Have you ever been using something you’re very used to, something so habitual that the details and specifics of it almost disappear into a cloud of familiarity, but then find yourself suddenly confronted with the strangeness of it? Like when, say, you’re waiting in a doctor’s office and you get hungry so you pull out and assemble your portable pocket jerky-smoker to properly prepare a chunk of mutton, and then you catch a glimpse of your reflection through the smoke of the contraption in the receptionist’s window glass and it all seems wildly peculiar? I just had a situation like that.
It wasn’t my portable jerky-smoker, though, it was my 1990 Nissan Pao, and this happened when I was in an auto part store parking lot topping off my oil. As you yourself may do, I find the easiest way to add oil to my car is by opening the hood, as trying to punch my way through the hood is messy and tends to lead to unwanted body damage, to me and the car.
I opened the hood, and then started thinking about how most cars today open their hoods, and realized that I’m doing it backwards.
The Pao has a forward-hinged hood. A lot of cars of its era did, and these were really common in the ’60s through the 1990s, with, it feels like at least, a pretty good-sized spike in the 1980s.
I think at least some of the initial thinking behind these sorts of forward-opening hoods was that they would be immune to the terror of an improperly-latched hood flying open at speed and smacking into the windshield, causing loss of the ability to see where you are going, which is, of course, bad. This happened to me once on the highway in a Volvo, and it was absolutely no picnic. This reason alone, you’d think, might be enough to justify their existence.
I’ve heard people complain about engine access with forward-opening hoods, but I’ve never really found this to be a big issue.
Plus, some forward-hood-opening cars, like that Saab up there, really drop the hood down and away, and it seems like you’d have access as good to the radiator and other components up front. I mean, it’s not like most modern cars offer all that great access to the accessories and parts at the very front of the engine bay as it is. I guess you can’t lean over from the front of the engine bay, and there are contexts were that could be an issue, but overall? It’s just not that bad.
In some cases, forward-opening hoods seem to give even better access, like in this old Bugeye Sprite: [Ed note: The frame YouTube grabbed for the video preview shows a front-opening hood. I assure you, you’ll see a rear-opener when you click! – Pete]
They sort of look cool, too, especially those like on that Sprite or something like a Dodge Viper where the whole front clip seems to hinge forward.
Forward-opening hoods also offer some under-hood privacy, allowing you to sob and scream without judgment when you drop a socket down a spark plug hole or catch your tongue in a valve spring or something.
There were front trunks that opened this way, too, like on the Renault 8 and 10, and in these cases, I think maybe a rear-hinge is better.
So why are these forward-hinged hoods effectively extinct? Are modern hood latches so good that they’re now just obsolete? Is the engine access actually worse?
Does anyone else miss these sorts of hoods? I’m pretty sure it’s not just me, and I’d like to hear what you think, because I’m nosy.
IIRC, my Saab 900 hood came off reallllly easily from those hinges. Checks youtube because my memory sucks… was right.
https://youtu.be/pJPK-xTbLN0
I’ve owned 4 cars with front opening hoods, I think.
I started my career at a Saab specialist, I’ve done this more than a few times.
I remember doing it when I owned it, but don’t remember what it was for. That was in 2001, and I can’t recall much about that year, LOL.
My first Saab needed clutch and transmission work when I bought it (my father had a well-equipped shop and the skills to guide me through the job) and the guy who sold it to me told me what to do (probably what’s in the video): put a blanket on the roof, open the hood, unhook the windshield washer hose, undo two bolts, get a friend (or relative) to help put the hood upside-down on the blanket, out of the way. Piece of cake.
From a safety perspective I prefer a front hinged hood, and from a maintenance perspective I’d want said front hinged hood to be easy to remove and strong enough to be placed on level ground without deforming.
I helped a friend change a water pump on an 80’s BMW with a forward opening hood, and it was miserable. But on the other hand, I’ve had two C4 Corvettes and the forward opening clamshell hood was awesome. It opens WAY up, and effectively takes the fenders with it, so there’s lots of room to get to the engine.
