Weight reduction: Running out of ideas.

[73c34me]

26 lbs. is what comes to mind when I removed & weighed the heater core, fan cage & box, hoses, coolant amount, duct work, blower motor etc. on my 73.

 

[rtj]

Here's another for guys with convertibles. I just picked up another hardtop and I swear it is half the weight of the red one I have on my old car. I'll weight it and update this. I've heard that mentioned on other forums, so maybe one is earlier or aftermarket.

The recent one has spiderweb cracking so the plan is to do/try carbon fiber skinning with low temp epoxy. I got it really cheap.

 

[Corvettes White]

Okay My attempt to go light. An aluminum AC bracket for my '69. Had the iron piece cast and polished. George

 

[1Michel]

Okay My attempt to go light. An aluminum AC bracket for my '69. Had the iron piece cast and polished. George

did you cast this part yourself?

 

[Corvettes White]

Small foundry in So Cal. Use to be a lot of them to support aerospace. 70 for the two pieces. Free cast.

 

[69427]

Okay My attempt to go light. An aluminum AC bracket for my '69. Had the iron piece cast and polished. George

Cool!
I've been tempted to cast a few items like that also, but just haven't had the time to set up a micro-foundry kind of thing. My dad used to cast aluminum parts for his race car back in his youth. It looks like an interesting thing to try.

 

[69427]

Making a little more progress.

Got the outer housing initially shaped, with a bit more tweaking to do yet. It's 1/16" for strength, but that also makes it a bit tougher to bend and shape. I've got three chambers in it. The first chamber is primarily a surge volume/attenuation piece, while the other two are primarily attenuation pieces, similar to a pair of glasspacks in parallel. Below is a test fit.



I've drilled a couple hundred holes in the tubes, along with a few dozen slots to allow noise/vibrations to interact with the fiberglass and SS packing material around the tubes. Still have a similar number of holes and slots to cut yet before I can start to weld the end caps on. I also need to polish the exit pipe so it looks similar to the stainless tip on the other side of the car.

Right now the weight is 7 1/2 pounds. My target is 10 pounds (six less than the muffler it's replacing).
I was looking on ebay and found some inexpensive sound dB meters. I'm going to order one, and then hopefully be able to make a reasonable judgment on the comparative noise reduction capabilities of this and the other side muffler.

 

[redvetracr]

did you see the guy on ebay selling fiberglass replica bumpers & bumperettes?

 

[69427]

did you see the guy on ebay selling fiberglass replica bumpers & bumperettes?

No I hadn't. I did talk to a guy last summer who had them/similar pieces on his '69. There's probably 15-20 pounds that could come off the car with those pieces, but I'm still a bit shy about making these C3 antiques any less safe than they already marginally are.

 

[Kid Vette]

I've always considered the bumpers as more of a part of the trim than a safety item. :wink:

 

[84rzv500r]

I ripped out all of my heater assembly, controls and everything, a long time ago with no regrets.

I consider my Vette a 4 wheeled motorcycle; if you don't need it on a motorcycle, I don't need it on my Vette. :thumbs:

never thought about it exactly that way but our philosophy is the same :lol:

if it don't make it faster or safer then I dont need it:beer::beer:

 

[69427]

Finally got the muffler welded up. I still need to smooth the edges and polish the outlet to look like the SS tip on the other side, and then put a coat of flat black paint on it to match the other side. The weight ended up at 10.1 pounds, while the previous (now spare) muffler was 16 pounds.



I ran the engine for a while and stuck my head near the exhaust tips to see if I could discern any differences in volume and tone between the two sides. The volume level seemed pretty close (I've got a sound dB meter ordered), but the tone was slightly different. The RH turbo muffler had a nice calm low tone to it, while the new muffler had a slightly higher tone, with a kind of burbling sound that reminded me of the exhaust sound on my buddy's Olds 442. It's a nice exhaust note, and I can live with that.

 

[69427]

2780#

I disassembled a good chunk of the rear suspension and exhaust yesterday to swap out the C3 batwing for a weight savings C4 batwing, but first I decided to get a quick weight on the car before it's out of commision again. I took it to a local truck stop by the interstate the other day and put it on the scales. With about an eighth of a tank of fuel and no spare tire/tub, I got a reading of 2780 pounds (I'm assuming it's +/- 10 pounds rounding error due to the weight range and display resolution).

If everything goes as hoped, the modified C4 batwing will be 5# lighter than the C3 batwing, but I also ought to be able to pull an additional 6# off the car due to the removal of some steel brackets I welded up to adapt the C4 leaf spring and C6 toe rods to the C3 batwing.

I've also got an aluminum front suspension crossmember partially constructed, but I first need to pull the present steel front crossmember out and build a jig around it so I can get all the spacings and geometry points (LCA mounts) of the new crossmember in the correct locations. I'm hoping for about half a dozen pounds off the front end with that piece.

 

[Danny Boy]

How much does the driver weigh?

 

[rtj]

http://www.astrotops.com/68_82tops.html

17 lb one piece top I saw the other day. Carbon fiber would be better if someone made them.

 

[phantomjock]

17 lb one piece top I saw the other day. Carbon fiber would be better if someone made them.

