Ultralight cars...how low can you go?...

Hey everybody, long time lurker, first time poster here.


Let's see how far we can go with this theme...consider it a thought experiment.

I'm wondering, how low weight a car could be built within the theme of the HAMB (i.e. no carbon fiber type stuff) that can be still made road legal and reasonably driveable.

1000 lbs? 750lbs? Less??

So what can you come up with as far as frame/body/driveline etc that could be cobbled together into a running, driving car?

 

I am pretty sure 1200 to 1500 is attainable with a banger powered modified. I have targeted 2400 for my truck. If I can make the power I want at Miata weight, it should be very interesting...

 

A friend of mine has a couple Berkleys made in the late 50's or early 60's that look like 1/2 size MG midgets. They were built with 350cc motorcycle engines, aluminum and figerglass construction. He is road legal in wisconsin with a motorcycle plate because they weigh under 750 pounds.

 

I believe Pete Chapouris built a Model A roadster for his dad that weighed less than 1500lb, and it was a LOT of work. Reason he picked that as a target was because you could LEGALLY run without fenders (I think that's a California rule).

I do believe it was V6 powered, which kind of made it ever so slightly less cool, but it was a great looking car. Dark green, steelies etc... very HAMB-friendly.

And that was 15-20 years ago!

EDIT:

The Internet is an amazing thing. Two seconds on Google and look what I found.

It was actually a T roadster.

http://www.streetrodderweb.com/features/0403sr_ford_track_t_hotrod/photo_02.html

Can't tell me this ain't HAMB-friendly.



It's a Ford Capri V6, so I guess that's kinda OK.

 

I have been toying with the idea of a track roadster with a Lotus 7 inspired chassis with a 4 popper for power. The original 7's hung out around 900-1100 LB. I'm probably at least somewhat optimistic as the engine would constitute a significant amount of the weight. Even a Model A plant would be too heavy to make the weight. A 215 Buick (3.5 Rover) could work. I have a Quad 4 I was thinking of dressing up as much like a Miller / Offy as I could manage. With a beam up front and a live axle out back (I have been looking at the Toyota '10 bolt' as I have a few).

Would be a scream, as anything with more power than a Briggs and Stratton would make it scream. For that matter a motorcycle engine would work, make it a 'cycle car' (wasn't there a thread about those here somewhere?) if you are going for the ultimate in lightweight.

Of course you could build a Monocoque tub for it, out of marine ply maybe? But I imagine you would play hell getting your DMV to buy off on that.

 

When I was at So-Cal, I took one look at Petes fathers Roadster, and instantly disliked it personally, it did not have that hotrod sound or look I liked, which is all opinion anyways.its well built.......This little Roadster has been driven everywhere and showed that it was well used........I later had a chance to ride in this car, and after being in California a couple of months already...finally realized the value of this car, Pete had built it awhile ago but it was totally relevant to todays time....with gas prices and crowded roads...you can just aim that Roadster anywhere and it will take you with no problem........and I knew better, you never judge a book by its cover......I wish that Roadster was mine and hope to have some of the vision Pete possesses one day........Littleman

 

Lol...yeah, that one might be a bit difficult!


Brootal, regarding the Pete Chapouris car, this is actually quite similar to what a friend of mine suggested when I brought up this idea. He figured you could put together a 2"od tube frame and drop a "race weight" (the ones with non-op doors and no floor) fiberglass A or T body on it. Power would be a quad 4/T5 and full hood to cover it all up.
I thought it might work, but it really would depend on a well engineered tube chassis, and exactly how heavy one of those motors is.

 

i'm shooting for 1500 pounds on my track t..... 20r toyota with a little comp 280 magnum cam ....5 speed and 2wd toyota rearend...go kart with a clutch.... brandon

 

Man -- those are clean lines, IMHO. I think it looks great.

I'd probably lose the hubcaps, and go bare steelies for a little better look, but I think it's cool.

I think a body like this, a small MG plant, like a midget motor, a single SU carb, a header out the side - or a bike motor, if you can make it look cool enough.....

That'd be a fun ride.

Pete

 

my Model T, weighs 1680# with a full tank of gas. 292 chev 6 and powerglide.

 

I have a134'' fed built out of c/m tubing a sbc, glide and olds r/e. I could drop 50 lbs with alum heads another 25/35 lbs with a diff r/e. that would put me at 1065 add a alt ,rad,and all would take you back to1220. my frame weighs 85 lbs. just thought I would post some weights.

 

My a/fx falcon started as a 2 door post 6 cyl. 2300 lbs new, I have removed/ drilled a little over 500 lbs out of it, I am hoping for a finished weight of around 2400 lbs with 400+ horse power.

 

A nicely built buick v8 would work very well for one of these lightweight builds.

if you went with an aluminum body minimal frame you could probably just break into the 1500lb barrier with a v8. current sprints are very light. you were looking at 1400lbs back about ten years ago before they got real exotic.