The episode of Regular Car Reviews where he gushes over the C4’s clamshell hood was palpable. “The wheels are exposed! LIKE AN F1 CAR.”
I always thought that was endlessly cool. But then I think C4 Corvettes are damn cool too.
Yeah its nice to be able to use the front wheels as a stool while you work on it
I would make a distinction between cars whose hoods flip up (my 1988 BMW 325i convertible) and cars whose entire front ends flip up (Jaguar E type.)
I thought one reason for the forward flip on Swedish cars was for snow to slide off the hood.
Side-opening clamshell access panels are best, but how often do you see those these days?
You mean like on a Model T? Or a Duesenberg?
I think Morgans are the only modern cars to have side-opening hoods. And that’s only because Morgans are still built like they were in the 30s.
My 71 Vega (first car) and 71 Triumph TR-6 (first FUN car) both had front hinge hoods, or bonnets as they say. There was a lot of dead space up front on the TR-6 and I don’t remember it being an issue working on it.
Always wanted something where the whole nose flips forward, like a Spitfire.
My Old Man Yells at Cloud related to automobile hoods – where there’s an ugly seam break where the hood meets the front fascia, instead of having the hood integrated into the design and forming the top of the front fascia.
That’s done very intentionally for insurance purposes. Does form a messy shutline on more complex surfaced hoods for sure.
Is that why they changed it? I noticed it happening more and more on modern cars and thought it was a step backwards. I guess insurance doesn’t wanna pay for hoods.
It’s pedestrian impact regulations. Hinging the hood at the front means you need to have the structure under the hood and behind the front clip to support the hood — structure which cannot deflect and absorb energy (or the weight of the hood would deform the hinges, which would not be good).
This is the same reason why the leading edge of the hood has been migrating rearwards in European cars over the past decade, leading to unsightly cut-lines above the fascia — the latching mechanisms have similarly been migrating rearwards (and lower down) in an effort to reduce the injury potential of someone falling on the hood.
I feel like there would be some advantages for a front-opening hood for pedestrian safety, though you might have to mount the hinges in a weird way. Unlike a rear-opening one, you wouldn’t have to worry about the sharp front edge – the front could be more easily designed to push inward without compromising the integrity of the latch. Plus, if the back edge lifts that gives more space between the hard points of the engine and the person getting hit.
You want the back edge to lift, but you don’t want it to break free. At that point it stops contributing to the crumple zone, and/or becomes a loose projectile that can be forced through the windshield. The goal is for the hood to stay in place, while folding predictably in a manor that stops it from jamming into objects or humans at either end.
It is really straightforward to design a hinge assembly that remains 100% attached, but incorporates the geometry to lever upwards as the hood is forced backward in an impact. Rear-hinged hoods have basically always done this, even if it wasn’t intentional..
Modern latches are strong, but they are still not as strong as hinges. Better to position the latch between two “flexible” structures (hood edge and core support) that will deform in unison during a crash, than positioning the latch at the A pillar where it will experience the sheer of the hood and cabin structure moving in opposite directions.
On the practical side, it is better to support the flexible hood along its longest edge. Locating the hinges on the A pillars resists twisting, and maintains clean panel gaps. The lightweight core support only has to provide simple downwards tension.
I guess I’m thinking at least partially of several concepts back when pedestrian safety was getting greater consideration, where a deliberate lift from the back side of the hood was designed in to give that slight cushioning effect.
Definitely. Lots of current cars have this, Honda, Lexus, BMW etc. The feature relies on explosive actuators that hyperextend the hinge mechanism.
My race car is an E30 BMW. The majority of the time the backwards opening hood doesn’t pose any problems, and I can even disconnect the damper which holds it open so the hood can be open completely vertically for more room. The only time it gets in the way is when doing major work like an engine swap, and in that situation a normally opening hood may have to be removed anyway.
On Saabs the hood was designed as part of the crash structure and during an impact the hood has pins which engage with the firewall area.
