper who dyno'd just 390 RWHP and he was pretty irked after seeing my pulls.

But the real benefit of the tune was the remapped curve -- immediate power and flat response to readline. It was a dream on the track. Stock was a slow climb to peak power, then a weird characteristic dip, then back to peak and a gradual drop-off to redline. Stock is a remarkably poor tune. The new map gave me about 325 HP at about only 1700 RPM and peak at only maybe 2500 RPM. I could roast those 335/30s on an upshift at highway speeds.

But I digress -- the point is, throwing a black-box tune on an engine like that can easily get you 25 HP or more all day long. It just depends on what you're working with. But this struggling 3.6L? Nah. Does make me wonder if they did anything with the response curve though. That would potentially do more for butt-dyno feel than a small HP boost. Jet is a well-known name with a long history, I wouldn't just assume it's all BS.

The funny magic-HP-gain claim is K&N. They used to claim "up to" 25 HP. Sean did multiple dyno pulls with 10 or 12 aftermarket air filters. The best result was S&B which consistently showed a whopping 5 HP gain. Most filters reduced power very slightly. Running without any filter (common on the more serious track-only cars) picked up around 11 HP as I recall, meaning "up to 25" is literally impossible.
 

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Probably not on our little 3.6L that is probably stretched to the limit in this application, although nearly all bone stock engines have quite a bit of oomph left in them, relatively speaking. It isn't as if the manufacturers put every individual vehicle on a dyno and work up a custom tune.

The Roe Racing black-box tuner for stock- and near-stock Gen II Vipers was based on my RT/10. I loaned it to Sean for a week since none of his shop cars were anywhere close to stock. From the tune alone I went from 428/455 RWHP/TQ to 500/525 RWHP/TQ, although the tune that went into the retail product was less extreme (been many years but I think they quoted an approximate 50HP gain). Dodge advertised the Gen II Vipers at 450 engine HP across the board and stock drivetrain loss on them is generally about 15% so just 386 RWHP would be considered normal, but wide variances were common. I had a friend with an identical Viper who dyno'd just 390 RWHP and he was pretty irked after seeing my pulls.

But the real benefit of the tune was the remapped curve -- immediate power and flat response to readline. It was a dream on the track. Stock was a slow climb to peak power, then a weird characteristic dip, then back to peak and a gradual drop-off to redline. Stock is a remarkably poor tune. The new map gave me about 325 HP at about only 1700 RPM and peak at only maybe 2500 RPM. I could roast those 335/30s on an upshift at highway speeds.

But I digress -- the point is, throwing a black-box tune on an engine like that can easily get you 25 HP or more all day long. It just depends on what you're working with. But this struggling 3.6L? Nah. Does make me wonder if they did anything with the response curve though. That would potentially do more for butt-dyno feel than a small HP boost. Jet is a well-known name with a long history, I wouldn't just assume it's all BS.

The funny magic-HP-gain claim is K&N. They used to claim "up to" 25 HP. Sean did multiple dyno pulls with 10 or 12 aftermarket air filters. The best result was S&B which consistently showed a whopping 5 HP gain. Most filters reduced power very slightly. Running without any filter (common on the more serious track-only cars) picked up around 11 HP as I recall, meaning "up to 25" is literally impossible.
Apples to oranges!
No way, is there 25 hp to be gained, on our anemic 3.6, with a black box tune.
Now, if you wanna go apples to oranges, I have had 500 hp/960 ft lbs on my '08 6.7 CTD with a box tune. ;) I like them apples!!!
Now, if our government wasn't so strict on engine swaps/upgrades, there'd be a "little" electronic Cummins in my JK :whacky:

You sound so confidant. Could be true. Do you know how many stickers come with new? Each sticker is worth at least 4hp. lol
Very confident. I think 2 sticker are in the box, so thats good for a few :drinks:
 
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Some people spend $300 on a pedal commander just because their too lazy to use their right foot. If you want to feel more power, a regear will actually do more good then most engine mods. Even with engine mods and a tune, a regear will do wonders and make it easier on your drivetrain.
I have a pedal commander to de-tune (feel less power) while rock crawling. More throttle control.
 

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One thing to consider that most aren't thinking about is that this 3.6 rated at 285 horsepower is the same basic engine used in the base Challenger that is rated at 305 horsepower. There's 20 difference to begin with. That being said I have no use for any of these plug and play tuners. But as Mcguirev10 mentions, a positive change in power curve can offer a major difference in performance without changing peak horsepower. It's not so much about peak horsepower but how and at what point power is available. Anyone with track experience either understands this or doesn't show well.
 

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One thing to consider that most aren't thinking about is that this 3.6 rated at 285 horsepower is the same basic engine used in the base Challenger that is rated at 305 horsepower. There's 20 difference to begin with. That being said I have no use for any of these plug and play tuners. But as Mcguirev10 mentions, a positive change in power curve can offer a major difference in performance without changing peak horsepower. It's not so much about peak horsepower but how and at what point power is available. Anyone with track experience either understands this or doesn't show well.
My understanding is exhaust and intake account for some of the difference in the peak numbers on the challenger
 

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My understanding is exhaust and intake account for some of the difference in the peak numbers on the challenger
Yes but the basic engine is the same. There also has to be a difference in tuning to accommodate such things and that factory tune is restricted by government set standards. Forget about those standards and build in a top performance tune to match whatever externals you have on a particular engine and you will see a huge difference in what the engine can do and you may even see a small peak horsepower increase but it can't come from a one size fits all black box. At least I don't think it can.
 

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Actually I'm even wondering if ALL these modern days Horse Power numbers that manufacturers promise are even real to begin with.
The real problem with just about every HP figure, OEM or with a tune, is that it's peak HP which is almost meaningless without knowing what the curve looks like. If you make a million HP just a couple ticks before redline, it's not especially useful. Area under the curve over a peak bragging-rights number is the real game-changer.

I know enough about engines to fill a thimble & have enough room for a fat thumb so... to knowledge vehicles are dyno’d in a stationary position....correct? Driving down the road with wind resistance & several other variables could change that 285 hp. Moving a brick through space is a tough task. Imo my Jeep does a great job. It has more power than any vehicle I’ve owned.
HP and torque are just measurements of the engine's ability to do work at a given engine RPM. Wind resistance and similar factors would impact the result of that work, but the engine is still doing the same amount of work. There are many definitions but the easiest to understand is that 1 HP is required to move 550 lbs one foot in one second.

(Oops, looks like Old Syko replied, but I'll leave this anyway, slightly different angle on the explanation.)

As for apples and oranges and the similar replies my post generated: My point was, ALL manufacturers quote an engine power number that is below (often far below) what the engines can do, on average. Marketing plays into it, warranty economics plays into it -- but mainly they want a conservative target that they know every engine rolling off the assembly line can easily and reliably achieve. (And I mean what it can do bone stock, not with blowers or other power-adders... in which case you're likely going to want a custom tune, too.)

It is therefore unreasonable to state a black-box tuner doesn't work unless you've actually dyno tested that specific device. They're widely used, and they typically do work, pure and simple. They don't work as well as a custom tune, of course, but they're a hell of a lot cheaper.

I'm aware the 3.6L is used in other applications with more power, but I'd always assumed the Jeep didn't have much more in common with those than the block...?
 
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