Doesn't anyone have, or know where I can get CAD files for the C4 Corvette's frame and suspension?

I found lot of the C4's frame dimensions in the FSM

I really want to input the whole suspension into a computer.

I'm going to coil overs and this would really help pick out the rate.

Also I'm thinking of making some modifications.
C4's are camber challenged, but just laying the upper a-arms against the frame doesn't do it. I've tried that, and it compromises braking too much.

If anyone has there car apart in the garage, can you measure the easy stuff?
A-arms dogbones etc.
I can then start work on the CAD file.
I'll provide the CAD file to anyone who helps me out.

BTW I really hope the upper a-arms in the front aren't pointing DOWN while at rest.
That would explain a lot!

Hi Brian,

My front suspension is currently apart, so I can basically measure anything you like.



Just let me know. What CAD program will you be using?

Regards,

The end goal is to put the geometry into a suspension analyzer.

Something like this:

[url]http://www.mitchellsoftware.com/prod01.htm[/url]



I have SolidWorks, and that may handle what I need to do.

What I need measured is geometries that are critical to how it moves.
ie) center to center distances, but not thicknesses.

If it would help I can make drawings showing what I need.

Items like the dogbone bushing center-to-center lengths should be easy to measure.

On the a-arms for instance, I need the center of the bushing hole to the center of where the ball joint pivot moves, which will be hard to measure. I need to know where the rollbar is connected, where the spring hits, where the shock is connected. These will tell me what spring rates to get.

This is no small task, but when it's done, I'm hoping to come up with some simple solutions to some of the handling issues we have.

[QUOTE=SuperL98;1563496247]Man that was a long time ago :D
The images still seam to be on my CF homepage, but they don't link anymore?
Haven't logged in for awhile...
logged in and now they seam to have come back up :rolleyes:

I did lay the rear out in solidworks and had started on a design with an adjustable control arm bracket, but lets just say I lost the files during an "unplanned" carear change :lol:
Haven't had time to do much with that since.

P.S. I did my measuring with machinist rulers crawling around on the gagrage floor, just to get the general layout. I wouldn't be machining parts based on them ... without verification ...[/QUOTE]



This picture is a BIG help.



Combine it with this one


And a lot of the rear suspension behavior can be done.

I agree, the ball joint pivot points will be tricky to measure. I think I may be able to rig something up that will hopefully provide adequate accuracy.

Also where the spring contacts the lower a-arm. But if you are going with coilovers the spring contact point will be the shock mount, right?

I think this is a very interesting project.

Can you import Inventor or ACAD files into Solid Works?

Interesting ...

ACAD?
Sure no problem!

I want to get the compete stock geometry down before modifying it.

That way I can measure the stock ones and see how good my model is.

Thus wanting the stock spring positions.

Again thanks.

The 1st thing I want to do is fix that front geometry.
The top a-arm should point up, not down at rest. So either the balljoint needs to go up or the frame side needs to go down, or both.

The second thing I want to fix is that rear geometry. The dogbones are way too short!
I don't know how many here realize it, but GM actually ripped off Dick Guldstrand's rear suspension design for the C3 when they built the C4. The trouble is the bean counters got a hold of it and messed it up in the process! Take a look at the dogbones, they run all the way to the back of the upright, thus making them at least twice as long. Also instead of a toelink, he has two beafy locating members spaced equally apart and on the same plane.



I might acually just buy his upright and adapt them to the C4.
Not only would I get the better geometry, but I'd get the beefier drivetrain, and cheaper bearings.

BTW does anyone have the front pic to go with this one?

I used to have it but now I can't find it

I have that front pic on my home PC. I'll post it when I get there.

Whipped this up today for starters. Brian I can send you the .dwg file if you like. If you think you can use this one I can draw other views of the a-arm. Dimensions in mm.

This is all I have that may be of any use to you, including those front suspension shots. I will check my Corvette specs at home and see if there's anything worth scanning. Hopefully one of those side view diagrams. Bogus may have some of this too in his "Corvette from the Inside" book.

http://home.san.rr.com/khastings/temp/ZR1suspensionCOMBOas2.jpg

http://home.san.rr.com/khastings/temp/ZRchassis-brochurePIC.jpg

Some spring rates and roll stiffness mentioned in here:

http://home.san.rr.com/khastings/temp/fiberglass%20spring.gif


My 85:


http://home.san.rr.com/khastings/temp/vette%20007.jpg

http://home.san.rr.com/khastings/temp/susp2.jpg

Quote:

Excellant!

So long as the dim's are on the drawing, I shouldn't need the .dwg
But here's my email anyways. swiftwood@aol.com

If you can get the elevation dim's that would be great.

CC,
Thanks for the photos.

They're a big help, drawings are the best, since I don't have to compensate for foreshortening. But I can still get a lot out of them.

Here's the stock subaxle.


And I've started on the upright.


Some dim's you can get off the net.


Once we have them into a database, we'll really have something for this site to share with the Corvette world

No problem, I'll do those tomorrow.

1st crack at the C4's frame.

