Just dreaming: Aluminum C3 frame. Input?

69427

The Artist formerly known as Turbo84
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Clinging to my guns and religion in KCMO.
I'll admit I like the looks of my '69 better than a C6Z, but to be honest, I can't help lusting for an aluminum frame. I realize the C6 has the advantage of not being a ladder frame, and all the other tunnel and birdcage structural differences, but humor me a moment and throw me a few technical bits on why it's possible or not possible to put an aluminum frame under a C3. All I'm trying to wrap my mind around is a functional replacement, not necessarily an identical shape frame that I wouldn't lose concourse points at the next NCRS convention.

This is just a technical exercise here for an admitted geek.

Thanks,
Mike

Edit: Just got to thinking, my Featherlite trailer has an aluminum frame, carries the Corvette, tools, several sets of tires, and weighs less (@2700#) than the Corvette.
 
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Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?

Just a piece of hardware store shelf stock, for both metals....

both were 3/4" wide and 1/8" thick.......:eek:h:
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?

Just a piece of hardware store shelf stock, for both metals....

both were 3/4" wide and 1/8" thick.......:eek:h:

with a softer alloy, you probably would have been fine - the hardware stuff is great for tacking down carpet - not so good for anything else

To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?

Just a piece of hardware store shelf stock, for both metals....

both were 3/4" wide and 1/8" thick.......:eek:h:

with a softer alloy, you probably would have been fine - the hardware stuff is great for tacking down carpet - not so good for anything else

To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.

A 1950 Buick?? the type with the large round fenders and the ports on the sides?? YGTBFSM......got the car?? I can't even imagine WTF you would have to do to get one of them to run modern......

My father had a '49 Buick, the first car I have any recollection of, in the family, then he went to a '53 Packard Clipper, then a used '56 Caddy, then a used '59 Caddy that he had to set the garage door on top of the tailfins, the damn thing was SO long, Dad took a tape measure with him to check the length after that fiasco of a purchase.....:flash: been a while.....:cry:
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?

Just a piece of hardware store shelf stock, for both metals....

both were 3/4" wide and 1/8" thick.......:eek:h:

A large U shaped mount made with eighth inch aluminum?
 
Maybe 20 years ago, I had a boat that I put DPFI on it, ran it with a GM Grand Am computer, needed a X1 and X2 input to trigger the injectors....on a 4 cyl Volvo engine & I/O.......

so to make a bracket for the Infra red LED's that went from the block, out and around the crank pully and back, a large U shape, drilled a hole in the pulley flange so the LED's could talk to each other.....

the aluminum I used lasted maybe two outings, the silly shit shattered and broke like a piece of glass right next to the mounting bolts.....

I called up a Mech Engineer I used to work with, and asked him WTF.....

he just laughed and said that it was the nature of aluminum to do that and I had to switch materials to steel, so I did and no more troubles....

So aluminum shattered under vibration, I never knew that.....:hissyfit:

I would imagine the engine mounts would do that too for any chassis work....much less road vibration on the suspension....steering mounts??

:clobbered::nuts:

what alloy did you use?

Just a piece of hardware store shelf stock, for both metals....

both were 3/4" wide and 1/8" thick.......:eek:h:

A large U shaped mount made with eighth inch aluminum?

Yeh, It was bolted with two bolts to the iron block, went out and across the crank pulley and obviously did not touch the belts, I put a couple of intfrared LED sets where the pully flange rode by the part in front of the pulley, they looked at each other from sender to sensor, through a hole in the pulley, gave me a 5 volt TTL input source to tell the computer when to fire.....simple, really, except then the bracket broke, and edjemaked me on aluminum and vibrations, and shit.....left us on the water with an engine having more misses than hits....had to find a pole for my son to hold against the broken bracket so we could get back to shore......the aluminum shattered about 1/4" from the bolt on one end, the other end was not far away from failure either, ruined about 1/2 a day on the water, for the kids....oh well....:flash:
 
If the flex (fatigue) was kept to a minimum, I think it could be done.
Structural foam filled, and a full (bolt in, obviously) cage might be sufficient to prevent most frame flex assuming you arent running slicks.
Fabricating it would be another story... I think the C5/6 are hydroformed
 
Aluminum frame - why not

Many modern high end automobiles (and trucks) have aluminum frames and other stressed structural components. Aluminum is indeed different than steel with respect to fatigue life. Typically steel exhibits an asymtotic stress/cycle (S-N) curve where at some load (the asymtote) the fatigue life is considered infinite. Aluminum doesn't do that but as the stress goes down the number of stress cycles keeps increasing. The point is that more engineering is needed to produce a safe long lived design in aluminum than steel but aluminum is certainly a feasable materal for a frame.

IIRC 69427 has aluminum suspension pieces and all the chassis loads pass through those suspension bits to/from the frame so why can't the frame be aluminum.

