C5 Corvette Suspension Geometry

[BBShark]

I am interested in using C5 control arms, front and rear, on a project car. I would like to find the stock control arm pick up (attachment) points for the C5. Specifically interested in anti-dive angle for the front but could use any info. I do have the stock settings for caster and camber.

[Marcus SC&C]

Unless you`re building a lightweight front mid engine,rear transaxle sports car the C5 geometry will be less than ideal anyway. C5s have super mild camber gain and almost no anti-dive which is fine for a,well balanced lightweight car but less than ideal for the cars we deal with in the PT world. Also bear in mind that GM engineers designed those aluminum arms to be as light as possible and still be strong enough for a light weight sports car with minimal weight transfer under heavy braking etc. Weight was such an overriding concern in the C5 program that the original spindles failed in track testing and had to be beefed up. Also consider that aluminum has a finite fatigue life and that it`s usable lifespan is dramatically reduced if it`s pushed beyond it`s design specs. I`m just sayin. Mark SC&C

[Lowend]

...not to mention that the C5 front upper a-arms are really poorly designed with their pressed in rubber bushings and the 2 mini-cross shafts (for lack of a better way to describe them).
Inherently unstable in stock layout.




Works really well in the C5, but I would not design a car around it.

[WS6]

How is it any more unstable than if it had a full cross shaft running through? Or is there more to it than just the minishafts?

[79T/Aman]

two separate mounting points move independently and are not as stable as a cross shaft

[Lowend]

It's not just that...
The "cross stubs" are mounted by being pressed through the rubber bushing from one side to another. This means that the bushing is inherently soft and must be flexible enough to do this.

A few years back I was working with a vendor to develop a del-a-lum bushing for use in a World Challenge C5-R. We could not come up with a good solution for this without using a spherical bearing in the upper a-arm.

Man I miss that car

[WS6]

I see. Thanks for the clarifications.

[BBShark]

Unless you`re building a lightweight front mid engine,rear transaxle sports car the C5 geometry will be less than ideal anyway. C5s have super mild camber gain and almost no anti-dive which is fine for a,well balanced lightweight car but less than ideal for the cars we deal with in the PT world. Also bear in mind that GM engineers designed those aluminum arms to be as light as possible and still be strong enough for a light weight sports car with minimal weight transfer under heavy braking etc. Weight was such an overriding concern in the C5 program that the original spindles failed in track testing and had to be beefed up. Also consider that aluminum has a finite fatigue life and that it`s usable lifespan is dramatically reduced if it`s pushed beyond it`s design specs. I`m just sayin. Mark SC&C

I am considering building a lightweight car for track days. Probably a C3 Corvette body. This would be a stripped car probably about 2800lbs. The suspension components for a C5 and C6 have been around for more than 10 years now and I am unaware of failures of these components due to fatigue. Any information on the C5/6 geometry would be greatly appreciated.

[Marcus SC&C]

There certainly shouldn`t be any problem with fatigue failures on a car lighter than a C5 or C6. Fatigue related failures occur over time and parts like the lower A arms have only been used in non stock applications for a few years. I`m not saying any of them will fail but I`m wary of it because of the reasons stated. Mark SC&C

[JEFFTATE]

Hmmm , Interesting .
So what would work better ?
Global West ?
Detroit Speed ?
SPC ?

[Lowend]

It's really application specific.
In a perfect world you would design a tube frame and chassis and than build the body around it... but the world ain't perfect.

Honestly with a few aftermarket parts the C3 Corvette platform is quite good

[Bjkadron]

I know this is an old thread but I'm also interested if anybody has any info...

I'm building a full tube frame and moving back the engine so My duster wont have a lot of weight on the front(I'm shooting for somewhere around 48/52 f/r ). and I'm lightening it so it will be about 2600-2800# total. So maybe corvette suspension will be right for me? if it is That would save me the time that it would take to design a new system.

thoughts anyone?

