weight saving - second analysis wanted.

[4age]

For my winter project I won't be able to use much monetary resources. More power is out the door but saving weight is for the most part free. This is the rough first edition of what I would like to do. Cut and tube front end with very simple 2 tube design and use carbon rad support, fix mount the headlight buckets, cut the rear from behind the shock mounts and reinforce panhard mount. turn the doors into a skin with no windows, remove; the hood sub structure, dash bar and ignition mounts, any brackets, roof and sub supports. The roof may not seem like a significant weight saving tactic but it has a lot of body filler on the top that would justify the removal. I want to cover the rear with aluminum mesh covering coroplast secured over rubber seals. The front tubs I would like to use some abs plastic salvaged from various oem bumpers. roof would be aluminum riveted on over rubber.

Next would be stiffening up the chassis with a tube structure, tying in the tower mounts and frame rails also supporting the roof and door gaps, stiffer and centered weight. Cold rolled steel would probably render the entire exercise useless, aluminum i would have to get a spool gun but believe that would be a worth while investment. Chromoly would be ideal but too expensive and i do not have TIG. Lexan hatch and rear windows would also be really nice but also too expensive. I have aluminum 4 links, i feel i could squeeze a single piece drive shaft out of my bank if the weight is significant, also i heard some old hot rod legends saying that said person could shave the casting marks off the block and lighten the brackets. lithium battery would be great if found cheaply or a motorcycle battery. i don't run a passenger seat, I sit in a bride fixed back, nardi wheel and a harness so removed heavy seat belt assemblies. extend the control arms instead of spacers for wider front trac. aluminum under axle exhaust from headers. Next year if i can afford it i will switch to megasquirt and scratch build a light harness. if i made a order of resin i could single piece the front end and duplicate the hatch with polyester fiberglass but i haven't checked into the prices of that. i think those are all the ideas I have besides hitting the gym and eating less. Im open to opinions on the whole plan or more weight saving ideas and would actually appreciate it, whether pointing out flaws or proposing new ideas. It is not a streetcar nor have to meet any standards its my toy and learning object.

[Warren]

Thin wall steel cage is the only way to go. The second you drive your car aluminum will crack.

[Blade7]

I just took out most of the stuff from my hood, and the front is too weak, so now I need to brace it with aluminum. I took out my hood latch assembly and cut my rad support and used aero catch pins and a piece of angle aluminum. The guys in Japan take out all of the front rad support and replace it with one piece of aluminum angle, but usually on a levin. If you're not going to run head lights and just use empty buckets, then I would say try that, it also lets a lot more air into the engine bay.

I was pricing lexan myself. Scratch resistant stuff was $416 for me to do my rear windows and sunroof, and only $135 for the other stuff. I was looking at 1/8". If anyone here has used either, I would like to know which is more worth it. I think 1/16" could be used, or just run without windows at all?

[DiscoQuinn]

I like this thread a lot.

[projectae86]

Weight savings? Where we're going, you dont need weight savings!

[4age]

I had not looked into actual aluminum tube info yet, but good to know it cracks since it would be a lot of work to use anyways. Boat and car trailers use a lot of aluminum with pretty stiff suspension but that's my only analogy. 1 inch steel tubing wouldn't have the right look, 1.5 might, what wall thickness do you suggest? Also is it a possible idea to slot the unstressed parts of tubing like a Grim Reaper frame?

The lexan I looked at must have been the scratch resistant stuff, $100-200 would be manageable. The weight savings of glass would probably be the best way to cut weight, besides lithium battery. I have some carbon scrap I picked up and will use that where I can but there is a nice piece for the rad support.

Speaking of Back to the Future, I made this a couple weeks ago...ignore the "gate scott"

[bongmuon]

Make a shallower oil pan and run less oil. Instead of aluminum roof use a light fabric stretched over the cut out steel. Do the hood the same with some thin aluminum tube substructure to keep it off the engine.

Gather a bunch of free old bikes to source tubing from the frames. keep an eye out for lexan/acrylic for sale on kjiiji, I found an 8x4 ft sheet for $50 once.

[Sparkie]

how does miata/s13 IRS compare to corolla live axle in terms of total weight? could one get some aluminum control arms in there to help?

edit: also I've mentioned this idea before: Bumper muffler. save weight by making two parts into one.

double edit: polyethylene gas tank. find a HDPE tank that fits enough and live the rust free dream.

[JungleMatic]

Stock rad. Water weighs a lot.
Everyone buys an aluminum rad to save weight and then adds like 4 times the volume of water to the very front of the car.
Move it back as close to the engine as you can.
(move the whole engine/tranny back too)

If you've got a hard top don't bother with the roof skin. It's a ton of work for just a few pounds. imo.
Japan is always cutting roof skins off though, maybe it's heavier than I think. Seems mostly cosmetic though??

Calipers and brackets to aluminum. Lots of sprung weight there.

As mentioned before, a few times, doors. They are insane heavy.
Hatch as well, you can cut almost everything out of it.

Don't goo too crazy on the hood. It turns into paper and just ends up flopping everywhere. (I had to add some back for rigidity...)

[clay72]

Fill the tires with Helium.

Or, better yet, Hydrogen. Blow a tire drifting on those and put on a real show!

Also, drill holes in your block and cover them over with cellophane to hold oil in.

[projectae86]

How has no one mentioned speed holes???
Id post a picture but I guess its too hard for the one on my computer to be posted...

[4age]

Hydrogen and fabric panels sound really great! if it worked for the Hindenburg it can work for me as well! ...

I wouldn't think cutting the roof was worth it but mine has a half inch on bondo on it so that changes things a little. I have 15's on there now i could go to 13' and Skinner tires but budget restrictions will probably leave me with 14'' supra rims.

I found some pretty cool brakes in the midget racing world but probably +3k to setup...dreams

[Dirt-McGirt]

Or put said time you would spend Cutting your car up to make it even more of a noodle... on Getting a second job and increasing your budget for more use full things? like an extra 20hp.

Unless this is a full on track car... but if thats the case, you will still need a second job to support your Racing.

****ed both ways.

[Dirt-McGirt]

yes, i am being a bit of a smart ass. haha. But Giving serious advice at the same time. I have seen and been involved with alot of Race cars, from budget racers to big budget cars. I have seen some good ideas... not work so damn good and render a car more or less garbage. Choose wisely where you decide to "tube" and Cut **** out, especially on an old noodle like an 86.