Oh yes we did. Our RTI ramp isn't just for Jeeps. Any vehicle that shows the barest hint of off-road potential (or marketing, for that matter) is going to face the music.
This morning I lined-up the 2011 Nissan Juke AWD with the ramp, locked it in AWD and drove it up the incline to an RTI of...
Place your bets.
Incidentally, this photo illustrates why the NSX hasn't visited the ramp, despite your pleas. A certain approach angle -- 20 degrees, in fact -- is the price of admission to this ride.
This is what they call the "all she wrote" point. The Juke's left rear tire said goodbye to the concrete when the left front was 8.75 inches off the ground.
But I was easily able to drive the Juke farther than this without wheelspin thanks to a pair of torque-vectoring clutches in its rear diff. The AWD lock button shunts exactly 50 percent of the total torque to the rear axle, and once there the clutch connected to the tire with the most grip gets the lion's share, up to a full 100 percent of that 50 percent. In short, once the left rear lifted off the Juke's right rear received 50 percent of the engine's total output while the left rear got nada, zip, zilch.
Ergo, the Juke will go beyond the point where it is teetering on three wheels without wheelspin.
But an RTI measurement pertains to suspension articulation, so 8.75 inches is the number we're after.
That amount of lift amounts to a trip of 25.6 inches up the ramp. Dividing that by the Juke's 99.6-inch wheelbase, we arrive at an RTI value of 257.
For reference, our 2012 Jeep Wrangler Sport started off at 561 on stock tires.
I'm thinking of attaching a metal leaderboard to the side of our ramp, with magnetic tags indicating how far each vehicle got. What say you?
Dan Edmunds, Director of Vehicle Testing @ 19,221 miles
greenpony says:
10:31 AM, 01/17/12
Can you, uh, bring the Raptor back for this?
throwback says:
11:26 AM, 01/17/12
Has the Mini met the ramp?
ptcdawg says:
11:41 AM, 01/17/12
I'm going to find a pig and put some lipstick on it. That's how useful I think this is for street rides.
elgac says:
12:06 PM, 01/17/12
Unhook the sway bars and hit it again.
hoops26 says:
12:33 PM, 01/17/12
RTI board = awesome
Is it cheating to back up the ramp versus drive forward? I have an old reg. cab short bed 4x4 Ranger that RTI's WAY better in reverse.
actualsize says:
12:37 PM, 01/17/12
We will, of course, bring a Raptor back in for this.
As for the lipstick-slathered pig comment, I can't disagree. But every list needs a Richard Whiteley on the bottom. And this may not, in fact, be that pig. The search continues.
actualsize says:
12:56 PM, 01/17/12
Now that I think about it, the only trouble with tagging the ramp itself is this: wheelbase comes into play in the RTI calculation, meaning that long wheelbase trucks that go farther up the ramp may not actually do better. It only really works as a visual if all are the same truck, such as our own Jeep as we add mods to it.
We can, however, make a leaderboard that stands nearby.
texases says:
01:31 PM, 01/17/12
I'd trade a dozen RTI posts for a suspension walkaround (911 and NSX next!).
actualsize says:
02:22 PM, 01/17/12
Stay tuned...
fundango says:
02:44 PM, 01/17/12
So the Juke's left rear wheel didn't spin at all once lifted off the ground? If so, Nissan's torque-vectoring system is surprisingly effective.
noburgers says:
05:39 PM, 01/17/12
I wouldn't trade for the suspenension walkarounds but this is pointless fun. The leaderboard reminds me of the Top Gear lap time chart.
BigFordFan150 says:
05:49 PM, 01/17/12
This is cool and unique. Keep it up. Lets get the Explorer up this thing and the Top Gear leaderboard would be cool
miamifan1 says:
07:08 PM, 01/17/12
loving this pointless fun! where else can you find this stuff?
keep it up.
jukiemcjuke says:
01:57 AM, 01/18/12
This test is pretty funny, but it's actually the closest thing to a traction test that I've seen so far. No wheel spin on the slipping (in this case airborne) tire bodes well for the Juke's AWD system. Also, the top photo perfectly illustrates the Juke's near scrape-proof front end design. This little car definitely delivers on the promise of being "urbanproof".
chrisjoplin says:
06:51 AM, 01/18/12
With Subaru and their fans being so confident in their AWD systems I would like to see how they measure up. I know this test is about RTI but the part about wheel spin when only two wheel are in contact with the ground is very interesting also.
Maybe IL could take it a step further and measure car manufactures claims of AWD performance with a dual ramp with rollers or some other contraption. I have seen video online of these kinds of tests but I suspect foul play when I don't trust the source of the information to be un-bias.
dinobot666 says:
08:28 AM, 01/18/12
I'm amazed that your center diff hasn't burnt out yet, due to the fact that you replaced two tires on an AWD vehicle. Man you guys make some really, really questionable tire making decisions.
@chrisjoplin
Those ramp tests you saw on Youtube were conducted by an independent company, but I would like to see an updated version of those same tests with a Subaru with their new CTV. I've heard some people complain on the internet that they have to turn the VDC off on the Outbacks equipped with the CVT to cope with really deep snow conditions, otherwise the car just sits there and won't move.
http://www.youtube.com/watch?v=mRL0J8G_Y6A
stovt001 says:
08:55 AM, 01/18/12
I'd love to see the new Explorer compared to an old one.
elgac says:
09:34 AM, 01/18/12
@dinobot666:
The Juke does not have a center diff.
hybris says:
12:33 PM, 01/18/12
+1000 stovt001
Just make sure its a proper V8 4x4 Explorer.
isend2c says:
04:32 PM, 01/18/12
Love the idea of the leader board... and is this going to become part of the full test for short term cars also? I think it'd be nice to see how much off-road prowess the X3 and such have.
yesistreetrace says:
04:51 PM, 01/18/12
I like this test. A test of awd systems would be really interesting, and appropriately seasoned. I'm sure that like me, we all want to know how all the manufacturer's awd systems stack up against each other.
mce63 says:
09:09 PM, 01/18/12
I have to call this one out. This appears to be the most bogus metric I've seen in a while.
I understand measuring wheel height differential. But distance traveled up a ramp is affected by the angle of the ramp. This is completely independent of the vehicle's performance assuming it can climb up a ramp of a given angle. A steeper angled ramp means less travel up the ramp and a lower score for a given height. Using the ramp angle calculator found on the offroaders dot com website:
Given a car with 100" wheelbase and a raised wheel height of 10"
At a ramp angle of 25 the distance is 23.7 for an RTI score of 237
At a ramp angle of 20 the distance is 29.2 for an RTI score of 292
At a ramp angle of 15 the distance is 38.6 for an RTI score of 386
Lowering the ramp angle improved the performance rating of the same vehicle with the same tire height. Ramp angle scores listed on that site are not qualified by the angle tested.
The use of the wheelbase is dubious as well because a 100" wheelbase car must have a wheel rise to 10" to get the same score as a 90" car with a wheel raised to 9". In the real world, a 10" rock poses the same challenge to either vehicle. Sure it may be harder for the shorter wheelbased vehicle, but you either make it or you don't.
Then there is the problem of using the distance the front wheel travels (hypotenuse) vs. the distance rest of the wheels travel.
It seems the more simple and usable metrics would be wheel height alone or for those who want to compensate for a short wheelbase, the angle of the two wheels to the ground at maximum lift. Tan (angle) = wheel height/wheelbase
I'd be interested in hearing how this is useful in offroading beyond lining up and seeing who has the biggest package.