[silver69camaro]

It's funny how this thread is bad-mouthing C5/C6 parts. Here's what I think:

1. C6 parts are strong...very strong. I dare anybody here to try and break them. The weight of these pieces go great lengths in helping our cars perform better...and ride nicer.
2. Upper cross shaft movement is extremely minimal in everything except all-out racing applications. NOBODY here will be able to stress these to their limits. NOBODY.
3. The geometry can be easily modified for more anti-dive (not a whole lot is needed), radical camber gain, and still have a fraction of the roll center migration of any modified F-body suspension.

Those who are in the "know" of suspension design understand the C5/C6 design is hard to beat. Right up there with the most exotic Euro cars.

[BBShark]

It's funny how this thread is bad-mouthing C5/C6 parts. Here's what I think:

1. C6 parts are strong...very strong. I dare anybody here to try and break them. The weight of these pieces go great lengths in helping our cars perform better...and ride nicer.
2. Upper cross shaft movement is extremely minimal in everything except all-out racing applications. NOBODY here will be able to stress these to their limits. NOBODY.
3. The geometry can be easily modified for more anti-dive (not a whole lot is needed), radical camber gain, and still have a fraction of the roll center migration of any modified F-body suspension.

Those who are in the "know" of suspension design understand the C5/C6 design is hard to beat. Right up there with the most exotic Euro cars.

I'm glad to hear you say this!

I don't know how this thread turned into the (real or imaginary) inherent weakness of C5/6 suspension components. I asked this question in August looking for the pickup points for a C5/6 suspension. Since then I've been able to locate that information.

[SDMAN]

It's funny how this thread is bad-mouthing C5/C6 parts. Here's what I think:

1. C6 parts are strong...very strong. I dare anybody here to try and break them. The weight of these pieces go great lengths in helping our cars perform better...and ride nicer.
2. Upper cross shaft movement is extremely minimal in everything except all-out racing applications. NOBODY here will be able to stress these to their limits. NOBODY.
3. The geometry can be easily modified for more anti-dive (not a whole lot is needed), radical camber gain, and still have a fraction of the roll center migration of any modified F-body suspension.

Those who are in the "know" of suspension design understand the C5/C6 design is hard to beat. Right up there with the most exotic Euro cars.

-----------------------------------------------------------------
Agree 100%. The C5/C6 suspensions are light, strong and have world class geometry. And thats why I had my A/M Max-G frame made with the C5 parts.

[parsonsj]

I'm with Matt. Those parts have impressive amounts of engineering and failure mode analysis behind them.

The only drawback I see is the inability to service the upper balljoint. If the ball joint fails, you have to buy a new upper control arm/upper bj/upright assembly.

The other weak point is the wheel bearing inserts, but the aftermarket has stepped to make durable long lasting bearings. See Steve Rupp's Defender edition thread for more information on that.

jp

[silver69camaro]

The only drawback I see is the inability to service the upper balljoint. If the ball joint fails, you have to buy a new upper control arm/upper bj/upright assembly.

Agreed. Also, in order to remove the hub, you need to disconnect the LBJ. Oops!

BBShark, I have that info. It's not the geometry we use at AME, but the stock pivot points. PM me if you'd like the info.

[WS6]

vansteel makes hubs for the C5/6 that have tapered bearings and are serviceable for anyone wanting a better hub than stock. Their prices are pretty good as well.

Also, there's a J-tool that's specifically designed to pop the ball joints apart and not damage anything. I use it all the time when doing work on C5s. Never an issue putting it back together or taking it apart.

[JMarsa]

vansteel makes hubs for the C5/6 that have tapered bearings and are serviceable for anyone wanting a better hub than stock. Their prices are pretty good as well.

Also, there's a J-tool that's specifically designed to pop the ball joints apart and not damage anything. I use it all the time when doing work on C5s. Never an issue putting it back together or taking it apart.

So your debunking the myth that the spindles are not rebuildable?

--JMarsa

[LateNight72]

If anyone gets bored.

http://www.mae.wmich.edu/faculty/hat...Anti%20pJZ.ppt