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garyji

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Welcome and thanks for the update.

G.
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BCMgunner

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You’re mileage should come up, I’m getting 12.7-12.9mpg on 37” KO2s.
 

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Is the recommendation for engine break in period 300 miles or 500 miles? I have seen both numbers mentioned.
 
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Taanto

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Congrats and great write up. Too bad about the paddle shifters. Looks like the Ram TRX was better implemented from reviews I’ve read so far.

Does the front axle have the Front Axle Disconnect delete on passenger side or is it solid from dif to knuckle?
Congrats and great write up. Too bad about the paddle shifters. Looks like the Ram TRX was better implemented from reviews I’ve read so far.

Does the front axle have the Front Axle Disconnect delete on passenger side or is it solid from dif to knuckle?
20210503_093640.jpg
 
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Taanto

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Is the recommendation for engine break in period 300 miles or 500 miles? I have seen both numbers mentioned.
This is from a chatger forum for the 392, I figured the procedures would be similar enough. Did not flip through the owners manual

0 to 100 miles (0 to 161 km):
• Do not allow the engine to operate at idle for an extended period of time.
• Depress the accelerator pedal slowly and not more than halfway to avoid rapid acceleration.
• Avoid aggressive braking.
• Drive with the engine speed less than 3,500 RPM.
• Maintain vehicle speed below 55 mph (88 km/h) and observe local speed limits.
100 to 300 miles (161 to 483 km):
• Depress the accelerator pedal slowly and not more than halfway to avoid rapid acceleration in lower gears (1st to 3rd gears).
• Avoid aggressive braking.
• Drive with the engine speed less than 5,000 RPM.
• Maintain vehicle speed below 70 mph (112 km/h) and observe local speed limits.
300 to 500 miles (483 to 805 km):
• Exercise the full engine rpm range, shifting manually at higher rpms when possible.
• Do not perform sustained operation with the accelerator pedal at wide open throttle.
• Maintain vehicle speed below 85 mph (136 km/h) and observe local speed limits.
For the first 1500 miles (2414 km):
• Do not participate in track events, sport driving schools, or similar activities during the first 1500 miles (2414 km).
 

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LennyV

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Wow this is great! When mine finally ships I will have a 100 mile drive home. It's going to be tough to stay under 55!

Thanks for sharing!
 
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Taanto

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I heard that premium fuel is REQUIRED not just RECOMMEND. My Mojave runs about 16-17mpg. So I've been keeping track of fuel the past 4 weeks to get an idea what it cost as a daily driver. Thanks for the info.
Yes I would say it is required. I would also say premium fuel is required for just about any performance engine. OEMs can either dumb down their tune or lie and say any octane level in acceptable, that's basically it. Higher octane increases knock resistance, allowing a greater window of "safe" performance levels. The higher the octane, the bigger safety window allowed in the tune/build. Anything that is running aggressive timing or high compression requires high octane.

Once I get around to cracking the owners manual I will see if jeep states a requirement or not.
 
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Taanto

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Now that I'm thinking about it, I suppose it's possible that some OEMs may use octane sensors and be running multiple tunes like a flex fuel setup.
 

ValkyrieFalling

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Congratulations on your purchase! Green is stunning on that vehicle.

I am very interested in learning about how you go about deadening the sound, what products you use for it, etc. When you start the process, I’d appreciate it if you’d give updates on that process.
 
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Taanto

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Congratulations on your purchase! Green is stunning on that vehicle.

I am very interested in learning about how you go about deadening the sound, what products you use for it, etc. When you start the process, I’d appreciate it if you’d give updates on that process.
Yeah no problem, I will probably end up creating another thread. Its basically a tedious process of adding mass, adding material, and decoupling. I will use the Hotheads headliner for sky one touch, about 120 square feet of SoundSkins pro plus mat, some closed cell foam, some spray in acoustic material, tesa tape and a bit of rtv.
 

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Taanto

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So just another update on some things I have noticed...

The exhaust in quiet mode is really quite excellent. There is no drone, it is very tame, and quiets down cabin noise substantially on the highway. With the exhaust open, the car provides a very rewarding experience. It is loud, probably most would think it is too much, but I think it is just right. The exhaust does drone around 2k rpm, made very apparent when scrolling through the gears manually. Aggressive note on gear changes and provides plenty of feedback to know where the engine is at.