I wondered how they handled that. With the hood being so large and structurally substantial, Saab would want to be sure it didn’t pop loose in a collision and force its way through the windshield.
Pretty much all cars have hood hooks and pins, at least since the 1990s.
Well I guess it’s notable to me because one time I was racing a Saab 900 and the front of the car received some minor contact damage, after which we could no longer open the hood due to the pins being engaged with the firewall.
The latches are now reliable, so there is no reason to have them hinged at the front. A rear hinge measurably increases access given any set hood angle and fixed front fenders. Few, if any, modern cars attach all or part of the front wings to the hood.
Also, the access improvement isn’t for owners. Lots of cars don’t even have dipsticks. It is for service shops where they may be removing the front fascia, headlights, or other components to perform maintenance. The accessories are often so densely packaged that there isn’t another option.
There is zero benefit to have the hinge at the front for 99% of cars.
A front-hinge hood forces anyone working on the vehicle to lean on or over a painted fender, raising the potential for cosmetic damage.
Leaning in over the radiator isn’t likely to lead to any cosmetic issues, and if one does occur it will not be visible with the hood/bonnet closed.
Not so much with a clamshell design like a Saab 99/900, not at all with a Viper or Triumph Herald-style full tilt frontend, but it would be a very real concern with, say, a 1957 Ford.
Or an 82 Honda Accord.
I think the access argument is because you cannot stand in front and work on something in the front. That seems to be offset in my mind by the generally better angle front hinged hoods seem to have. Less chance of banging your head in there.
I kind of wish the big trucks went to something like this where the whole clip flipped forward so I could actually get to the engine without a step ladder. And of course various parts buried behind hoses and fuse blocks currently.
I imagine the biggest culprit with regard tot eh change is safety and cost related. with Pedestrian Crumple zones and increased used of light weight parts in the front of cars, it most likely requires hood tie in to be at the most structurally sound part of the car, which is likely the A pillars.
I like it on my 1976 Celica. It was extremely cool on my Spitfire, except I had to figure out a full-on methodology to open it by myself. The whole bonnet tipped forward and it required unlatching latches on either side of the car, then grab one side and kind of rocking it up and down until things started opening evenly enough to tip it all forward. Both the Spitfire and my ’91 Corvette offered amazing access to the engine bay and everything around it, tho.
For the last decade European cars have to have space between the top of the engine block and the bottom of the “hood” or bonnet in usual English.
After sacrificing squads of crash dummies, the boffins realised that knees snapped when hit by cars with low front ends.
And that pedestrians hit would either fly into the windscreen and then on to the bonnet, (or over the roof) or fly into the bonnet, which before the new laws, would offer very little protection from the mass of the engine block below.
Led to the present generation of nose heavy designs.
And I expect they were all designed on Catia software from Dassault Systemes which when given the parameters, comes up with exactly the same curves.
It probably does not have a filter for the opening to be the other way round, and so we have what we have.
I use CATIA, I can guarantee you that if I asked my graduate engineers to design something to the same parameters the results would be wildly different.
But all the exterior surfaces are designed in posh styling software, that gives you shit, weird surfaces that are a nightmare to turn in to something you can actually dimension on a drawing. Not that anyone reads drawings these days.
My F Type has a forward hinged hood which confused the emissions tester when I took it in recently (not sure why). I don’t think it makes a difference really versus a front hinged for access. Only annoyance which is more because it’s also a bit of a clamshell is it can quite easily go out of alignment leading to poor panel fit. It is adjustable but a pain nevertheless.
I don’t miss them because I have two.
And one of the cars has a rear hinged trunk, while the other has a front hinged rear hatch.
Other then looking cool I see no benefit except maybe the space saved near the firewall where hinges would normally go can be used for other things.
But it definitely eliminates getting to the engine from the front. Which can be a little inconvenient.
A lot of cars don’t use gas struts but instead use a prop rod to hold up the hood. I suppose if you do this for a front hinged hood the prop will have to go on one of the two open sides and you lose more access since the rod has to cross diagonally to the hood.
