Optimized Tune For 2016 JEEP WRANGLER 3.6

[Johan Swift]

I'm new to the HP Tuner environment and have only recently started playing around with both PCM and TCM tunes. Does anyone perhaps have optimized settings for the VVT intake and exhaust cams? Looking to get more midrange torque out of it. Also, if you know of any tweaks that could make a huge difference in engine and NAG1 transmission performance or behavior, I will really appreciate it. I know this type of information is normally not freely shared in forums like this, but any help will really be appreciated!

I had to remove the cats due to water damage and I have also fitted a freeflo exhaust. Rear O2 sensors have been disabled.

Thank you in advance.

[LilSick]

Does anyone perhaps have optimized settings for the VVT intake and exhaust cams?

Also, if you know of any tweaks that could make a huge difference in engine and NAG1 transmission performance

I know this type of information is normally not freely shared in forums like this, but any help will really be appreciated!

since you are "new" and "Looking to get more midrange torque out of it." i recommend that you pay someone to help you remotely tune your jeep

me perhaps?

or you can post your file and let whoever do whatever and hope for the best

maximum midrange torque comes from the right spark timing for the right cam timing for whatever fuel you have in your tank

[LilSick]

my email is at the bottom of my signature

[Johan Swift]

I have no problem paying for a good tune and from what I have seen on this forum, there seems to be quite a few experts that have a good understanding of the 3.6 Pentastar and NAG1 transmission in general.

I have recently paid quite a bit of money for a company that advertised on their website and social media to have really sorted the 3.6 tune and problematic shifting of the NAG 1 transmission, claiming significant performance gains. The first tune I was sent to do a log file from was horrific with changes in spark timing that makes no sense at all! I am struggling to get any further tunes from him, so I'm a bit cautious going forward. I would really like to work with someone that has good experience of the HP Tuner software, the 3.6 Pentastar and NAG1 transmission - someone who has actually tuned them before with good results.

I have a 2016 JEEP WRANGLER RUBICON JKU that I have modified as follows:

- Fitted 37" Mud Terrain tyres with 4" suspension lift
- Axel Ratios changed to 4.88 from the stock 4.1
- Catalytic converters removed due to water damage. Here in South Africa emissions compliance is not tested or enforced.
- Free flo exhaust fitted keeping to the stock pipe diameter throughout and retaining the loop after the left side exhaust manifold.
- Fitted a snorkel (mainly for cold air intake)
- Aftermarket thicker core aluminum radiator
- Many other aftermarket accessories not directly performance related such as winch, bumpers, fenders etc.
- Unlocked GPEC2 PCM from HP Tuners, together with a MPVI3


I have a few issues I would like to resolve:

1. NAG 1 shifting behavior. Firstly it relates to the 3rd gear hanging at high rpm before upshifting to 4th when driving up a slight incline. Secondly, when pulling away in first going around a bend, the upshift point to 2nd is significantly increased. Third issue is that I would like all gears to upshift faster (at lower rpms), as my driving style is more relaxed. Fourth one is the upshift points when in 4wd LO - would like them to be much lower (quicker). I cannot seem to be able to change them independently from 2wd Hi. I have played around a bit with NAG 1 and have already made some good progress, but the first, and second points don't seem to change much.

2. After removing the cats, I now experience a random problematic start-up issue that involves a long cranking cycle, as if fuel supply is problematic. If i then depress the accelerator pedal, the engine would start. I have since discovered that this happens when there is a distinct smell of fuel coming from the snorkel prior to starting the engine. I suspect it might have to do with the valve overlap, with unburnt fumes slowly finding its way back into the intake manifold, flooding it with fuel-rich air. This does not happen on cold starts in the morning and also not immediately after shutting down the engine. It normally happens half an hour or longer after a warm shutdown.

3. I would like the transmission to stay in gear when manually shifting gears and not upshift when in WOT.

4. In general, improve VVT and spark timing to maximize especially mid-range torque and perhaps improve fuel economy.

I would really like to work with a tuner that has actually achieved good results with this engine and gearbox combination and will pay for a good tune.

[LilSick]

far as a tune i would not touch that with a ten foot pole

but i will tell ya that you should use 6.38 ratio differentials to make up for the added roll out (not to mention the weight) of those 37's

stock tire did not have 85 inches of rollout...

37's are over 115, closer to 120

[Johan Swift]

Stock size is 32". The 4.88 gear ratios and 37" brings it in line with stock gearing. It does just fine to be quite honest, but any additional torque would always be welcome.

I have sent you an email.

[Johan Swift]

far as a tune i would not touch that with a ten foot pole

It seemed like you were offering your tuning services, so I sent you my tune via email. If I misunderstood, then please ignore.

[Stoopalini]

Reach out to Dave, as he's really good with this platform. He is on this site but rarely visits due to his day job and general busy life ... but you can find his info here:

https://www.jeepgladiatorforum.com/f...support.53756/

[HaasExp]

I have no problem paying for a good tune and from what I have seen on this forum, there seems to be quite a few experts that have a good understanding of the 3.6 Pentastar and NAG1 transmission in general.

I have recently paid quite a bit of money for a company that advertised on their website and social media to have really sorted the 3.6 tune and problematic shifting of the NAG 1 transmission, claiming significant performance gains. The first tune I was sent to do a log file from was horrific with changes in spark timing that makes no sense at all! I am struggling to get any further tunes from him, so I'm a bit cautious going forward. I would really like to work with someone that has good experience of the HP Tuner software, the 3.6 Pentastar and NAG1 transmission - someone who has actually tuned them before with good results.

