Jeep is Putting a 392ci Gen 3 Hemi V8 in a Wrangler!

11/24/2020
10 min read

Jeep is Putting a 392ci Gen 3 Hemi V8 in a Wrangler!

11/24/2020
10 min read

While auto industry pundits seem to have the talking point of the impending all-electric future on an infinite loop right now, it doesn’t seem like the engineers at FCA got the memo. Hot on the heels of the Hellcat-powered pickup that RAM recently unleashed upon the unsuspecting public, Jeep has finally decided to shoehorn a Hemi into the Wrangler. It’s been nearly 40 years since the automaker has offered eight cylinders in their off-road flagship, and this modern Hemi is a far cry from the wheezy 304-cube AMC mill that was once available in the CJ-7.


Bronze exterior accents help the Rubicon 392 stand out from the rest of the Wrangler lineup.


While auto industry pundits seem to have the talking point of the impending all-electric future on an infinite loop right now, it doesn’t seem like the engineers at FCA got the memo. Hot on the heels of the Hellcat-powered pickup that Ram recently unleashed upon the unsuspecting public, Jeep has finally decided to shoehorn a Hemi into the Wrangler. It’s been nearly 40 years since the automaker has offered eight cylinders in their off-road flagship, and this modern Hemi is a far cry from the wheezy 304-cube AMC mill that was once available in the CJ-7.


The lack of V8 availability created void in the market which builders have sought to fill over the years, to varying degrees of success. But with obvious demand for such a combination, many enthusiasts have wondered why Jeep would ostensibly leave money on the table. “For years, Wrangler customers have been asking us when we were going put a V8 in a Wrangler,” explained Jeep’s Brandon Girmus at the debut of the Wrangler Rubicon 392 Concept in Malibu, California earlier this year. “There were a lot of rumors on the forums that we would never be able to do it – that a Hemi wouldn’t physically fit in the engine bay. So we built this Wrangler 392 basically as a proof of concept – yes, we can do it.”


And as it turns out, not only could they do it, they could actually put it into production. Maybe all they needed was a little push; perhaps the introduction of a worthy competitor did the trick? Whatever the case may be, Jeep’s decision to stuff a 6.4-liter V8 has given this off-road machine a massive performance boost. But it’s important to note that the 2021 Jeep Wrangler Rubicon 392 isn’t just a standard Wrangler with a big engine.


Jeep is adamant that the Rubicon 392 is the most capable factory-built Wrangler in history, and that’s a title which cannot be earned by horsepower alone. To keep up with the newfound performance, Jeep has upgraded the frame rails, front upper control arms and cast iron steering knuckles in order to take full advantage of the additional grunt on tap.


The Rubicon 392’s front and rear five-link suspension systems allow it to tower over lesser Wranglers thanks to a factory two-inch lift and the standard 33-inch BFGoodrich all-terrain tires the Jeep is outfitted with, the latter of which are wrapped around unique, beadlock-capable 17-inch wheels. The Wrangler Rubicon 392 also boasts unique suspension geometry and scores a set of specially-tuned Fox aluminum monotube shocks that are designed with speed-sensitive valving to provide a comfortable on-road ride and steady handling in demanding off-road conditions.


The Jeep’s heavy-duty Dana 44 front and rear axles feature a 3.73 final drive ratio and have been beefed up with thicker axle tubes, while the Tru-Lok electronic locking differentials, the two-speed Selec-Trac transfer case (which has a crawl ratio of 48:1), and the electronically disconnect-able front sway bar have made their way over from the standard Wrangler Rubicon.


The Rubicon 392’s unique Hydro-Guide induction system allows water and other debris to be re-directed out of the induction system before it can reach the engine.


All in, the upgrades equate to approach, breakover, and departure angles of 44.5, 22.6 and 37.5 degrees, respectively, while the ground clearance figure is actually half an inch lower than the standard Rubicon at 10.3 inches. The Wrangler Rubicon 392 can also handle water fording up to 32.5 inches deep thanks in part to a specially-developed induction system that can divert up to 15 gallons of water away from the engine per minute. More on that below.


As the Wrangler Rubicon 392’s name implies, the centerpiece of the package is the 6.4-liter, 392 cubic-inch Hemi V8 installed under hood. It delivers 470 horsepower and 470 pound-feet of torque here and is paired with a performance-tuned version of the eight-speed TorqueFlite automatic transmission that offers manual shifting by way of steering wheel-mounted paddle shifters.


As you’d expect, this provides a transformative upgrade in performance: 0-60 MPH takes just 4.5 seconds in the Hemi-powered Wrangler and it’ll do the quarter mile in 13 seconds flat, making this the quickest factory-built Wrangler by a substantial margin.

Cylinder deactivation technology allows the iron block Hemi to deliver better fuel economy during low-load driving situations (such as highway cruising), while the functional hood scoop feeds cooler, denser air into the induction system for better performance. Jeep engineers also wanted to ensure that the Wrangler Rubicon 392 would have a steady supply of air regardless of weather and terrain circumstances, so they’ve outfitted the new performance model with a unique air intake system.


Previous to the Wrangler Rubicon 392, the CJ-7 was the last Wrangler-equivalent Jeep to receive a V8 from the factory.


Dubbed Hydro-Guide, the intake includes a three-level ducting system with a series of drains that includes a one-way drain in the air box that separates out water. And if the hood scoop’s air inlet is blocked by mud, snow, or other debris, a secondary air path within the hood structure can still feed the engine a steady supply.


With pricing expected to land in the mid-$70K range, it should come as no surprise that the Wrangler Rubicon 392’s cabin is just as focused on creature comforts as it is on capability.


The new leather-wrapped steering wheel features the aforementioned aluminum shift paddles – a first for a Wrangler – as well as an aggressive rim section for extra grip and ergonomic comfort, while performance seats offer aggressive upper bolsters to keep front passengers securely in place during the sort of maneuvering this new Jeep is capable of.


While most of the cabin is pretty standard JL stuff, the aluminum shift paddles and unique bronze stitching serve as subtle hints that this is something special.


An 8.4-inch Uconnect touchscreen infotainment display is fitted as standard and – as with other off-road-oriented Jeep models – it features Jeep Off-road Pages, which provides real-time data that includes pitch, roll, altitude, GPS coordinates, and drivetrain power distribution.


Leather interior, steel bumpers, an electrical switch bank, and a pair of safety packages are among the eleven options that are included as standard on the Wrangler Rubicon 392 that would otherwise be optional upgrades with other models, and since all Rubicon 392 models come with a black interior, the options sheet is a bit short. Buyers will, however, have nine exterior colors to choose from – Black, Bright White, Firecracker Red, Granite Crystal Metallic, Punk ’n Metallic, Sarge Green Metallic, Snazzberry Metallic, Sting-Gray Metallic and Billet Silver Metallic – when the Wrangler Rubicon 392 goes on sale in the first quarter of 2021.

You Can Hemi Swap Your Wangler Too!

Whether you're jealous your model year of Wrangler didn't come with a V8 offering, or simply want more power than your inline or V6 engine can deliver, Holley offers gen 3 hemi swap systems specifically for the 1997-2006 Jeep Wrangler! Exhaust, engine mounting, transmission mounting, and engine control (ECU) components are ready and on the shelf to make swapping a V8 into your jeep quick and easy! Click the image to see all of the available swap parts! Click the image to see all of Holley's Wrangler gen 3 Hemi swap systems and Components!

author

253 Posts