3.6L Pentastar V6 24V VVT Upgraded Engine vs. Current JK Engine

[The Great Grape Ape]

Ya, I'm confused. Is there anything from Jeep on it actually being an upgraded engine other than the start stop feature?

You mean other than calling it the Upgrade in the order sheet when you order one?
Or the change in compression?

I figure they would be all over that in their marketing, but so far... nothing.

Why? How would that marketing go versus the myriad of greatly improved features, how do you sell a 0 hp/tq increase 2 years after the Grand Cherokee and others actually get a tiny power bump from the same engine update?

There’s a lot more to focus on in the launch (including the overall package), with the transmission they have ratios and gears to promote, with the 2.0T they can crow about numbers and hybrid tech, same with the eventual diesel. However, with the PUG on the surface it’s going to seem the same as the previous one to most (hence this very discussion), and any mention of subtleties like VVL, power delivery, weight saving, etc will look like fluff if it doesn’t up power by some empirical number for the average schmoe to point to.

Even if people don’t think there are improvements/changes, that’s fine, that perception doesn’t really change anything, they’ll just be getting minor benefits they attribute to the old design, which really doesn’t matter.

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[DanW]

I'm pretty sure some internal improvements were also to make it work better with ESS. I don't recall the previous gen Pentastar being paired with ESS.

 

[The Great Grape Ape]

I'm pretty sure some internal improvements were also to make it work better with ESS. I don't recall the previous gen Pentastar being paired with ESS.

IIRC it was added to the export market like Europe for late model Jeeps where the law required, but not in N.Am until the update.

 

[Ottawavalleylad]

You mean other than calling it the Upgrade in the order sheet when you order one?
Or the change in compression?


Why? How would that marketing go versus the myriad of greatly improved features, how do you sell a 0 hp/tq increase 2 years after the Grand Cherokee and others actually get a tiny power bump from the same engine update?

There’s a lot more to focus on in the launch (including the overall package), with the transmission they have ratios and gears to promote, with the 2.0T they can crow about numbers and hybrid tech, same with the eventual diesel. However, with the PUG on the surface it’s going to seem the same as the previous one to most (hence this very discussion), and any mention of subtleties like VVL, power delivery, weight saving, etc will look like fluff if it doesn’t up power by some empirical number for the average schmoe to point to.

Even if people don’t think there are improvements/changes, that’s fine, that perception doesn’t really change anything, they’ll just be getting minor benefits they attribute to the old design, which really doesn’t matter.

Interesting, my order sheet only said ESS. Folks I talked to making their living selling these said minor changes were made for ESS, but when asked about an upgraded 3.6l there were crickets. Again, would like to know if there is a source identifying the upgrades. If I hit any sensitivities, my apologies

Regards,
Average schmoe.

 

[Jamesmcga]

I can tell you that with the six speed there’s definitely a difference between the JK and JL.

In my JL, when I hit around 2200 RPM there is a definite change in responsiveness. My JK never had that same feeling.

 

[swyman]

So why is the newer Pentastar Upgrade engine in the JL tuned to produce *exactly* the same peak hp and torque numbers as before?

Wouldn't that have been hard to do even if you wanted to? It's got different compression ratio, cooled EGR, different oil weight...it seems like the numbers would have changed slightly just because reasons.

This had me wondering with my '16 Ram 3500 also because I bought the Aisin transmission which in
'15 numbers were 385hp 865lbft torque and the '16 was 385hp and 900lbft. So hp numbers didn't change but they upped the torque. Just seems one would have a slight affect on the other?

 

[The Great Grape Ape]

Interesting, my order sheet only said ESS. Folks I talked to making their living selling these said minor changes were made for ESS, but when asked about an upgraded 3.6l there were crickets. Again, would like to know if there is a source identifying the upgrades. If I hit any sensitivities, my apologies

Regards,
Average schmoe.

Didn’t see this reply initially, too busy skiing.

Here’s the Press release that addresses the New Wrangler including the specific mention of: “while the 3.6-liter Pentastar V-6 engine is upgraded for 2018.”

http://media.fcanorthamerica.com/newsrelease.do?id=18667&mid=

Again mentioning the focus on low-end torque delivery.

Add to that the specific mention in the spec sheet of the new compression ratio and the lower oil volume.

2017 JK

2018 JL

 

[Rockmaninoff]

Again mentioning the focus on low-end torque delivery.

This is what I found in the page:

"The FCA US 3.6-liter Pentastar V-6 engine delivers 285 horsepower and 260 lb.-ft. of torque and now features Engine Stop-Start (ESS) as standard equipment. It is engineered to provide a broad torque band with a focus on low-end torque – an essential trait needed for extreme off-roading.

An all-new six-speed manual transmission is standard on all Wrangler models equipped with the 3.6-liter Pentastar V-6, and a new-to-Wrangler eight-speed automatic transmission is optional.

Known for its refinement, power, efficiency, and adaptability, there are more than five million 3.6-liter V-6 Pentastar engines on the road today. The 2018 Jeep Wrangler benefits from the popular V-6 engine’s low-range torque, which is needed when out on the trails or whenever the conditions call for it. "​

It doesn't say low end torque is improved in the JL 3.6 and they never said the JK 3.6 low end torque was low or lacking.

The CR and oil capacity differences are clear.

They should have designed a better intake manifold for the torque.

 

[The Great Grape Ape]

It doesn't say low end torque is improved in the JL 3.6 and they never said the JK 3.6 low end torque was low or lacking.

True it’s not mentioned that the torque is improved, just that the design is focused on low-end torque, which was the point of earlier in the thread regarding the maxes, not exclusive to the update. Was addressing 2 issues at the same time, I should’ve made that clearer.

They should have designed a better intake manifold for the torque.

Yeah, supposedly as we discussed elsewhere, that’s a major reason why the Wrangler, and even GC can’t make the RAM numbers on the old & new Pentastar. Though it would’ve been nice to have seen a token boost to the power numbers, not that it would be as noticeable as the transmission changes.

 

[Rockmaninoff]

Yeah, supposedly as we discussed elsewhere, that’s a major reason why the Wrangler, and even GC can’t make the RAM numbers on the old & new Pentastar. Though it would’ve been nice to have seen a token boost to the power numbers, not that it would be as noticeable as the transmission changes.

It's probably easier for manufacturers to strap on a turbo than to tune the intake only to have it improve things in a narrow RPM band or worse, to add a variable intake.

So do the JL Pentastars have EGR? And do they have the water jacket in the head to cool the built in exhaust manifold or is it only the EGR that's cooled... or both?

 

[BillyHW]

It's probably easier for manufacturers to strap on a turbo than to tune the intake only to have it improve things in a narrow RPM band or worse, to add a variable intake.

So do the JL Pentastars have EGR? And do they have the water jacket in the head to cool the built in exhaust manifold or is it only the EGR that's cooled... or both?

I know they have EGR and that the newer one has cooled EGR, but I don't know about the rest.

 

[Rockmaninoff]

I know they have EGR and that the newer one has cooled EGR, but I don't know about the rest.

And which one's in the JL?

 

[BillyHW]

And which one's in the JL?

The newer Pentastar is in the JL.

 

[Rockmaninoff]

The newer Pentastar is in the JL.

Ok... unless there's a JK with non-cooled EGR, it's safe to assume that JL 3.6s all have cooled EGR?

 

[BillyHW]

Ok... unless there's a JK with non-cooled EGR, it's safe to assume that JL 3.6s all have cooled EGR?

JK's have the older Pentastar which I don't believe is cooled. JL's have the newer Pentastar with cooled EGR.

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