Kinda makes me want to find an old wood runabout with an inboard engine and convert the whole works into a cyclecar "skiff". -Dave
The first competitions on go-cart racing in Soviet Union http://www.youtube.com/watch?feature=player_embedded&v=n_1oOMC3gA8
This may be of interest on this thread It's my take on a cheap to run hotrod/cycle car. There's a bit of Sandford, a bit of BSA and a bit of hot rod in it. Still in the very early stages - trying to size everything so I can keep it low and still fit. Luckily I'm a short house! Would have a tube/box section frame and an aluminium skin, riveted on with some nice dome heads to keep that aircraft feel. Power is from a Geo Metro engine through a Beetle gearbox for front wheel drive. The gearbox has the ring and pinion flipped and it has been turned upside down, to ensure a lower hood/centre of gravity and keep four forward and one reverse gear. Space in the back has been left for a great big LPG tank for fuel. Weight has to be under 450kg/990lbs. Seen some 1300lb rods here with 289s and a rear axle so should be doable - my power plant is only 70lbs ish. Would be better to think of this car as an alternative to the econobox (want to do 100 miles a day as cheap as possible and still have the space for me and she who must be obeyed to take it on holiday - fitted luggage trunks to fit in the boat tail should do this) instead of a hot rod. If I get bored of 50hp they can be turbo'd to 100+ which isn't bad on a car that weighs less than half a ton. Anyhow, back to some proper machines!
Cool. The only cosmetic changes I'd make is to droop the top of the tail downward and / or move the rear axle forward a tad if you can still sit in it! I saved your plan for general reference... thanx. Gary
Still not sure on what I'll do with the shape of the boat tail. I originally thought of drooping it more like a Morgan Beetle back, but I quite like the nose down hot rod rake that leaving it higher gives. The late Jalopy Joe made a boattail A that looked quite well proportioned, but a bit too low for me. I'm afraid I had to move the axle back so the wheel clears the LPG tank (big rectangle on the floor).Wheelbase is 111 inches at the moment, I did have it at 107 but this is a compromise for the tank. I reckon when it's sitting on the ground it'll be damn difficult to see the rear wheel anyway. Ground clearance is at just over 4" under the frame at the moment, and a little less under the lowest part of the car (vw Bellhousing). I might be able to raise it another inch for practical reasons without it starting to get top heavy and look a little goofy. For those interested, that circle on the side of the cowl represents a sort of worst case scenario centre of gravity. If it's any higher or any further rearward, the car would tip instead of slide on a hard corner (assuming an optimistic cornering force of 1G). I reckon I can keep it lower than that thought. Next stages are designing the structure. Kind of have to put a fair bit of thought into it to keep what I want - weight under 450kg and a bit of impact and roll safety (I can't justify not putting roll bars on this car. Twin hoops don't look too out of place and lets be fair, I'm in the UK, how often will the roof be off?!).
Because it's front-drive I'd raise or curve the line at the bottom of the tail to expose more of the rear wheel. I'd simultaneously curve the top of the tail down, so the whole has a sort of finch's beak profile. The rear wheel ought to be a delicate little thing, not quite a motorbike wheel but not much more. I explain my reasoning around this in Gary's bigs 'n' littles thread.
Hi Dawie. For practical purposes the rear wheel is the same size as the front two, so they're all interchangeable with the spare (hoping I can make a single sided swingarm and have all wheels bolt up the same). Again with the boat tail I'm not sure what I want yet. Aerodynamics are definately going to have a role, but so does aesthetics and practicality (luggage space - note the spare wheel currently sits in the boat tail, with not a lot of room to spare. Same deal with the lpg tank). Playing around with the aerodynamics side will come much later - I haven't ruled out a roof tapering all the way back to the tail, depending on how advantageous it is. Have just read your part in the big n littles thread and agree about the weight at the front. I reckon the highly tapered boat tail (dotted line) when viewed from anything other than side on looks quite light and spindly, even with its current proportions. The front by comparison, with the tall tyres, exposed exhaust, louvred hood, possibly cowl steering and that superchargerish vw box stuck out the front make it look front heavy, even though it's 'lower'. Think greyhound stretching. I'm afraid for me the aesthetics of having a wheel at the back anything less in size/mass/bulk than those at the front just don't add up. The same size works for me, afterall, there'll be equal weight on all of them (best laid plans etc). In an ideal world, this would be rear wheel drive, but for a commuter car FWD just works better for a reverse trike. Too much snow/mud/sh*t in the middle of the roads I'll be driving on, and all the complexity of shafts and bevel boxes and belt drives or shaft swingarms is avoided. Anyway, I don't want to hijack this thread, I just thought these sketches might be some food for thought.
