Can anyone explain what independent suspension is? I'm guessing that a solid rear axle is NOT independent, but what is exactly? Do Fieros have independent suspension or what? IIRC 84-87 Fieros had the front suspensions out of two cars, are front suspensions usually independent so the Fiero is independent? Also, what are the pros/cons when compared with solid axles and such? There's just some things you can't really find out on your own, you've gotta ask .

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http://members.cardomain.com/tinton

independant suspension is when the movement of one wheel does not affect any other wheel.
yes, Fieros are independant front & rear.

quote Originally posted by Pyrthian: independant suspension is when the movement of one wheel does not affect any other wheel. yes, Fieros are independant front & rear.

I kind of thought that was the case (1 wheel doesn't affect movement of another) but I didn't know the types of suspensions that had that. Also, in Fieros, independent suspension is never mentioned. Ever. So, is it superior to...."dependant" suspension?

I would think so..when ya think of "dependant suspension", think of a solid axel going from one side to the other... like in big trucks... one side goes up, the other goes down...

You'd rather one wheel not effect the other when goin' along bumpy roads...


Oh, found a nice link w pics:
http://www.procarcare.com/icarumba/resourcecenter/encyclopedia/icar_resourcecenter_encyclopedia_suspsteer3.asp#rear

[This message has been edited by FieroRumor (edited 06-26-2006).]

If you can get a hold of it, I recommend Herb Adams "Suspension Basics" (or something like that). It's a good/easy read that explains all of the different types of suspensions, and their pros and cons.
If I recall correctly, the inherent advantage of an independent suspension is that on bumpy surfaces, particularly on a curve, the motion of one wheel does not affect the camber of the opposite wheel, thus affecting traction.

Bob

both live axles and IRS (Independent Rear Suspension) have their pros and cons, just like anything else.

quote Originally posted by Jermz238: both live axles and IRS (Independent Rear Suspension) have their pros and cons, just like anything else.

what are the pros of solid axles? they only thing that comes to mind is maybe if there was a 100% flat surface to race upon.
well, maybe just the mechanical simplicity of it?

quote Originally posted by Pyrthian: what are the pros of solid axles? they only thing that comes to mind is maybe if there was a 100% flat surface to race upon. well, maybe just the mechanical simplicity of it?

I remember on the History Channel on a documentary of the army jeep, they mentioned that the later models with independent suspension would roll over often when the tires left the ground, because the suspension goes limp due to gravity, and the bottoms of the tires got closer, so when it landed, it rolled. The solid axle stays rigid all the time, so that's a pro. It's also cheaper to produce than an independent.

Here's a couple of articles to get you started.

http://www.automotivearticles.com/Suspension_Design_Types_of_Suspensions.shtml

http://www.automotivearticles.com/Suspension_Design_2.shtml

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Notchbacks RULE

"Let a man drive a Fiero and he'll own one.
Teach a man to fix a Fiero and he'll own eight....errr...nine."

quote Originally posted by Pyrthian: what are the pros of solid axles? they only thing that comes to mind is maybe if there was a 100% flat surface to race upon. well, maybe just the mechanical simplicity of it?

I have also heard that it is easier for a car to hook up at the drag strip with a solid axle. At least front engine RWD cars. A few years back I read that some Mustang owners didn't want IRS on the Cobra because of that.

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NIFE

98 Grand Prix GTP Black
88GT Silver- bone stock (Sold)
87GT Blue- 3.4 roller cam, coilovers, 88 cradle swap, many other mods
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quote Originally posted by Dough19: I have also heard that it is easier for a car to hook up at the drag strip with a solid axle. At least front engine RWD cars. A few years back I read that some Mustang owners didn't want IRS on the Cobra because of that.

QFT, less moving parts = less stuff to break under extreme load

FYI Your Camaro you just sold did NOT have an independent rear suspension.

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Tim
Red 88 Formula Auto 2.8 100K+ Miles

The problem with political jokes is...they get elected!

quote Originally posted by FrugalFiero: FYI Your Camaro you just sold did NOT have an independent rear suspension.

