Suspension Dimensions

[68RS350]

Im lookin to design a subframe for my 68 Camaro. I have Solidworks and Pro Engineer and I was going to model it up in either one of the prgrams and I was wondering if anyone had dimensions for the 4 subframe mounting locations and the center distances for the lower control arms. Or if anyone knew where i could see a copy of the old drawings from chevrolet or what. I was planing to use the DSE Coilover conversion for my upper mounts and then design the rest of the frame. So if you guys have any pointers or inputs feel free to chime in. I want to try and use stock components so i can use dse control arms and sway bar and stuff. Thanks in advance!

[Goatman]

There are enough people that maufacture them on this forum that I wouldn't think it would be worth the effort....

[68RS350]

Which one of them uses the aftermarket control arms and sway bar? I dont know of any except for the DSE subframe and that is $6700.00.

[Goatman]

I doubt very much anyone who spends all that time designing a new one would use the stock stuff.........


Do a search here, there must be 5 companies that to 1st gen F-body stuff.

[baz67]

Why do you want to design your own frame and how much do you know about front suspension geometry? It is great if you want the challenge of making your own frame. However, it is not as easy as getting a few pickup points.

[68RS350]

IM not using the stock components im going to use a DSE Sway Bar, DSE Control Arms, and ATS Steering Link. And im using the stock goemetry. That is why i am using the Coil Over conversions because I can locate the upper mounts from the engine mount holes because of the bracket with the kit. Alls I need is to find out how to locate the holes for the lower control arms.

[Beach Cruiser]

Is this what you are after? It was made by Wayne Due before he closed shop.

[engmatt]

I would like to fab my own subframe also. I have a complete set of Corvette C-4 components. I was going to purchase a WD subframe, but I guess I procrastinated too long.

[Beach Cruiser]

ENGMATT, I'm doing my own Sub using C4 components, you can follow some of my progress over at Laterial-g.net. Seach for my ID.

[J68Bird]

I'm getting ready to start cleaning up my subframe and I could get you some accurate dims if you need them. I use ProE all day long and have modeled the IRS setup that I'm putting in my Firebird. I have to add Scot & Twin Turbo hooked me up with the C3 rear models. (thanks Guys) I just put it all together with my rails and air ride. It took a while but I worked on it when it was too cold to be out in the garage. At least I felt like something was getting something done. Now that the weather is getting better I'd rather be cutting & welding than on the PC.



J. Clear
68 Firebird Conv.
455/4spd

[Samckitt]

Hey J-bird :-) Show me a pic of your model fromteh back side so I can see how you made the brackets for the crossbar. Please.... One of the arms on my batwing is bent & I either have to buy a new one ($750 for a Dana44) or make something like you have.
Thanks,
Scot

[J68Bird]

Scot,
Here's a pic of the back. If you need any more info let me know.
I might be changing the position of the rear shocks. I don't like the way I have to angle them back for clearance.



J. Clear
68 Firebird Conv
455/4spd

[Twin_Turbo]

Looks like the carrier mounts to the original lid which has 4 bolts for a carrying crossmember.

Scot, you can just cut the batwing off and use the spring pad for mounting, I assume you are not going to use the leaf spring anyway?

Nice model since you're doing a custom IRS anyway, may i suggest you use the trailing arm as forward links and leave the front floating, then add a toe control rod to the rear (or use paired camber rods) for toe control? The C2/C3 corvette trailing arm IRS has terrible toe control, it changes all through the suspension travel.

[J68Bird]

68RS350
Sorry for hijacking your thread.


TT
I like your idea, unfortunately I only understand about half of what you're saying. I'm pretty good at modeling & fabricating, but my knowledge of suspension design is not too good. I'd really like to incorporate this into my build. Would you have a pic of this type of setup, or maybe a quick sketch? If I see it I think I can build it. Tomorrow, I'm going to look at, and maybe borrow some components from a wrecked Enzo. I'm thinking about utilizing (copying) the horizontal shock mounting setup they use. I'll start a new thread when I get the info.

J. Clear
68 Firebird Conv
455/4spd

[Twin_Turbo]

I don't have a pic. I will try to explain.

Your toe is set by the forward bushing on the trailing arms. You shim this left and right in the attackement point. The trailing arm however not only moves up and down but also sideways when going through susp. movement. This because the effective horizontal component of the halfshaft changes with it's angle to level. This means that the toe changes from it's max setting w/ horizontal halfshafts to less toe and depending on the initial setting even toe out.

The solution for this is using a toe control rod and using either a floating trailing arm, or even better a set of dual forward rods like the C4 suspension has.

Both the C4, the guldstrand/riley&scott and greenwood setups use this. The C4 and Greenwood use a toe control rod (although the stock C4 one isn't particularly perfect when it comes to geometry, it should be in harmony with the halfshafts yet the C4 uses a central mount on the diff lid and this gives long toe control rods that control toe but have a flaw in doing so, the less the susp. moves the less the angular change and thus the horiz resulting component and the less the toe change is)

Guldstrand uses 2 lower strut rods and the setting of the rear vs. the fronts gives you the toe. This is a perfect solution, as is the Greenwood one which, unlike the C4 DOES use rods that are in compliance w/ the geometry of the halfshafts (in the same plane and pivoting/hinging at the same lengs and locations as the u joints)

Here are some pics of the guldstrand and under that the greenwood setups. Also included is a pic of my old setup but it's missing the toe control links in those pics (I dropped it and built dual a arms instead) but you can see the forward rods.

Guldstrand

the "gray" thing is a stand, not part of the suspension.

Greenwood




mine: