So what are the pros and cons to the Corvette leaf spring suspension versus say a Camaro strut/multi link setup? What setup has the best characteristics for road race tracks. Inquiring minds want to know.

 

Head over to the Autocross and Road Racing forum. Between the stickeys and individual threads you'll be reading for hours!

HTH, and have a good one,
Mike

 

Mike thanks for your reply. I just didn’t seem to find an answer to my question in that forum section but maybe a moderator can move this over there and I will have a better chance at an answer.

 

Well, suspension setups are really complex, not only because the science is complicated, but the "feel" of a suspension setup is unique to each of us.

I'm guessing from your original post that you're coming from a solid axle type background (i.e. 4th Camaro). I wouldn't try to figure out pros/cons between different suspension configurations on different platforms; there's just too many optimizations made in the platforms to try to figure things out.

I will say this: stock Corvette suspension is more capable than 90% of us drivers, me for sure!

Have a good one,
Mike

 

Thanks Mike. Not really looking for all that technical mumbo jumbo just a basics on the Corvettes leaf spring setup compared to a strut trailing arm suspension. GM must have its reasons why it has stuck to this for so many years. Just a suspension for dummies question.

 

ncstingray
Suspension set up is a science and an art and a language I can't comprehend.

I will offer you this:

My '16 Z51 M7 with magride, completely stock but for brake pads and fluid was 4 seconds faster/ lap at Watkins Glen than my 565 hp supercharged Mustang Cobra IRS with full coilover suspension,and Torsen T2R diff, off-road xpipe on R compound Nitto NT01's.... without even trying hard.

And quiet and comfortable on cross country road trips

 

UGHH

 

Three reasons come quickly to mind: cost (the design is well understood), weight (both overall and lower c.g.), and support strength (reacting all the weight from the bottom center of the car at a naturally strong point as opposed to the shock towers).

BTW, all of the "mumbo jumbo" (which I agree with you on) IS suspension for dummies!

HTH, and have a good one,
Mike

 

The transverse leaf spring allows a lower chassis structure (there is no "strut tower")

 

No way to get around the technical mambo jombo if you want a true answer.
Unlike the news everything can’t explained in a 30 second sound bite.

http://www.corvetteonline.com/tech-s...vers-vs-leafs/

 

What do you think the shocks bolt onto?

Back to OP question::

A leaf spring can have all the normal characteristics of a coil spring.
But a leaf spring can be engineered to have a bit of energy absorption as it bends (or not!) whereas a soil spring cannot.

 

I think of a shock tower as a structural member of the chassis; i.e. not only is it strong/stiff enough to transfer the transitional loads of the shock, but also support the weight of the car on that corner. A separate leaf/spring system doesn't have to do that.

That said, starting with the C5s, A LOT of folks have ditched the transverse leaf for a coil-over setup, and I've not heard of any cracking in the upper mounts. So, while it technically doesn't have to be strong enough, ours apparently are.

Have a good one,
Mike

 

OK, I'll take a crack at a simple answer:

The type of spring and the link set up are really two separate subjects. For example, people have converted factory front leaf spring Corvettes to coil springs, and you can convert a C3 factory front coil spring Corvette to a transverse leaf spring.

Each link and spring setup has its own pluses and minuses.

 

In summary the Corvette suspension is better than the Camaro’s suspension. This is why:

The leaf springs aren't what make the Corvette suspension different than the Camaro's. It is the double A arms (double wishbone) located at each corner. One of its primary benefits is the increase of negative chamber as a result of the vertical suspension movement of the upper and lower arms. This translates to better stability properties for the car as the tires on the outside maintain more contact with the road surface. Handling performance also increases. The double suspension system is much more rigid and stable than other suspension systems, thus you would realize that your steering and wheel alignments are constant even when undergoing high amounts of stress.

Moving on to the drawbacks of the double wishbone suspension system, it is normally bugged by cost issues as it is a more complicated design to produce. There are many parts to the system, and thus every time any of these malfunction of fail, your whole system fails. Repair, modification and maintenance costs and complexities for double wishbone suspension systems are normally higher due to these reasons. This suspension system also proves to be flexible for design engineers, as the arms of the system can be fixed at different angles to the surface, parameters such as camber gain, roll center height and swing arm length can be determined and designed flexibly to suit and road surface in condition.

The leaf spring is a cost effective way to implement the spring in such a situation, but like the C2 and C3 cars the spring could be mounted inside the A arms with the shock running up through the spring. Or a torsion bar could be tied into the lower A arm like the 1500 Series GM Trucks have done.

The McPherson Strut was invented by a Chevy Chief Engineer and it is named after him. GM didn't build the car the strut was supposed to be used in so the guy went to work for Ford and was introduced in some Ford products in the early 50s.

To be really successful, the MacPherson strut required the introduction of unibody construction, because it needs a substantial vertical space and a strong top mount, which unibodies can provide, while benefiting them by distributing stresses.

The strut will usually carry both the coil spring on which the body is suspended and the shock absorber, which is usually in the form of a cartridge mounted within the strut (see coilover). The Camaro has a unibody while the Corvette has a body on frame construction so it doesn't have a way to provide the extra support required by the upper end of the strut.

The strut can also have the steering arm built into the lower outer portion. The whole assembly is very simple and can be preassembled into a unit; also by eliminating the upper control arm, it allows for more width in the engine compartment, which is useful for smaller cars, particularly with transverse-mounted engines such as most front wheel drive vehicles have. It can be further simplified, if needed, by substituting an anti-roll bar (torsion bar) for the radius arm. For those reasons, it has become almost ubiquitous with low cost manufacturers. Furthermore, it offers an easy method to set suspension geometry.

Many modern implementations replace the lower control arm by a wishbone. An anti-roll bar is optional and if present is attached by a ball-jointed rod to the spring-damper or by a ball or elastomerically jointed rod to the wishbone.Although it is a popular choice, due to its simplicity and low manufacturing cost, the design has a few disadvantages in the quality of ride and the handling of the car. Geometric analysis shows it cannot allow vertical movement of the wheel without some degree of either camber angle change, sideways movement, or both. It is not generally considered to give as good handling as a double wishbone or multi-link suspension, because it allows the engineers less freedom to choose camber change and roll center.

MacPherson struts have some other drawbacks. Being a long, vertical assembly, you would encounter difficulties if you lower your car as there may be collision with the structure of your car. Thus they do not work well with racing cars that are normally lowered. The MacPherson struts also have problems working with wider wheels that have increased scrub radius, where you would need extra effort to navigate your car in this situation.

Despite these drawbacks, the MacPherson strut setup is still used on high performance cars including manufacturers such as Porsche, Mercedes-Benz, and BMW.
Porsche 911 up until the 1989 model year (964) used a similar strut design that does not have coil springs, using torsion bar suspension instead.

I picked up most of this by doing a Google search on the internet. The double wishbone suspension on the front and rear of the Corvette is just a better design than a strut suspension and is what designers choose when they design a race car from the ground up.

Basically, Jeremy Clarkson had no idea what he was talking about when he made fun of the C6 Corvette leaf springs.

Bill

 

You could have stopped right there. Funny guy, but has a much better opinion of himself than others have.

Have a good one,
Mike

 

Take a look at the Porsche GT2 RS that set a record 6:47.25 run on the Ring. It has a MacPherson strut front suspension(coil springs) and a multi-link rear suspension with coil springs. I don't believe any Corvette with leaf springs have beat that time.

And also look at the AMG GT R who has turned in a 7:10.92 time on the Ring with it's coil over suspension. It did that with only 573 horsepower with the engine located in front of the driver, just like the Corvette 650 HP Z06. I don't believe any Corvette with leaf springs have beat that time.

 

Bill that was an absolutely fantastic reply and I thank you very much for giving the basic outline of both. I knew there had to be a reason the Corvette has stayed with this design all these years. I have driven many cars at VIR and so far the Z06 has been the best handling of all.

 

Hey Joe I would suggest selling your Corvette (if you own one) and buy a Porsche and go hang out on Planet 9, Rennlist and such forums. I will drop in over there from time to time and see how you are doing. Thanks

 

I just got the time to read through this; thanks, Bill, I just learned some things.

Have a good one,
Mike

 

My bet is that a composite transverse spring, (there are no actual leaves of springs in there, at least for the c7), is lighter than two steel coils, and takes up less space around the wheel.