I have a 2016 JEEP WRANGLER RUBICON JKU that I have modified as follows:

- Fitted 37" Mud Terrain tyres with 4" suspension lift
- Axel Ratios changed to 4.88 from the stock 4.1
- Catalytic converters removed due to water damage. Here in South Africa emissions compliance is not tested or enforced.
- Free flo exhaust fitted keeping to the stock pipe diameter throughout and retaining the loop after the left side exhaust manifold.
- Fitted a snorkel (mainly for cold air intake)
- Aftermarket thicker core aluminum radiator
- Many other aftermarket accessories not directly performance related such as winch, bumpers, fenders etc.
- Unlocked GPEC2 PCM from HP Tuners, together with a MPVI3


I have a few issues I would like to resolve:

1. NAG 1 shifting behavior. Firstly it relates to the 3rd gear hanging at high rpm before upshifting to 4th when driving up a slight incline. Secondly, when pulling away in first going around a bend, the upshift point to 2nd is significantly increased. Third issue is that I would like all gears to upshift faster (at lower rpms), as my driving style is more relaxed. Fourth one is the upshift points when in 4wd LO - would like them to be much lower (quicker). I cannot seem to be able to change them independently from 2wd Hi. I have played around a bit with NAG 1 and have already made some good progress, but the first, and second points don't seem to change much.

2. After removing the cats, I now experience a random problematic start-up issue that involves a long cranking cycle, as if fuel supply is problematic. If i then depress the accelerator pedal, the engine would start. I have since discovered that this happens when there is a distinct smell of fuel coming from the snorkel prior to starting the engine. I suspect it might have to do with the valve overlap, with unburnt fumes slowly finding its way back into the intake manifold, flooding it with fuel-rich air. This does not happen on cold starts in the morning and also not immediately after shutting down the engine. It normally happens half an hour or longer after a warm shutdown.

3. I would like the transmission to stay in gear when manually shifting gears and not upshift when in WOT.

4. In general, improve VVT and spark timing to maximize especially mid-range torque and perhaps improve fuel economy.

I would really like to work with a tuner that has actually achieved good results with this engine and gearbox combination and will pay for a good tune.

I've had quite a bit of experience with #1.
Here's a rather lengthy thread on it: https://forum.hptuners.com/showthrea...g-Table-Tuning
Long story short: I wasn't able to gain full control over the 3rd gear hang but managed to improve it somewhat.

#2 is this happening on the factory stock tune?

#3 can be tuned to act as a proper "manually" shifted trans eg no upshifts at WOT unless you slap the stick. Will just sit on the rev limiter otherwise.

#4 These do respond quite well to tuning in the midrange. However, the plastic snorkels do tend to restrict them upto (AEV etc). The cross section is quite small where it enters the bonnet/hood.

[Johan Swift]

#2 is this happening on the factory stock tune?

Yes, it happens with the stock tune and I'm not the only one that has this issue. A friend of mine with a 2013 3.6 Jeep Wrangler also has the exact same issue. He also has a snorkel fitted. I think the snorkel has a scavenging effect on the intake manifold due to warm air rising inside the upward section of the snorkel, causing it to draw some exhaust gasses through the valve overlap into the intake manifold. It also explains why it doesn't happen every time - it depends on where the cam position is when you turn off the engine. But this is only my theory - not sure if it is indeed the case.

[HaasExp]

Yes, it happens with the stock tune and I'm not the only one that has this issue. A friend of mine with a 2013 3.6 Jeep Wrangler also has the exact same issue. He also has a snorkel fitted. I think the snorkel has a scavenging effect on the intake manifold due to warm air rising inside the upward section of the snorkel, causing it to draw some exhaust gasses through the valve overlap into the intake manifold. It also explains why it doesn't happen every time - it depends on where the cam position is when you turn off the engine. But this is only my theory - not sure if it is indeed the case.

I daily a sprintex s/c'd 2013 JKUR with a AEV snorkel. Never have experienced this start-up issue. Nor have I experienced it on any other JK 3.6 I've tuned either n/a, s/c'd or turbo'd that have snorkels. Very odd.
Got a datalog of the issue with a wideband o2 sensor as well?

[Elm Street]

Regarding the #2 concern, it might not be the snorkel, but the EVAP purge valve. Shows up especially on fuel fill up. It intermittently sticks open and will cause hard start because fuel vapors flood engine. Just my experience.

[LilSick]

and you are in a country that does not have emissions requirements...

moek

[Johan Swift]

Regarding the #2 concern, it might not be the snorkel, but the EVAP purge valve. Shows up especially on fuel fill up. It intermittently sticks open and will cause hard start because fuel vapors flood engine. Just my experience.

I have blanked off the EVAP Purge valve but the problem persists.

[HaasExp]

I have blanked off the EVAP Purge valve but the problem persists.

Gas tank not pressurizing while warm and standing?

[Johan Swift]

Gas tank not pressurizing while warm and standing?

Probably not impossible, but it never used to be a problem before I removed the CATS. Besides, with the EVAP blanked off I cannot see how this can still be a problem.

[nashjeep]

Bro do you have a tune for 2013 jk manual transmission with sprintex sc and no cats?

[GrannySShifting]

far as a tune i would not touch that with a ten foot pole

Why