Once upon a time - Ecklers and others had a collapsible Targa Top -- Called it a Rain-cover, something like that. Could be pretty easy to DIY. Save a heap of weight. Could glue Velcro tapes to leading edge to keep it down.

Cheers - Jim

 

[69427]

How much does the driver weigh?

See post #298.

 

[Danny Boy]

How much does the driver weigh?

See post #298.

I saw that post.
All this effort to reduce the weight of the car as measured in ounces at the cost of possibly weakening the structure. The human body can lose pounds and be actually stronger and safer. Just sayin'.

 

[69427]

How much does the driver weigh?

See post #298.

I saw that post.
All this effort to reduce the weight of the car as measured in ounces at the cost of possibly weakening the structure. The human body can lose pounds and be actually stronger and safer. Just sayin'.

Two things:

1) I'm a design engineer. I have a decent working relationship with the laws of physics, materials strength and properties, and several unpleasant-to-learn varieties of mathematics. I'm not just sitting under a shade tree drinking a beer and butchering up a car.

2) I'm 6'3" and 200 pounds. Is it your position I'm portly?

 

[Corvettes White]

As an aside it still takes a bit of nerve without the resources of GM. A saw a photo of a fatigue testing machine cycling C3 trailing arms. Now if I were to make some trailing arms, I would have a hard time reassuring myself I got them right. Same goes for a lot of other parts. Kudos. George

 

[rtj]

Bringing this one back to the top, good thread 69427.

I’ve got 3 different convertible tops, varying from light to heavy. I’ll grab some pics and weigh each one in the next few days.

 

[vette427sbc]

Im really interested to see what StingrayComposites comes up with for either a carbon t-top of 1 piece targa... The factory tops are pretty heavy and are the "highest" weight on the car.

On another note, I chose to do the fuel lines in my car with aluminum tubing over steel or stainless... a roll roll of the alu tubing is notably lighter than the stainless roll of the same length. Thats a PITA job for marginal weight that is already down low though

 

[Bullshark]

Not a fan of aluminum tube fuel lines. The marginal weight reduction doesn't make up for the compromised safety, IMHO.

Which brings to mind this recent scary event. A friend, who has just finished his experimental airplane build, suddenly lost power at about 3k ft altitude. After going through proper protocol, he looked down and saw an old airfield with big yellow X's on the runway below him. He immediately dead sticked the plane down, successfully landing with no damage. He left a trail of fuel the length of his landing. Turns out he had a broken aluminum AN coupler in the fuel line. Looking at it, it appeared to this EE to be a fatigued aluminum tube within a swivel female to female coupling.

I told him not to bother buying a lottery ticket in the future, because his luck is all used up.

 

[mrvette]

I don't recall ever changing the fuel line in my '72 vert....but did have the rear brake line fail, right under the driver seat, so got two lengths of brake line, spliced them together with a brass fitting, I forget if compression or flare, probably flare.....no biggie....but an ALUMINUM fitting?? don't think I ever seen one, let alone USE one.....

:surrender:

 

[OZgreen69]

Well? If you look at modern fuel injected cars, you will rarely find some steel in them, they even are in "plastic" ! And alloy is certainly easier to bend than S/S !

 

[rtj]

Three different hardtops

Red, looks like a factory top, with 69 date written in grease pencil. Trim and weatherstrip intact. No interior, no latches.

51.2 lbs



Blue, says "Parrish Plastics" on rear window. Indoor/outdoor carpet glued in for interior. No latches, bolts on with 4 bolts (not included). Shell construction.

34.2lbs




Attachment:



Bare fiberglass

No rear window, no trim, no weatherstrip, no brackets. Similar construction as factory.

Weight 33




Factory brackets no bolts 1.78 lbs



My brackets 0.61lbs

 

[OZgreen69]

Going on my car from a 1" front bar to 1.1/4 gained 6.60lbs more !!

Have you checked the weight of the alloy hub on the original steering wheel ?
1.54 lbs!!

I did replace the hardtop glass window ( 9.26lbs ) with Lexan , and not refitting the roof lining ( 13.99lbs ) as well.

Another funny one is the original radio + speakers = 8.81lbs

Electric window mechanism + motor per side = 8.70lbs . I should have check the elec motor alone, as I am still using the manual mechanism.

Removing the protective tar from underneath the body an wheel arches = 3lbs!
But the weight of the roll cage = 21.27 lbs

A China made radiator frame =12.5lbs Original =13.9lbs See!! China stuff is really good !

Brake master cylinder Iron= 8.59lbs Alloy = 3.74lbs

Another that you don't see too often on Vette anymore, is the hub cap of the rally steel wheel = 1.76lbs + wheel trim at 1.32lbs = 12.32lbs for 4 wheels !

 

[rtj]

Going on my car from a 1" front bar to 1.1/4 gained 6.60lbs more !!

Definitely trade-offs.

A carbon fiber convertible top and deck lid could save some serious weight. Like this unit:

 

[rtj]

Window delete could be an option, but it probably increases drag.






I’ve got two deck lids, 1 stripped and 1 complete. I’ll weigh them later.

 

[rtj]

Convertible deck lid

With all hardware: 28 #

Stripped: 22#

So a one piece top and deck lid could save a bunch.