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Mid Engine Pickup

Use the area under a pickup truck bed for an engine.
 
(+2, -2)
  [vote for,
against]

There is about a foot of space between the bottom of a pickup truck's bed and the bottom of the bodywork. Using a horizontally opposed "boxer" engine would allow the engine to fit under the truck's bed thus lowering the center of gravity, moving the center of gravity towards the center of the truck and decreasing polar moment. The engine would have to be developed specifically for the task, likely requiring a dry sump and separate intake systems for each bank of cylinders. The engine could be very wide and long in this location. The engine could be used as a stressed member so no frame is needed under the bed. Without the engine up front the cab could be lowered to make the truck more aerodynamic and a front "trunk" could be used for secure storage.

Realistically, an engine would be hard to make less than a foot tall, so a slightly higher bed would result. Also, four wheel drive systems would be very hard to implement but increased weight over the rear wheels would greatly improve on modern trucks tendency to loose grip at the rear wheels and fishtail.

BuffMyRadius, Oct 05 2011

No Steal My Idea VoltsWagon
shame on you, you barbarian [WcW, Oct 05 2011]

C292 engine http://www.gurneyfl...ces/engineC292b.jpg
This Mercedes-Benz developed engine ran the intake runners through the head between the intake and exhaust cams making the engine flatter. [BuffMyRadius, Oct 05 2011]

Honda T360 http://www.thetruth...360-pickup-of-1963/
In 1963 Honda built a very small pickup powered by a 360cc, 4-cylinder, 44hp, 9000 rpm redline engine mounted under the bed. Yes, you read that right. [BuffMyRadius, Oct 18 2011]

CounterBalance Pickup http://blog.cardoma...he-counter-balance/
Here some nutter stuck a V8 under the back seats of a truck, in the process creating a vehicle that, while interesting, is ugly as sin. [BuffMyRadius, Oct 18 2011]

Honda Acty http://en.wikipedia.org/wiki/Honda_Acty
Most of the kei trucks are mid-engine [afinehowdoyoudo, Oct 19 2011]

Genset Trailer http://evnut.com/rav_longranger.htm
[goldbb, Oct 28 2011]

[link]






       already proposed this about a year ago.
WcW, Oct 05 2011
  

       Fair enough. The general purpose of my idea is not for a hybrid power train it is just relocating the engine using it as a stressed member. You can have your VW motor too. This concept would compete with modern pickups and would require 8 or 10 cylinders, DOHC, variable valve timing, and at least 4 liter displacement. If I just delete any mention of hybrids am I still stepping on your toes or would you prefer I just pull the idea down?
BuffMyRadius, Oct 05 2011
  

       [BMR] As long as you've got your engine mid-mounted, in front of the drive wheels, you should avoid both mine (directly above the axle on the frame), and [WcW]'s (on the axle), ideas.   

       //separate intake systems for each bank// you wouldn't *have* to, you could put the filter right in the middle in front of the engine.   

       Pickups only suck when they're unloaded.   

       With a mid or rear-engine layout the weight capacity in the bed gets decreased. Not only is the engine there but you'll probably want to move the fuel tank further back (unless you put it in the front compartment). Also not too sure about using the engine as load-bearing structure: if that were possible, why not just decrease the engine weight in the first place.   

       But yeah great idea: engine under the bed behind the cab, and a spacious, lockable storage area in front. Might want to add a light hydraulic lift to the bed making a faux-dump, for easier engine access.
FlyingToaster, Oct 05 2011
  

       Trucks are actually much more difficult to package features in than cars, because the bed eats up half of the available vehicle volume which could otherwise be used to hide things. No way an engine of sufficient torque capacity is going to fit back there, and not worth the rear axle weight penalty, besides.   

       Slightly higher bed would be a bad idea. Most heavy duty class pickups are used for towing purposes. How would you hook up to a trailer?   

       Moving the engine back there would eliminate necessary suspension travel space, unless you want your springs as stiff as a board.
RayfordSteele, Oct 05 2011
  

       There are many reasons why motor vehicles typically have front mounted engines:   

       Manufacturers can use the same engine and powertrain (or slight variations) in a range of vehicles.   

       Crash loads are easier to manage when there is a large, stiff mass between the front bumper and the cabin.   

