It’s no good trying to be everything to everyone. We all know that instinctively, but I guess nobody told Honda that about 30 years ago. How did they figure that a tall mid-engined AWD automatic 660cc turbocharged kei car was a sound concept? Someone should have said: “Honda-san, with the utmost respect, I think there are at least two or three features too many in there.” Since nobody piped up, we got the UM-4.
First, there is the question of the name. The use of the letter Z, among Japanese carmakers, is split between Nissan and Honda, but Nissan applied it to their Fairlady sports cars in 1969 and never stopped. Honda used it for their 360cc kei cars between 1970 and 1974, but then ditched the name, and pretty soon stopped making kei cars altogether for a little over a decade.
For whatever reason, Honda resurrected the Z nameplate for this pseudo-MPV, but not their other late ‘90s / early ‘00s kei cars (the Today, the Life, the That’s and the Acty/Street truck/van). Because the memory of the original Z360 has remained quite vivid, nobody really took to calling this unrelated Frankencar “Honda Z;” they are universally known as the UM-4.
UM-4 stands for “Underfloor Midship 4WD” – clearly one of the car’s more unorthodox technical features. Except in the world of kei trucks, where this was pretty common: the Honda Acty, the Suzuki Carry and Daihatsu Hijet all used this solution. Honda had pioneered the concept back in the ‘60s in the TN360. Modern (i.e. ‘90s) mid-engined kei trucks were often offered in AWD variants, too. Still, for a non-truck kei vehicle, this layout was unconventional.
This was not a case of Honda merely using a kei truck chassis, slapping 15-in. wheels on it and calling it UM-4, though. Truck chassis had pretty basic suspension, not something that would be acceptable for a regular car. So the UM-4 had its own thing, with MacPherson struts up front and a sophisticated multilink and coil-suspended De Dion axle in the back – similar to the HR-V, albeit scaled down to kei dimensions.
The UM-4 appeared in October 1998 and was marketed as a “Small Super Mover.” Clearly, Honda themselves didn’t really know what it was. The AWD drivetrain, large tyres and high stance made it a natural fit for mountainous terrain, but the car’s relatively heavy body (950kg is a lot for a kei car) meant that the 3-cyl. engine, in standard 51hp spec, was barely sufficient. The 64hp turbo version was almost a requirement, especially since the 4-speed automatic was the only transmission available.
But then, being underpowered was not necessarily unexpected with a kei car. There were a number of other issues with the UM-4 as a concept, starting with interior space utilization. The front seats were fine, but the ones in the rear, located right above the engine, were impossibly cramped for anyone over kindergarten age. Folding those rear seats down to turn the rear into pure cargo space made a lot more sense: there is just enough space to fit two bicycles back there.
Daily life with a UM-4 was no bed of roses, though. According to one former owner, the front seats were way too firm. The suspension, sophisticated though it was, was also noted as being quite stiff, making long-distance trips something of a chore.
According to another former owner, another hindrance to long-distance travel by way of UM-4 was the tendency of the transmission to overheat and slip when driving the car at speeds of 100kph (about 60mph) over a long time. The level of engine noise when driving pedal to the metal, which is often necessary with kei cars, is also very high. To compound everything else, the UM-4 was noted as being quite thirsty, for a car of its class.
Honda realized pretty quickly that they had a dud on their hands with the UM-4. Prices for the turbo version came down a shade in 2000, so virtually all cars sold after that point had the 64hp engine, but the UM-4’s goose was already cooked by this point in time. Production was ended in January 2002; inventory took until the month of August to be liquidated, just weeks shy of the model’s fourth birthday. With about 40,000 units made, the UM-4 was one of Honda’s worst-selling keis of the 660cc era.
It turned out there was a reason why nobody had ever done a mid-engined AWD kei car: it’s a bad idea. Toyota just about managed a mid-engined minivan, but even they had to ultimately concede that placing the engine within the wheelbase made little sense, from a packaging (and servicing) point of view. Honda’s UM-4 demonstrated that sticking an engine amidships works for sports cars and some trucks, but not mini-MPVs.
Related post:
Curbside Classic: 2000 Honda Z UM-4 — Umm … What Is This?, by David Saunders
People went to look at the UM-4 and I guess said UM-No.
Interesting concept, and sort of a mini-er-Lada-Niva vibe. I do wonder how much “frunk” space there is in this since the engine isn’t there. Actually, that just made me realize that I’ve never seen inside the frunk of a Renault 5 Turbo II, how is that trimmed out, I wonder.
Throw a little bit of black cladding at this thing, another inch or two of suspension, 20% more to the pricetag, rename it the WTF-4 and it might well just have been 25 years too early. This one’s a great little find!
The frunk had just a small storage space with it’s own lid, most of the space was taken away by the spare tire and various mechanical bits.
The UM-4 is an interesting concept but I imagine people who really needed off-road capabilities went for a Jimny or a Pajero Mini
What a fascinating concept. I have to wonder, given kei cars’s strict dimensional limits, how Honda managed to make it so heavy. And why.
Had I been in Japan then, I’d likely have bought one for its technical curiosity – and wound up regretting it, like the owners Tatra spoke of.
But kudos to Honda for exploring the outer ranges of kei-dom, even if they did find that some things, while technically possible, just aren’t worth the trouble.
Well, an inline layout requires two crown/pinion setups, whereas a simple transverse FWD requires none. You could get away with lighter C&Ps if it’s part-time AWD. Those generally have a much lighter & cruder rear suspension, too.
Possibly having a front crush-can and a reinforced rear one too for the engine/suspension is the usual reason why ME designs are heavy.
One of Honda’s charms is they are bat-shit contrarian sometimes. It’s a brilliant idea looking for a problem to solve.
VW can thank their lucky stars their ME-transverse Golf proposal got canned in a favour or a FIAT clone.
This was apparently one of the reasons their bigger mainstream cars (the ones sold in the States as Acuras) took such a turn for the bland in the ’90s: The sales organization was ready to riot because the engineers kept giving them fascinating technological exercises that didn’t have any marketable angle and didn’t answer any actual market demands.
That would explain a lot, actually.
Should have got some more intelligent saleswonks, not dumbed-down the engineering.
They still couldn’t sell SH-AWD nor P-AWS on the beaky, overhangy dirge that followed anyway.
I believe that the inline layout would have worked even better with SH-AWD and produced sleeker shapes. They wouldn’t have needed that contrived ‘styling’ as much.
Well, the problem was that the sales organization sometimes felt they were not getting things they definitely needed. A case in point is six-cylinder engines: When other Japanese automakers were proliferating sub-2-liter sixes, Honda R&D came up with … the G-series five. Which was all very clever, but was answering a different question than was asked. People wanted small sixes because they were more refined and more prestigious, and an inline-five was just the wrong tool for the job. Meanwhile, American Honda had been pushing for years for a V-6 Accord, which it took Honda forever to greenlight. Stuff like that was really a fundamental disconnect between the people selling the product and the people designing it, not a matter of the sales wonks not being smart enough.
Such an odd little car. I am glad that it exists but I cannot imagine who this was marketed to. I think its biggest issue is that is does not do anything all that well. Fast? Nope. Excellent fuel economy? Nope. Great off road? Not really. Wild styling? Unique but perhaps not enough.