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TESTED: 2021 Jeep Wrangler Unlimited Rubicon 392 - How Fast Is the Wrangler V8?

This is what happens when you stick a 470-hp V8 in a Jeep

  • Faster than it should be, the Hemi-powered Wrangler Rubicon 392 is exciting and terrifying all at once
  • Sudden stops aren't really its thing
  • On-road handling that will put you in a ditch and off-road capability that will get you out of it

The idea of stuffing a V8 engine into a Jeep Wrangler isn't a new one. In fact, it's not even new from a factory equipment standpoint, as AMC, way back in 1972, stuffed its 304-cubic-inch V8 under the hood of a CJ-5 Renegade. And shade tree mechanics have been dropping one V8 or another in between the fenders of Jeeps since we don't even know when.

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But Jeep is friends with Dodge, and Dodge has these 392 Hemi engines just lying around and … yeah. It was only a matter of time before a snarling Stellantis 6.4-liter V8 wound up under a Wrangler's hood, which brings us to the 2021 Jeep Wrangler Unlimited Rubicon 392. We knew it was going to be fast, but we didn't think it was going to be quite so hilarious. And scary.

2021 Jeep Wrangler Unlimited Rubicon 392

2021 Jeep Wrangler Unlimited Rubicon 392

A rocket-propelled cinder block

We'll start by saying that the four-door-only (hence the "Unlimited" part) Jeep Wrangler Rubicon 392 has a speed limiter at 100.5 mph. We know this because our Jeep 392 smacked right into said limiter in well under 13 seconds of full-throttle acceleration at our test track. And it rode that speed limiter right through the quarter-mile, which passes in 13.3 seconds. That's not bad for a sport sedan, but this is a Jeep Wrangler.

Rewinding those 13.3 seconds, the Rubicon 392 nearly lifts its left front wheel in the air as it launches to 60 in 4.7 seconds (4.3 seconds if you use 1-foot of rollout like some other publications do). There's no launch control in the Rubicon 392, so we power-braked it to about 3,300 rpm and let it rip. Is there wheelspin? Yes. Is it loud? Yes. And it's fast enough that you could probably dust off that annoying Charger bro sitting next to you at the light. You know, the one with the yellow splitter guards.

2021 Jeep Wrangler Unlimited Rubicon 392

2021 Jeep Wrangler Unlimited Rubicon 392

You'll stop. Just not now. Or now. Or now.

It's a bit unfair to judge what is essentially a purpose-built off-roader by normal braking standards. But since you gotta drive it on-road to get somewhere off-road, it's nice to know you can stop hard if you need to, which proved to be a challenge in our 392 Wrangler. The shortest distance we recorded during our panic stops from 60 mph was 143.6 feet. That's long. That's longer than a 7,000-pound-heavy-duty-pickup-truck long. We put the blame where the rubber meets the road. The BFGoodrich Baja Champion All-Terrain T/A KO2 tires just don't have the grip to stop this Jeep quickly.

Braking stability isn't so hot either. Again, that's got something to do with the aggressive off-road nature of the tires, but the Jeep's already vague steering and loose suspension make the Rubicon 392 feel like it's wandering around all the way down to a stop. The brake pedal is another disappointment — it's just too soft, with too much travel and no feel to speak of. This is a bit of a missed opportunity for Jeep since it could have probably fitted Hellcat brakes and charged another couple of grand without buyers batting an eye.

2021 Jeep Wrangler Unlimited Rubicon 392

2021 Jeep Wrangler Unlimited Rubicon 392

Moab? No problem. Mulholland? Not so much.

Again, the Rubicon 392 is essentially an off-roader first and an on-road vehicle fifth. Even with the improvements made to this newest JL generation, the Jeep's steering is vague at best. When you put it on a skidpad, that steering and those aforementioned BFGoodrich KO2 tires conspire to do the bare minimum on asphalt. After much sawing at the wheel, we registered a scant 0.72 of lateral g on our skidpad. That's a higher number than we recorded for the new Chevy Tahoe (0.70 g) and the Mercedes-Benz G-Class (a hilarious 0.62 g) but those vehicles were limited by overly cautious ESC (electronic stability control) that keeps things from getting too out of hand.

The 392 Wrangler, on the other hand, lets you turn everything off, which is cool until you punch the throttle and then remember that you can't really stop hard and won't have the grip to make the turn anyway. Even during our acceleration runs, the Jeep displayed a willingness to wander and weave with no steering input. Again, it might seem unfair to be critical of this Jeep for not handling well in an unnatural habitat, but this is 2021 and we do expect even a hard-core off-roader like the Rubicon to be less sloppy and spooky when you lean on it. Especially when you jam it with a 470-horsepower V8 engine.

Edmunds says

If you stick to what the Jeep Wrangler Unlimited Rubicon 392 does best, it's a riot. Is it for everyone? Absolutely not. But it's a unique and thrilling experience, especially with that ripping V8 soundtrack. If you can keep your right foot in check, at least until you get off the road, the Rubicon 392 will deliver more fun than you'll know what to do with.

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