Good call. A compound hinge can help solve that, but it’s more work for the owner to lift it up and over into the locked position.
Also, look at the routing of the windshield washer lines on the Pao. It’s excessive 🙂
on my 71 scout the hinge has a lock feature on the passenger side only. This avoids a prop rod, and provides a near vertical hood surface when open, which is nice, but it also requires the entire hood to be opened just a little further to disengage and that is only from the passenger side of the vehicle. Still I kind of prefer it to the Jeep over open onto the windshield setup.
I think it’s longevity and, by proxy, serviceability. Old cars had front-hinged hoods because it was probably easier to build, safer without secondary latches (as you mentioned), and…the car was probably dead before 100k miles 🙂
On a modern longitudinal engine, you’ve got a lot of belts and tensioners to change, usually up front. You also need to protect the paint a bit better than leaning over a fender to do everything.
IMO, the entire front end (fenders, bumpers, hood) should all come up in a single unit like a cab-over truck, that would be awesome. 270 degrees of service!
Modern longitudinal engines, yes, but most car engines are transverse mounted. Forward hinged hoods would make servicing the belts and such much more accessible.
And also getting at those pesky rear plugs, fuel rails, etc.
I’m kind of disappointed that I consider myself and enthusiast and I’ve never owned a car with a backward opening hood. I feel like a fraud.
Now I have to go look through Craigslist for something with southpaw hood…
I’m an enthusiast who’s never owned a vehicle with a manual (but I can drive them), or a front-opening hood, or pop-up headlights. You’re doing fine.
At least I’ve checked ‘wagon’ and ‘brown vehicle’ off the list, though.
I was not aware that Family trucksters from the malaise era were enthusiasts cars. Learn something new every day.
Pretty much any car has its merits if you’re a car enthusiast…otherwise you border on snobbery.
But that was partly a joke about the internet trope that the best enthusiast cars are a Miata or a brown manual diesel wagon.
It’s probably something to do with crash testing, if the hood is mounted to the crash bar, it’s harder to design in a prescribed deformation versus when it’s mounted closest to the cabin, it’s relatively trivial to get it to absorb energy in the way you want and to fold in half.
Yup, this is what I was thinking. In every scenario, you want the hood to buckle predictably in a crash, for the safety of both passengers and pedestrians.
My current BMW has two latches at each front corner, and two hinges at each rear corner. The latches and hinges could be reversed with no impact on crash performance, like my old BMW.
I think it’s just slightly easier service access is important enough to cover the cost of the double action safety latch.
I had a BMW e34 with a forward opening hood and it was a pain in the ass for me. I got access to 2 sides of the engine instead of 3 sides. No benefits in that case, other than looking cool.
My E34 was the first car I ever changed a radiator on. I don’t remember the bonnet/hood getting in the way, which is weird, because it feels like it should.
I’ve had several cars with this design. My 1987 Buick LeSabre, my 1989 Saab 900, and my 1992 Saab 900 convertible.
I’ve always loved that the LeSabre, of all cars, had such an unusual design. That and the drop-in license plate functionality blew my mind.
The problem with them is pulling a motor. It makes it harder.
I don’t know about you but when I’m pulling an engine the first thing I do is just remove to hood. 4 bolts and it’s out of the way. Although if I had that Viper I might reconsider, that assembly is huge.
Back hinged ones gives access to three sides of the engine compartment, front hinged only two.
But with new cars being so fault free and not user serviceable, two should be enough.
My Figaro also has it and I love it! Just makes it a little more special, which it doesn’t need with all the other specialness going on.
I own one obviously, and I wouldn’t say engine access is any better or worse, although the sheer size of the hood makes comparisons tough.
It’s a neat trick at car shows, but the light weight combined with the large surface area makes me a bit nervous to leave it open on windy days.
The Vette people have told me that the ability to sit on top of the front tire while working is a nice plus, but that’s pretty rare. I assume your Viper also has a built-in wheelwell liner like the pic above?
It does not; the tire is exposed when the hood comes up. So I suppose I could sit on it, although I’ve never thought to do so.