       Given the high centre of gravity and massive changes in load distribution inherent in a pickup truck, moving the engine mass will only be of any value under a narrow range of conditions.   

       I believe the Bedford Rascal (small pickup / van) has a mid mounted engine. This is done for packaging reasons rather than performance.   

       Dissapointed that this wasn't an idea for a V8 four poster.
Twizz, Oct 05 2011
  

       The (...okay, my) idea is to improve unloaded handling for regular pickups by utilizing the space between the frame rails on the vehicle's underside. Also to provide a locked front 'trunk' for the spare tire, maintenance equipment/supplies, and a regular toolbox which normally have to be shoehorned into the bed of the vehicle or litter the cab. This would maintain some of the crash protection of a front-engined vehicle. The downside is that when the vehicle is fully loaded the CG is further back than usual.
FlyingToaster, Oct 05 2011
  

       I suppose this "sport truck" wouldn't really compete directly with other pickup trucks. Obviously with such a radical repackage the vehicles goals would change.   

       1) Using the engine as a stressed member is very common in motorcycles, dragsters, f1 and indy cars, and some rally cars. While I am aware a pickup truck is an entirely different animal I don't think my idea is still entirely crazy.   

       2) Electromechanical suspension that can be firmed up. Firm up the rear to carry stuff, the entire car to drive it in "sport" mode, or soften everything to go offroad.   

       3) Have subaru make the car. They use boxer engines for everything so a 4 liter flat 8 or 5 liter flat 10 could be thrown around the product lineup. (Twin turbo sport truck WRX STi anyone?) Throw the thing in a super car. I don't care. Flat 10s sound too delicious to not use everywhere.   

       4) Yes, an engine can be made this thin. The entire block on a subaru ej20 is right around 12 inches tall. Cast two of them inline to each other, run a dry sump and move all the ancillaries around. This can't be impossible.   

       5) Resulting engine is 13 inches thick? Move the bed up one inch. Hitch stays where it is. The rear wheels are still completely behind the engine and suspension is unchanged unless we are talking about some crazy long trailing link design.
BuffMyRadius, Oct 05 2011
  

       //5) // You've still to make room for the transmission, but a 4x4 already has 2 bends in it, so you could put it under the seat. Or put the engine partially under the seat.   

       //Bedford Rascal// is a kei-truck, tiny engine. But for a small/medium pickup that's the engine I want, combined with an electric motor to make a hybrid.
FlyingToaster, Oct 05 2011
  

       [FlyingToster] I was thinking something along the lines of a subaru transaxle where the half shafts come out between the clutch (or torque converter) and the actual transmission. I'm not sure if this would put the engine too far back to the point where it actually will interfere with the rear wheels. Maybe an engine with a normal rwd style gearbox with little or no driveshaft would do the trick.
BuffMyRadius, Oct 05 2011
  

       How about mounting your "very flat" engine vertically behind the cab ?   

       Gearbox/centre diff sits directly below, driveshafts run front and rear to differentials in the usual way. Pipework to radiator (front grille), oil cooler, intercooler, A/C condenser runs forward alongside driveshaft, also (presumably) hydraulics for PAS.   

       Cab seats 3 across.   

       Easy access to engine by removing cover from load bed side, and secondary panel inside cab.   

       Something based on the flat-4 liquid cooled Subaru engine might be workable.
8th of 7, Oct 05 2011
  

       //little or no driveshaft// Then you're into a variable length driveshaft. Just sayin'.   

       I'm not sure how I feel about pickups with independent rear suspension, except if you have the whole mess on top of the wheels you'd have hella oversteer when loaded up.
FlyingToaster, Oct 05 2011
  

       IRS would significantly decrease a pickup's load cap due to the risk if side-loading the ball joints. If anybody wants me to cite my source, I'll go dig around in my box of broken 4x4 parts. I love IFS trucks, but ball-joint failure is one of the most common trailside breakdowns in my neck of the woods, because stock ball-joints sometimes can't handle extreme side-loading while supporting the weight of the engine on uneven ground. Now think about a mid-engine truck with IRS and a half-ton of gravel in the bed.
Alterother, Oct 05 2011
  

       But that's just an issue of underspecified components, shirley ? Balljoints can be made arbitrarily strong just by increasing their size and/or thickness of metal, as can their guide rods.   