There are a lot of really old aluminum aircraft still flying (i.e. DC3s are like 75 years old) and they log a lot of stress cycles on every hop. Good design recognises material limits.

Grampy
 
Semi trailers can be made aluminum, look at bulk tankers they carry 45k plus pounds.

Just think cost wise would be the downside to an aluminum frame is all.
 
..................
To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.

I'm only interested in a functional (but lighter) replacement. Nobody sees the frame once the body is installed.
 
..................
To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.

I'm only interested in a functional (but lighter) replacement. Nobody sees the frame once the body is installed.

I was thrown off-track with your comment about the NCRS... I admit to looking at the new C7 frame and wonder how hard it'd be to put under a C3 (but I'm sick that way)...
 
..................
To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.

I'm only interested in a functional (but lighter) replacement. Nobody sees the frame once the body is installed.

I was thrown off-track with your comment about the NCRS... I admit to looking at the new C7 frame and wonder how hard it'd be to put under a C3 (but I'm sick that way)...

I think you would find much what I did when I considered using the frame from my C4. For one it's wheel base is 1.8 inches shorter, Then the frame rail area under the doors is about 3.5 inches wider then a C3 frame.

however I wonder if the frame rails were moved in, then do a 1.8 inch stretch & trim and reinforce the A & B pillar areas if a C4 frame could fit under a C3 body.

The C4 frame has the same basic shape as a C3 frame but seems to be much stronger. As for weight I am not sure of the rolling C4 frame.

Companies stretch frames for limosines so I don't see why this frame couldn't be adapted to fit my C3 body

remains001_zps9e2522e8.jpg
 
..................
To the OP - I think the hardest part would be making the frame look stock. Aluminum can be tempered after being forged, but that would be an amazing bit of kit. That said, I suspect the issue would be stability of the material - the harder it gets the more crack prone it gets; and for a frame, you don't want deflection.

I'm building another car (50 Buick) and seriously considering building it with an aluminum frame and cage. It'd be banned at any track (as cages must be steel and only steel), but it'd be a blast to drive because it'd be a full sized car with a weight of around 3000 lbs. And I'd never race it (okay, maybe autocross because it'd be fun to do) it'd just be for fun and transportation.

I'm only interested in a functional (but lighter) replacement. Nobody sees the frame once the body is installed.

I was thrown off-track with your comment about the NCRS... I admit to looking at the new C7 frame and wonder how hard it'd be to put under a C3 (but I'm sick that way)...

I think you would find much what I did when I considered using the frame from my C4. For one it's wheel base is 1.8 inches shorter, Then the frame rail area under the doors is about 3.5 inches wider then a C3 frame.

however I wonder if the frame rails were moved in, then do a 1.8 inch stretch & trim and reinforce the A & B pillar areas if a C4 frame could fit under a C3 body.

The C4 frame has the same basic shape as a C3 frame but seems to be much stronger. As for weight I am not sure of the rolling C4 frame.

Companies stretch frames for limosines so I don't see why this frame couldn't be adapted to fit my C3 body

remains001_zps9e2522e8.jpg

it could, but it probably wouldn't be any lighter
 
If the frame were caged and the body panels bonded on, you could end up with a very stiff structure (ala ZO6 aluminum frame)

450f7f9d4d5ce2.jpg
 
Here's why I was looking at the C7.... it looks like they moved the passenger compartment back towards the center of the rear wheel - the issue with the C5/C6 is the passenger compartment is too far forward (IMO) to adapt

2014-Chevy-Corvette-C7-Aluminum-Frame-INDUSTRY-H.jpg


thus it'd be easy (lol) to swap that frame into a C3 :sweat:
 
If i were able to fab an aluminium frame, id use 7075 aluminium.
I use 6061 aluminium frames on my rc cars. They bend often. Because of the greater cost, no one offers 7075 frames.
However there are chassis upgrade pieces in 7075 and those are usually half as thick as the t6061 pieces and just as strong.

Sent from my dumb 4g motorolly
 
strength vs stiffness

Ideally the chassis should be a stiff as possible. This design goal is usually expressed in torsional stiffness. The C3 has some severe constraints with the basic body on frame architecture and ladder frame. Aluminum is about 1/3 the weight of steel. Some alloys like 2024 and 7075 can be stronger (higher tensile strengths) than the OE low carbon steel frame material. These stronger alloys come with fabrication and corrosion issues. The larger issue is that aluminum is also only about 1/3 as stiff as steel. To replicate the OE frame in aluminum would produce a very flexable piece. Working with aluminum, if you wanted to keep the same basic design you would have go to larger sized members to regain the stiffness but there is not room to do that in a C3. Simple increases in wall thickness are not efficient and won't save the desired weight. To be successful the aluminum chassis would have to be more three dimensional like a tube frame car or the newer C6/7.

Grampy
 
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