Yeah, it has a torque arm in the rear and a "short/long arm (SLA)" front. What does that mean? Is that double wishbone?

quote Originally posted by Pyrthian: what are the pros of solid axles? they only thing that comes to mind is maybe if there was a 100% flat surface to race upon. well, maybe just the mechanical simplicity of it?

IRS is better for road racing and ride comfort. Solid axle is better for drag racing.

The later Mustang Cobra R had an IRS that helped it a lot in road racing, but actually hurt it on the drag strip. The new Mustang went with a solid rear axle because Cobra R drivers complained the IRS had wheel hop problems on the drag strip. GTO owners have the same issue.

quote Originally posted by Pyrthian: what are the pros of solid axles? they only thing that comes to mind is maybe if there was a 100% flat surface to race upon. well, maybe just the mechanical simplicity of it?

One of the pros of a solid axle is ground clearance (if done properly), particularly for SUVs. Take for instance a Jeep Liberty doing some rock climbing. If it had an independent suspension, if one side of the truck went up on a large rock or something, the wheels on that side would go up but drop the height of the middle of the car. In a solid axle setup, the entire truck is lifted up. Hence the ground clearance also goes up. A solid axle is also much stronger as there is no CV joint required between the differential and the wheel so one less thing the break due to high torque. Hence most drag cars and big trucks use solid axles.

The advantage of independent suspensions would be in the handling department. As the car transitions weight from one side to the other, independently suspended wheels would maintain the ride angle of the wheels to the road which then maximizes the available traction of the tires. This is no advantange in a straight line drag race on a flat surface, but add a few bends and the car will corner much better. Also, in passenger cars built for comfort, an independent suspension would isolate bumps to one wheel, whereas a solid axle would transmit that bump to the other wheel also.

This is of course speaking in generalities. There have been hybrid designs of suspension that would address some of the differences also. Such as the deDion axle, or so called "semi-independent" suspensions common found on VW's Golf, Nissan's Sentra etc.

Our Fieros have independent suspension, but those from 84 to 87 were compromised in that they came from different cars of different weight classes. So they were a bit unbalanced. The front came from the front of the chevette and the backs were actually the front suspension from the Citation and later adapted from the GM-10 platforms. Probably a good idea, but not particularly well executed by GM.

quote Originally posted by Tinton: Also, in Fieros, independent suspension is never mentioned. Ever.

Actually, back when the Fiero was still in production, Pontiac mentioned the independent suspension quite a bit.

quote Originally posted by Tinton: Yeah, it has a torque arm in the rear and a "short/long arm (SLA)" front. What does that mean? Is that double wishbone?

The 3rd and 4th gen Camaros switched from a leaf spring rear suspension to coil springs. Leaf springs are mounted to the body of the car and the rear axle is held by u-bolts to the leaf springs. The leaf springs hold the axle in place so not much more is required for axle control. With a coil spring rear suspension, you need to have a way to control the axle from front / rear, and left / right, and you need a way to control the rear axles tendency to want to spin under acceleration. Lower control arms hold the axle front / rear, a track bar holds the axle left / right, and the torque arm stops the rear axle from spinning. I am not sure why GM went from leaf spring (which is generally cheaper to build) to coil in the rear of the later Camaros, maybe for ride quality (although my 3rd gen Z28 is a rough rider).

All Camaros had the Short / Long control arm (also known as double wishbone) setup in the front EXCEPT the 3rd gens, which had a strut suspension (which eliminates the upper control arm). The best way to learn about suspensions is to look in a few shop manuals instead of reading my rambling.....

Tim

[This message has been edited by FrugalFiero (edited 06-27-2006).]

quote Originally posted by beken: There have been hybrid designs of suspension that would address some of the differences also. Such as the deDion axle, or so called "semi-independent" suspensions common found on VW's Golf, Nissan's Sentra etc.

older rangers and broncos had Twin I-beam front ends, they had the strength and rigidity of a solid axle with the stability and handling of Independent suspension. only real drawback is it was damn heavy...