       Presuming that the tyres are sufficiently inflated to prevent sidewall distortion, there's no reason why a suspension can't be spec'd to take the whole thrust vector of the vehicle and payload on a 45 degree side-slope. Land Rover swivel pin housings (admittedly, massive steel castings on a rigid axle) can take that; double wishbones with CV joints can take the same loading if sufficiently well made, because the load is taken by the wheel bearings (particularly, the inner cone bearing race), hub, and wishbone pivot points.   

       It's not rocket science.
8th of 7, Oct 05 2011
  

       It's not, but there's a good reason GMC (who makes the very finest pickup trucks in the world, bar none) still uses solid rear axles--they're rugged, stable, and easy to repair. The IFS/solid rear arrangement is the current pinnacle of pickup truck suspensions, and as for the squirrely ride with an empty bed, well, that's what sandbags are for.
Alterother, Oct 05 2011
  

       @ [Allto]   

       GMC has been an innovator in the IRS too. the solid rear axle is robust and simple but consider the downsides. The high unsprung weight causes poor rear traction on uneven surfaces and under high load. The solid rear axle is a compromised suspension geometry with no potential for dynamic tire angle camber, caster or toe. Under side load the rear axle escalates overturn rather than fighting it. The solid axle forces the load to be carried high in the air while the pumpkin places a pathetic limit on ground clearance. When high centered on the axle (where else?) the vehicle looses all rear wheel traction. The variable driveline angle wastes energy and fuel and requires additional joints. Suspension motion must be accommodated across the width of the vehicle rather than only over the wheels wasting cargo capacity. While it may still be the load hauling standard for trucks it is not superior to an IRS in any way but cheapness and reliability.
WcW, Oct 05 2011
  

       @ FT seriously what were you smoking?
WcW, Oct 05 2011
  

       ^ Yours is obviously better.   

       IRS isn't going to improve ground clearance by much and that only when empty or lightly loaded. Rollover is increased, and as far as angles are concerned, solid axle uses 1, at the universal; IRS uses what, 2 ? 4 ? and they're greater angles per wheel movement.   

       Smoother though. And less bouncy.
FlyingToaster, Oct 05 2011
  

       [8th of 7]I wouldn't mount the engine vertically behind the cab. My goal is to package a pickup more efficiently. Vertical mounting would require dedicating a space for the engine. Using the area under the bed is utilization of wasted space.   

       [FlyingToaster] Dude, I have no idea what you are talking about. There is no variable length drive shaft anywhere in this.   

       Does anyone know of a vehicle that uses half-shafts, but still a beam suspension? Without routing power through the beam you could use a much lighter beam and have a nice solid axle at the same time.
BuffMyRadius, Oct 06 2011
  

       // Using the area under the bed is utilization of wasted space. //   

       Sure, provided you can somehow make an eight-cylinder engine that fits in a 7"x32"x40" space.*   

       *these dimensions based on a quick glance under my dad's Sierra 2500. Not verified with tape measure. My point is that the engine wouldn't fit there.
Alterother, Oct 06 2011
  

       // utilization of wasted space //   

       So where's the fuel tank ?
8th of 7, Oct 06 2011
  

       In the front, where the engine should be. The spare tire is in the passenger footwell, the cup holder is set into the rear bumper, and the transfer case is on a shelf in a warehouse in Des Moines.
Alterother, Oct 06 2011
  

       ah okay, you're wimping out and going for an IRS then ?
FlyingToaster, Oct 06 2011
  

       This is an excellent idea - with an engine under the bed, there would be no room for monsters, and Junior could sleep easy.
TolpuddleSartre, Oct 06 2011
  

       This could feasibly be built like the AWD version of the Porsche 911 (RS-4? Does that sound right?), but it would be a show-off vehicle only--shit for load-hauling, towing, and off-roading, now matter how low you geared it.   

       And before someone jumps all over me about off-road Porsches in the Dakar rally and such, let me remind you that those are Porsches, not semi-functional pickup trucks built on a Porsche-type chassis.   