I don't think it's a hijack -- it's pretty much a cycle car, or at least in the spirit of one. Would be licensed as a motorcycle in most states due to three wheels in the U.S. I know the UK at least used to cut the three wheelers some slack, which is why the Reliants and such were popular a lot longer than in any other developed nation! I suppose you're going to adapt the Geo front suspension to the VW transaxle? Assuming you have a complete Geo to donate the engine you may as well, though you probably don't want struts in front. you could make them work and look good though. Make it look like a Morgan front suspension with struts instead of the sliding spindles, and mount the headlights on the cross brace near the top.
I think independent front suspension is necessary. I'll more than likely use the front uprights from a different Metro - this time a Rover. The Rover Metro (and mini) used twin A-arm suspension and FWD, so the uprights are ideal. The rear suspension uses trailing arms, which I could adapt for my rear suspension. They are also common as anything, I am much more likely to find a donor closer and parts are easier to source, and because of the similarity to the Mini there are all kinds of upgrades and other nice bits that fit. (Geo Metros, or Suzuki Swifts as they are known over here, are available but quite rare. The engine can be had from a breakers yard, there's usually three or so on ebay UK at any one time). I'm thinking about doing somthing similar to BSA suspension - kind of like wishbone suspension but with a transverse leaf forming one of the suspension arms (because of the gearbox it'd probably be the upper side). It could be tuned like Corvette rear suspension to offer some form of anti-roll without sway bars. I think the idea is simple to build but quite difficult to design so that it works well, and if it doesn't work, mounting the spring rigidly is easy enough. That avoids the trouble of having frankly ugly coil springs hanging out in the wind. I'm also quite keen to avoid it looking like a Morgan. I think Morgan three wheelers are stunning - but there are plenty of knockoffs and replicas around and I'd like this to avoid any pretentions of being another.
With no engine out front I don't think you'll have a problem not looking like a Morgan no matter what else you do. The leaf spring as upper arm might work, you'll just have to make a shackle like bracket for the upper ball joint... which is the problem with that idea. The ball joint bracket needs to be held so that it doesn't flop around, and a single attaching bolt to the end of the leaf won't work. It worked for some old cars because they DIDN'T use ball joints, but had a vertical pin in a bushing. On a Corvette rear axle the leaf isn't the arm, it has links similar to sway bar links attaching it to the arms. A shackle or Corvette type link attached to one of the A-arms might be your best bet. With such a light front end I seriously doubt you'd need a sway bar.
What one would need to get the transverse-leaf idea to work is to terminate the bottom leaf on each side in a flat, square end with a few bolt-holes in it. To this is bolted a simple mild steel plate with corresponding bolt holes and provision for a steering ball joint. The latter usually requires either a single big round hole or a big round hole with a few smaller holes around it. I don't know Rover Metro suspension detailing but if I remember correctly Minis had cast control arms: were the ball sockets cast in? Either way it should be possible to adapt bolt-on ball joints to BMC etc. uprights. The antiroll aspect of the Corvette transverse leaf was also found at the back of the Fiat 128 and its derivatives. It might even have originated at the front of the rear-engined Fiat 500, 600, and 850. It basically comes down to holding the leaf to the car's structure in two places rather than one, and allowing it to rock in its mountings a bit. Then the leaf arches simply in bump/bounce/pitch/squat but bends into an S in roll. The spring offers far greater resistance to flexing in an S than in a simple arch. The greater the distance between the mountings to the vehicle structure, the greater the effect. Note that space is needed for the middle of the spring to move up and down as it flexes.
The Mini/Metro ball joints (either upper or lower, but I believe either could be swapped top or bottom on the upright side) are designed to be bolted rigidly to the cast A arm. They have three bolt holes in a flat plate that would work perfectly in the leaf configuration. Other advantages of the Metro uprights are that the steering links are not cast in, they are bolted on, so custom links would be easy. Didn't know that about the Fiats used a similar system, very interesting. As far as the roomfor the motion that's somthing I'll have to model some fashion - a lot is going on in the front of that car. I presume for this kind of suspension, there are fewer 'small' leaves in the spring pack - enough flex must be had in the centre to allow the S curve and associated anti-roll? Without, it's just a leaf spring that effectively mounts to one single very wide mount, with all flex outboard of it.
Well, there you go! Just drill the right bolt pattern in the ends of the main leaf. I once had a complete Mini front subframe with suspension sitting in my lounge for me to stare at, until I figured out that there was no way to turn it into an irs for my Minor with any degree of elegance. I did a lot of staring for over a year but now I can't remember half of the detail.
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