 

So where do you draw the line between light weight rod and this...?



http://www.stevproj.com/Carz/CycleKart.html

http://www.jalopyjournal.com/forum/showthread.php?t=231272

 

engine choice I would say. regular car engine=rod

 

That is what I was thinkin'.

In the cyclecar thread I suggested using a suzuki samurai engine and trans. all aluminum, very compact, and some aftermarket hop-ups available. Using other small car components, a cool single seater could be super light and scary fast.

 

A stock 1921-22 Ford T roadster is already in that weight range with the heavy stock engine/trans (well upwards of 500 pounds), heavy wheels, and full fendered. They weigh 1380 lbs w/o starter and 1475 lbs w/starter. Seems to me that 1200 lbs would be very easy to obtain for a banger powered modified, and that 1000 lbs. could be fairly easily reached. Think about how heavy just the stock T roadster top and bows are. Just removing the top alone would knock off maybe 100 lbs. and maybe more. (I've never weighed them, but I've lifted them, and they are heavy!)

 

I read about those too, and they are extremely cool. However, like I wrote in the original post, I draw the line at whatever you could make street legal and reasonable to use on the highway....of course...if you could register one of those cycle carts...that would likely be the lightest possible option.

 

I have been tossing this idea around for a while...

The cycle carts typically use wooden frame rails. Would that be any lighter in a model A size package? Now suppose I only need 1 forward gear and 1 reverse with no clutch. Empty T5 with just a main shaft, maybe 30 lbs. ? Fabric body along the lines of a biplane? Cycle spokes with brakes only on the rear? Can 103" wheel base stay under 800?

 

Just because the ones pictured are wooden, doesn't mean what you built would have to be wooden. People were posting the "little cars" to open your imagination.

A cylce car sized car, built out of metal, using real suspension would be cool as shit. Instead of calling it a "modified", call it a "really modified".

 

True, but how do we make a regular sized rod very light without exotic materials or chassis designs?

I'd like 2 seats and decent performance to 70 or 80 mph. Open cockpit is a given. Tall, skinny tires, a minimum drive train, adequate brakes.

I really want to go electric, but the weight saved is off-set by the batteries required. Maybe an air-cooled twin?

 

Morgans were built with ash wood chassis up until 10 years ago. You may still be able to buy them that way. Those are fairly lightweight cars too. MG sized.

 

or even a aluminum frame drilled out every so often would be light... not as light as wood... but twice as durible...

 

I think if using a basically traditional layout, the big sticking point is the axles. What's out there that's really light, especially the rear?? There are insanely light engines around suitable for a flyweight car, from Crosley to modern motorcycles...body and frame can be made very light by someone capable of the fabrication, either in tubing or riveted aluminum monocoque...
Didn't Issagonis actually design a car shon in an old HRM with plywood monococque hull?
And look at the Miller pedal car in that discussion...my first thought was "Hey, that lloks big enough to swallow a Crosley engine and a couple pieces of tubing..."

 

Another wierdo datum point...anyone remember "Roger builds a roadster" in HRM in the '60's?? Roger Huntington laid out a radical ultralight T-bucket, bolted aluminum channel frame, much selecting of parts for weight...everything flyweight except the odd choice of a Pontiac V8. That car was shown half-built...and I've never heard of it since!

 

I think that a T based Modified using a stock width roadster body with an A or B engine completely fits your requirements. Why reinvent the wheel?

 

I've been planning a light weight build as well - looking into the 3 cyl from a Geo Metro/Chevy Sprint, Suzuki Samurai transmission (apparently they bolt up to give you rear drive capability). Was also thinking along the lines of all aluminum construction - Superbell Alumibeam, aluminum frame rails, etc. I found some aluminum 18" spare wheels from a Mercedes SUV - they look kinda like steelies and are really light. I also have a 3/4 midget q/c I thought might work - I need to see if I can have it built to handle what I'm thinking of doing. Threw around the idea of running GM G-Body ('78-'87 Malibu, Regal, GN, Grand Prix, Lemans) aluminum rear drums and brakes at all 4 corners - small, cheap, light and they look quite a bit like the old 12" Buick finned drums. Have an old glass '27 roadster race weight body (no floor, doors, etc.) that's in the way and may get cut up to use. I think this one could come in at around 1200 lbs, maybe less. It would only have about 60 hp but should be very economical.

Steve

 

The trick is to make it handle like one too!

My goal is a T-Road under 1300lb, with a traditional V8.
Can it be done?
Somebody do it and let me know.

 

Aluminum Buick Special V-8?? Looks just like a real motor! Weighs nothing, and could drop some of that with modern electrics...

 

The samurai engine/trans combo is less than 200 lbs. There might be something else out there just as light and make more than 60 hp.

If you build somehing at least halfway aerodynamic, it should fly.