       Here is the gist of my argument: A banana works very well as a banana, but if you try to turn it into a clockwork trout all you get is confused anglers and angry orangutans. Ooook!
Alterother, Oct 06 2011
  

       [Alterother] Ah, I was basing my measurements on a Ford Ranger, which has a cavern in the bottom of it apparently. Without frame rails from the inside of the truck bed to the bottom of the body work is just shy of 12 inches.   

       I thought about a 911 style AWD system but that means rear engine and dead pickup drivers. Under my current plans there is no way to get power to the front wheels, unless someone knows a way to route a driveshaft through an engine?   

       [FT] I don't care what kind of suspension gets run in the rear, whatever you all agree is best -poof!- With the mighty power of halfbakery it has just happened. The rear suspension will in no way effect where the engine and transmission are.   

       The fuel tank is either behind the rear axle, or under the front trunk, I'm still fuzzy on how this thing is going to balance out. The spare tire is smack behind the radiator, the cup holder is in the center console, where it should be, and the transfer case is on a shelf in a warehouse in Des Moines because this truck ain't got one.
BuffMyRadius, Oct 06 2011
  

       // I was basing my measurements on a Ford Ranger //   

       Good idea; If you're going to make a truck absolutely useless, it makes sense to use one that's useless to begin with.   

       // unless someone knows a way to route a driveshaft through an engine? //   

       About a half-dozen spring to mind. I've always thought tubular crankshafts rather elegant, but maybe not the best for this application. I'm inclined to defer to The Toasted One for a more practical option.
Alterother, Oct 06 2011
  

       ... or you could replace an extended-cab's cab with a regular-cab's, leaving a gap between cab and bed. That would also look pretty nifty and you could keep the gas tank and spare tire where they are.   

       A stock Ford Ranger's underside is kept busy by the gas tank(s) on one side and the exhaust on the other. But both are going to be rerouted obviously.   

       //Ford Ranger...useless// more of a truck than the unibody ones. Still get better gas mileage than your deuce though not nearly as much as you'd imagine. *And* even the 'longbed'(7') only takes up one parking space.
FlyingToaster, Oct 06 2011
  

       I don't know what you mean, I can park my deuce in any size space. And mileage is something we don't talk about, though it's not as bad as you might think.   

       Even though both are pickup trucks, I find the comparison laughable. You could park a Ranger in the bed of my deuce (but only if you're paying me to haul it to the dump). Hell, the engine alone weighs almost as much as a Ranger.   

       Come to think about it, what we should really be discussing is a mid-engine deuce-anna-half.
Alterother, Oct 06 2011
  

       Ranger weighs almost 2 tons dry, less if I un-ducttape the mechanic from the bottom.   

       I don't actually see the point of making a deuce mid-engine except for looks... could use a couple JATO mounts amidships though, to let you get up the hills as well as down.   

       (mind I'm thinking the older bullnose, not the new-fangled multifuel model)
FlyingToaster, Oct 06 2011
  

       Mine's the 'new-fangled' M35. As for the point, well... There isn't one.
Alterother, Oct 06 2011
  

       If you're going to drop an engine into the back of a deuce it should be a tank engine... radial or turbine.
FlyingToaster, Oct 07 2011
  

       Turbine, of course. But if we're going that far, I'd much rather have the whole tank.
Alterother, Oct 07 2011
  

       Why have the engine in the truck at all? Throw it on the deck of the truck following.
Ah Supp, Oct 07 2011
  

       Most trucks need engines (or motors) actually incorporated into their structure in order to be self-mobile. There are rare exceptions, however.
Alterother, Oct 07 2011
  

       A turbine powered deuce and a half. Now THAT is an idea!   

       Did someone seriously suggest routing power to the front wheels through a tubular crankshaft? Show me where that has ever been done.
BuffMyRadius, Oct 18 2011
  

       I didn't say it had been done. I said that the technology exists (somewhere, aviation-related, I think), and I suggested, in not so many words, that it might be a solution to the dilemma.
Alterother, Oct 20 2011
  

       such a crankshaft would have no place in a conventional piston/cylinder engine. It also makes the use of any transmission currently in existence impossible. I think that a more conventional transfercase -> driveshaft -> offset axle would suffice.
WcW, Oct 21 2011
  

       [Ah Supp] If you want to have the engine towed behind the truck, you would then need to have some means of transferring power from the engine to the truck's wheels.   