This doen't need to be the that accurate, so long as the suspension pick-up points are. It's more for reference.

GM's


Mine

Don't forget the trusses up front of the A pillars.

And doncha know, you can't post those 3d renders without doing a stress diagram first...

This one may not look pretty but the relevant dims are there I think.



Nice job on the frame by the way.

Thanks Hilmar

Quote:

You can if you doing a travel analysis :tongue:

Upper a-arm

Cool ...

excellant

Keep'em coming

more

Brian do you have the suspension mounts on the frame measured up? Just wondering if I can start putting the car back together, lol.

Now that you meantion it

Actually if you could get those too, I'd then have all the zero scrub measurements.

BTW eDrawings will let you look at all the SolidWorks parts and it's FREE
http://www.eDrawingsViewer.com/download

Quote:

One question
How do you compress the front leaf spring for assy?
I will be rebuilding the front suspension on my 84 soon. The only thing holding me back was compressing the leaf spring without using some exotic tool.

You don't need to compress it.

Seperate both knuckles from the lower ball joints and the spring should slide in. If it doesn't clear the ball joints, try removing the entire lower control arm on one side.

Then when it's in place, put a floor jack under the lower control arm, jack it up until you can bolt the shock in place. The front shocks limit the suspension travel and also act as the bump stops.

I'll be replacing the bushings in the control arms also, so I'll have everything off the car, just like you picture.

Thanks for the info

Tom

Sorry on the model delay.

I'm still getting settled in PA, I'm on a contract for Lycoming engines.

I brought everything I need, well except my car.

I´ve been lazy, but here are some more.





Dims are hard to see on this one. Top to bottom 700 (upper a-arm spacing), 946 (shock mounts-these were difficult to measure so I´m not to certain about the accuracy), 610 (lower a-arm spacing)

Another excellant job.

Yes, having the engine there makes is a real PITA to measure.

They're parallel to the centerline? That's surprising.

How far up does the shock mount come in this picture?

697 mm. I just realized that the dimension for the spacing of the upper a-arms is not entirely correct. The distance between the frame mounts is 700mm. This is what it should look like:



Of course each car's alignment differs so the 13 and 18 will most likely be different. (And I expect it will be different on mine after it gets aligned after lowering)

I'll try to get a better measurment of the shock mount, it will be important for spring rate calculations with coil overs.

I knew about the spacers, I'm just surprized the actual mounts under them were straight. That said, I was going to ask for the spacer measurements next.

again thanks!

Next step is to combine all the sketches into one drawing and see if everything adds up ok.

1st having the flu $uck$

that said I made a relational drawing for the links.
That way I can have one part file with many derivations for all the various links in the back end of the car

Hello people

1st sorry for the delay, the contract in PA took up a lot of my time, but that's over with now.

2nd, Gary lent me a rear upright for me to measure up.

i'm looking for the C6's suspensions cad file. do you know something about?

Geez that's some high tech stuff.......I wonder where Hilmar and Sprint wandered off to........

I got them model done, if anyone is interested

Bogus,
Could you host the file here, so I don't have to keep posting it on Usendit.com (it's kind of a BIG file)

for the C6 stuff, GM actually released it.
You need to be a SEMA member to get it though.

I guess I wandered to a new account as my old account stopped working :-)

I would be interested in seeing the model Brian

Here's a pic
[IMG]http://i242.photobucket.com/albums/ff87/swiftwood/Corvette/hubs/suspension-2.jpg[/IMG]

Rest of the pics here.
http://s242.photobucket.com/albums/ff87/swiftwood/Corvette/hubs/

What kind of CAD software do you have?

Quote:

If you prefer your old account, either send Andy or myself a message and I'll reset the password.

Matthew

Wow there is a ton of work that you have put into ths very impressive.

I have an old version of Inventor, 8 I think it is.

I can host it, please email it to andy@corvette-guru.com.

I will upload to a public area and link it here.

As for SEMA and the suspension files? I have to confirm, but I think it's for members only... I will check.

Oh, on the frame... there are no suspension pickup points, to be honest. Ok, the trailing arms, but they fit to a bracket. The rest are on the backbone chassis.

I uploaded it to a folder on YouSendIt.com

Let me know if you get it Andy.

It's an IGES files.

Most CAD packages can read it, though you loose the parametrics (ablility to change dimensions)

If you don't have a CAD package then you can use eDrawings, FREE from SolidWorks to look at it.

Resurrecting this old thread


In order for more people to have access, I've uploaded my SolidWorks model of a C4 suspension (late model) on 3DContentCentral

http://www.3dcontentcentral.com/parts ... x?id=443356&catalogid=171


Download

It is to model the pickup points to study rollcenters, anti-dive angle etc.
It is NOT meant for component fitment
Some parts are greatly simplified Links are modeled as rod ends as I have rod ends on my 1995 Corvette

I'd also uploaded a model of a C3 Stubaxle

http://www.3dcontentcentral.com/parts ... x?id=442353&catalogid=171

Attach file:

---

  suspension.jpg (0.00 KB)