I also wanted to point out just how solid this jeep is. This is my 4th jeep, and 2nd wrangler. All of them had creaks and rattles and pops, but this one is silent. No dash rattle, no speaker reverb, no creaky suspension. This is huge for me. I am not sure if I just got a good one or if jeep is putting more effort in to isolating noises, but it is a true joy to not have it sound like my car is made of wood when its cold out.

The sound system is more or less just as good as the Alpine in my Gladiator. The sound stage is somewhat better and the highs aren't as crowded up front. Bass I would say is adequate for most but lacking for me. The planned sound deadening will help with perceived output some. With the windows out and the top back, the subwoofer basically disappears and the heard mids/lows are generated exclusively by the 4" drivers up front. They do a good job with fill but really do not provide any depth to the sound. Since I will have my whole dash out for the deadening I will probably replace the 4 dash speakers while I am in there.

Thats it for now.
 

Cypher

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You’re mileage should come up, I’m getting 12.7-12.9mpg on 37” KO2s.
do the 37s fit with no rubbing etc when flexed?
 

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I get 13 mpg on my 6 speed manual. 35 in BFG KO2 stock gearing. Painfully slow, it see 6500 rpm all the time, just painfully slow. I wish they fill 392 orders faster.......

Jeep Wrangler JL Got a 392, ask away. b182665684d8858082f361f61d6f633
 

supermike

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Now that I'm thinking about it, I suppose it's possible that some OEMs may use octane sensors and be running multiple tunes like a flex fuel setup.
they may not have sensor for octane, but they use knock sensor for the job. when lower grade fuel is used, a detonation, Knock or Pinging will occur, ECM retard the timing and trim for fuel, thus less power.
 

Rob97RR

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Hey everybody,

I just picked up my 392 and wanted to make myself available if anybody wants any questions answered. I have backgrounds in mechanical and audio. I'm not quite yet at 200 miles and I plan on properly breaking the 392 in, so no track times or performance date yet.

Here's a few things to get us started. The power delivery is a riot, on the jeep suspension it flexes hard at any amount of decent throttle. The ride is softer and more forgiving on the road than my JT or my JK, by far. It is incredible smooth. The seat bolsters are indistinguishable from my JT rubi, in terms of comfort or feel. The paddle shifters are basically novelty only, shift times are in excess of 1 full second. They remind me of the shifters in a CVT civic. They do not allow gear jumps either, i.e. 8th to 6th. It cycles through each gear slowly. That said, I am not going over 4500rpm or half throttle right now, so maybe they come alive under higher pressure.

The exhaust button is awesome and it remembers your last setting. Want to quiet down before coming in to the neighborhood? Your 392 remembers that in the morning. However, as others have stated, cold start is always loud for atleast 3 seconds. The initial rap of it starting is quite satisfying. The idle on this car is also very satisfying. The rhythmic rubrubrubrub is reminiscent of some deliberate cam lope or idle overlap, but not quite. In quiet mode the exhaust is remarkably quiet. Under 2k rpm it is as loud as my JT was. In quiet mode the exhaust will open automatically if you give it some gas.

No auto start auto stop. Backup camera is dog. This is my first sky one touch and it is great. Far quieter than I though and completely acceptable K02 noise levels. Runs about 2db higher than my hardtop JT. Full sound deadening, spray in and mat coming soon if anybody is interested.

That's all for now but if you guys want measurements or pictures or whatever, just ask. Have a good rest of the weekend!
A couple comments/questions:

First: I agree with everyone else, love the Sarge Green! It definitely wears the bronze accents better than all the other colors. :like:

Second: Keep us posted if the paddle shifters start to feel more responsive with mileage, and/or increased RPM or throttle pressure.

Third: What didn't you like about the rear camera? Do you also have the off-road trail camera option? I've heard that you get a different rear camera with that package, so I'm curious if the performance is different as well.

And Finally: Given your background, you may be able to answer a random question I have about the stereo performance.

There was a thread in the general forum a few months back, where a guy mentioned that he and his wife, or girlfriend, both owned similar JL's, and both had the same factory stereo upgrade option, and they both also had hard tops. Yet, he said the same stereo sounded quite a bit better in hers than it did in his. The only thing he mentioned that was different between the two was that his had the hardtop headliner. So my question is this: I also ordered mine with the hardtop headliner, so I'm curious if you think that this could in fact have been making a significant difference, and if so, would removing the headliner really make the performance of the stereo noticeably better, and even if it did, would it also greatly increase the level of road noise/tire noise.

(I don't even know if liner removal is even possible, so I guess I'm just asking hypothetically.)

Thanks for your time,
-Rob
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