       Convert the truck to run on electric power, then hook it to a genset trailer.
goldbb, Oct 28 2011
  

       //goldbb// UH, I dunno. Feasible but a bit Woosie. To me the whole purpose of trucks is to make them big, brash and macho with grunt in a size that takes up no less than half the road. Who would want to be seen driving an International Truck with a piddly little powder puff power unit?
Ah Supp, Nov 06 2011
  

       One of the premiere badass trucks in the world is the Unimog--most models powered by a humble four-banger.
Alterother, Nov 06 2011
  

       Who says that the genset would need to be "Powder Puff" sized? Sure, it *could* be small -- particularly if there were a nice big battery pack on the main vehicle (under the pickup truck's bed, where the OP suggests putting the engine), but it would be pretty cool to have a monster engine on a trailer -- and a bonus if one can put up signs saying "danger, high voltage" near the genset/vehicle connection.   

       As an added bonus, it would be trivial to swap between different power plants as needed. Bigger load? Disconnect the little engine and attach the monster. Going a few hundred miles unloaded? Switch to the lawnmower sized engine. Blew a head gasket? Leave the engine in the shop, and drive around on batteries for the day.
goldbb, Nov 06 2011
  

       For what it's worth, my Ford courier has a (measured) 510 mm, or 1'8", of usable height under the tray, without affecting tray height or ground clearance. The fuel tank occupies less than half of that space. I used to gaze longingly at that unused space, and considered at least mounting some sort of storage locker there.   

       (Aside: to me, "pickup" means transducer or microphone rather than truck, so I keep expecting this to be some sort of engine diagnostic or noise-enhancement thing.)
spidermother, Nov 06 2011
  

       [spidermother] That's a curious little tidbit you had there. Is it a modern courier?   

       In further news a senior engineering student at my college heard my idea and is so convinced it will work he is considering doing it as his senior design assignment. He even has the requisite Subaru SVX and S10 with a blown engine on hand. *cue outrage from both subaru and chevy fans*
BuffMyRadius, Nov 10 2011
  

       1978, flatbed.
spidermother, Nov 10 2011
  

       // both subaru and chevy fans //   

       I like Subarus and Chevys, and I'm not outraged. Aside from having to remove 111 bolts, screws and assorted fasteners to replace a light bulb*, I've never taken issue with a Subaru.   

       *I'm not kidding. Replacing the taillight on my friend's Baja required dismantling the entire tailgate.
Alterother, Nov 11 2011
  

       replaced a tail-light on my Ranger in less than 3 minutes a few months ago... 3 screws: the only issue I (theoretically) have is that they were screws not bolts: if I have to change the same light another 10-12 times they might strip out whatever's holding them in.
FlyingToaster, Nov 11 2011
  

       That's my point; in modern GM vehicles (which are superior to Fords in every respect), one rarely has to remove and fasteners at all for minor replacements. Subaru: good cars, but far too complicated for something not devised here at HB.
Alterother, Nov 11 2011
  

       I think the windows on the Soob sports car back a couple decades was designed here.   

       Meanwhile the only thing I will concede GM is that there's a possibility their climate controls are laid out in a non-absurd fashion.
FlyingToaster, Nov 11 2011
  

       I'm afraid that I may be biased by the fact that _every_ Ford vehicle I've ever driven had something wrong with it. In addition to about a dozen rentals and company vehicles, these include the '97 Explorer I owned until the front left suspension assembly fell off at 45mph in 2002, and the brand-new Taurus my mother bought in the early '90s, which suffered a front brake failure literally as she was pulling out of the dealership.
Alterother, Nov 11 2011
  

       Ouch, my gobuggy is pretty well the same thing as a '97 Explorer under the bodywork... suspension seems solid so far.   

       Every GM I've known has turned to rust, ditto the Hondas and even the Audi. The current Ford is 15 years old and not a spot on the panels.
FlyingToaster, Nov 11 2011
  

       Okay, I'll give you that. GM likes to use layered panels in the body clips, which collect water and rust from the inside.
Alterother, Nov 12 2011
  

       Electric motor straight to the diff. Gobs of torque and easy to package.   

