Ariel Nomad - possible idea for Exocet variant?

This looks very cool...

http://www.roadandtrack.com/new-cars/future-cars/news/a24611/ariel-is-going-to-build-the-atom-of-dune-buggies

I say that it's very cool, but few will want to shell out $45k for a Honda-powered dune buggy. One thing that always concerns me with a design like this is how does one keep the unsprung weight in check? Those big ol' wheel/tire combos might work well on a 4000 lb. SUV, but how's a 1700 lb. car going to ride and handle with 100 unsprung lbs. sitting at each corner?

It looks cool, hope its got plenty of wheel travel. If you can't make it street legal though, that will hurt sales. 45K does seem really pricey.

Man I like that

I've thought about doing something very similar - talked about it on the forum a few times over the years. I love Class 1 buggies but they're big heavy bruisers. Could you do a lighter, smaller version? The rise of the high performance UTV is approaching my concept from the low side. Basically, something that uses commonly available uprights (you can guess what from) and a light four cylinder drivetrain with lots of wheel travel. Class 10 buggies are close but usually single seaters. I'd probably use a transverse FWD drivetrain in the rear. BTW, a Class 10 usually runs about 2000 lbs. Using the Kit Car Weight Correction Factor of 15%, the Nomad should run about 1700 lbs with no protection from debris.

A new Atom (which is pretty difficult to register in the US anyhow) starts at $65k. FYI.

At Ariel's prices, anything they make is a good idea for an Exocet variant

I don't see this being a viable product for them. When they came outt with the atom, it looked different than anything else out there, and the power to weight ratio was off the charts compared to anything comparable.

neither of those is true with the dune buggy world, it looks pretty much like any other dune buggy, and they are very very underpowered compared to top of hte line dune buggies.

Kreb, you know I'm ignorant of unsprung weight and how it kills handling.

would this affect be minimized with the massive travel a dune buggy has? I think the 2 - 2.5 feet of travel at each corner would make this not as big of an issue.

This isn't the first lightweight buggy with relatively high unsprung weight, travel does help reduce the problem (so that you don't have a big heavy axle crashing into the bump stops with speed), and going fast offroad isn't about maintaining a perfect contact patch and good geometry anyway. It's about soaking up big bumps at high speed.

Well, I think the mass appeal here would be if you can use it for off-road fun that could be driven from your house, TO the off-road fun spot! I would shell out for this. I don't have a truck or trailer, and when I did have that stuff to load up my dune buggy and my dirt bikes, it was SUUUUCH a hassle. This way, I could hop in, drive to my "fun spot" tear it up, and drive home. Its like a jeep without the "brickness"

I think i would own an exocet if it had 14" of wheel travel.

icaneat50eggs wrote: Kreb, you know I'm ignorant of unsprung weight and how it kills handling. would this affect be minimized with the massive travel a dune buggy has? I think the 2 - 2.5 feet of travel at each corner would make this not as big of an issue.

Well I'm pretty ignorant about this sort of vehicle myself. That said, If you look at the serious off-road racers and buggies, a common design feature is the really long a-arms. It looks like the long arms are both necessary for long travel, and the geometry would seem to minimize the inertial effect of high unsprung weights. If you've got 20 inches of travel at the wheels, but the coilover is way closer to the center of the car, it may only see 1/5 of that movement. So the unsettling effect of any bumps and the associated unsprung weight would be greatly diminished. On a street car by contrast, the ratio of wheel movement to shock travel may be only 1.2 to 1 and as a consequence any bump energy is transmitted much more into the chassis.

Or so goes my logic. Please correct me if I'm full of pucky.

that's what I was thinking. all my friends that have serious buggies the a arms are mounted 6" apart in the center and are 3 feet long or so,

What about making a standard Exocet with different wheels/tires and shock/spring combos for the on road and off road duty?

How is the Atom still being sold in a universe where people can buy an Exocet? For the price of an Atom, I could have a LS7 powered Exocet and a Miata powered version as a tender.

singleslammer wrote: What about making a standard Exocet with different wheels/tires and shock/spring combos for the on road and off road duty?

I don't see this working well. How much ground clearance could you get? You'd want to run way bigger tires that would hack your gearing all up.

Short arms run into angular constraints sooner than long arms. This limits your ultimate travel. The Miata suspension under the Exocet is limited to about 7" or so.

This is kind of interesting. It's a picture dating to 2006, and I think that it's an Atom. If so, they've been sitting on the buggy idea for quite some time. Notice the similarity between the old and the new?

2006:http://www.locostusa.com/forums/viewtopic.php?t=467

2014:

In reply to icaneat50eggs:

So run a t56 with a 5.3l and a low rear. Use first as a granny low only when fitted with oversized rubber. Running a set of 31s would add 4" of clearance and would get you to a little over 8" total. Not bad. The issue Keith pointed out would be harder to correct.

Have you seen what some of those guys spend on sandrails? $45,000 is not unreasonable.

In reply to Appleseed:

10 large on a transmission is common in that crowd. Also, remember that Ariel is British. They don't have our deserts, but they love getting muddy in the hills and dales.

Hopefully they've put some reinforcement in the floor. An Atom basically has a thin plastic bucket bench seat and not much else between those outer rails.

kreb wrote:

icaneat50eggs wrote: Kreb, you know I'm ignorant of unsprung weight and how it kills handling. would this affect be minimized with the massive travel a dune buggy has? I think the 2 - 2.5 feet of travel at each corner would make this not as big of an issue.

Well I'm pretty ignorant about this sort of vehicle myself. That said, If you look at the serious off-road racers and buggies, a common design feature is the really long a-arms. It looks like the long arms are both necessary for long travel, and the geometry would seem to minimize the inertial effect of high unsprung weights. If you've got 20 inches of travel at the wheels, but the coilover is way closer to the center of the car, it may only see 1/5 of that movement. So the unsettling effect of any bumps and the associated unsprung weight would be greatly diminished. On a street car by contrast, the ratio of wheel movement to shock travel may be only 1.2 to 1 and as a consequence any bump energy is transmitted much more into the chassis. Or so goes my logic. Please correct me if I'm full of pucky.

My understanding is that buggies that run long control arms do so primarily to decrease bump steer.