       30HP generator will produce all the juice it needs for the freeway, that will fit underneath easily. Because them truck guys won't buy it if it doesn't run on gas.
AutoMcDonough, Nov 14 2011
  

       That is a great idea, but one with the usual drawbacks; gear-shift issues, heavy batteries, spike in the old electric bill, etc...   

       Being but one of the HB's resident 'truck guys', I'd buy it without the genny in a heartbeat if you could promise me range. I've used electric forklifts and carrydecks quite often and thought, "if only I could get this kind of power to go more than 20 miles before the juice ran out." I'm all for vehicles that don't run on gas, if they have the same capabilities as the ones that do.
Alterother, Nov 14 2011
  

       //them truck guys won't buy it if it don't run on gas//I believe I detect a bit of tongue-in-cheek there. I read automotive articles and mfr releases and I swear they feed off each other without bothering to actually consult potential vehicle buyers.   

       //gear-shift issues// eh ?   

       //spike in the old electric bill// Price of Aluminium's gonna go through the roof in a few years.
FlyingToaster, Nov 14 2011
  

       // eh? //   

       I know EVs like Teslas have very smooth transmissions and wide gear ranges, but I have yet to meet a beefy torque- monster electric vehicle (e.g. forklift, carrydeck) that will shift on the fly. Perhaps such things exist without my knowledge; it wouldn't be the first time.   

       // I detect a bit of tongue-in-cheek there //   

       So did I, but I decided to take it semi-seriously to make my point.   

       // I swear they feed off each other without bothering to actually consult potential vehicle buyers. //   

       You don't say.   

       // Price of Aluminium // eh?
Alterother, Nov 14 2011
  

       CVT's help for tin cans... I imagine a geared transmission, standard or auto, would also work for EV's.   

       //Eh?// When the shift to electrics for short-distance commuting starts to snowball. Aluminum is what power lines are made of (even though copper's better).
FlyingToaster, Nov 14 2011
  

       Ah. I didn't see the direct correlation to the pump vs. plug cost quandary, other than both would continue to skyrocket.   

       //       I imagine a geared transmission, standard or auto, would also work for EV's.   //   

       Only if you make the motor match speed while the clutch is engaged, yes? Otherwise the resistance caused during shifting would wear things out pretty quick.
Alterother, Nov 14 2011
  

       Ya lost me. I haven't had to double-clutch a transmission in <coughmumble> years: syncros.
FlyingToaster, Nov 15 2011
  

       Maybe I'm barking up the wrong tree. As I've said before, my automotive knowledge is primarily based on practical experience, not formal education, and this leaves large gaps.
Alterother, Nov 15 2011
  

       But why wouldn't a clutch work on an electric motor ? The only difference I can see is EM's don't idle.
FlyingToaster, Nov 15 2011
  

       That's what I was talking about; the motor would have to match speed with the drivetrain in order to engage smoothly. But the more I think about it, the more I realize that's very simple to arrange and would not pose the problem I had first envisioned, even with a gigantic high- torque motor. I was being obtuse.   

       Battery weight is still an issue, however, unless we're operating under my usual assumptions of an unlimited budget and full access to cutting-edge tech.
Alterother, Nov 15 2011
  

       here is an idea. use the subaru boxer diesel engine but have an output shaft at the front and rear of the engine. at the rear axle use the trans axle out of a mid engine car and on the front axle use the trans axle out of a rear engine car both geared the same and set to shift in unison.   

       you would have to have the engine come up slightly under the seats in the cab kinda like a big rig but the end result would be cool.   

       think i want to try this now.
TAGAutoSports, Mar 28 2012
  

       //have the engine come up slightly under the seats in the cab//
google "COE pictures" for some seriously cool looking pickups.
FlyingToaster, Mar 28 2012
  

       //google "COE pictures"//
just shows images of a former Olympic champion middle-distance runner, and Tory peer.
AbsintheWithoutLeave, Mar 30 2012
  

       hmmph, you must be personalized or something... try "coe pickup"
FlyingToaster, Mar 30 2012
  

       //try "coe pickup"//
Now I'm getting a dating site for former Olympic champion middle-distance runners and Tory peers.
Oddly, the only member appears to be William Haig.
AbsintheWithoutLeave, Apr 02 2012
  
      
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