Okay, cut the BS why coil overs?

[1968Maro]

Another stupid question authored by me, so let me start this way.

I have never driven a 1st Gen Camaro with coil over suspension, so I am hoping for real advice by people who have done the switch.

I am talking about the front suspension only

I am at the point on my car where if I am going to do a coil over conversion on the front frame, I need to do it now. But I am still unconvinced that this won't be a lot of time and effort that is ultimately not going to gain me that much more performance.

I am looking for ride quality, ride performance, and ride height in that order. I am not going to be entering into the autocross anytime soon, but I want the confidence to know I can chase down a modern car on the freeway if I wanted to.

It seems the number one thing that coilovers gain you is ride stiffness adjustability. Beyond that my understanding is that the gains in responsiveness are marginal (not night and day) over a traditional spring and shock suspension. (I am only referring to the front suspension, not the leafs!!!

However if you only want your car to ride one way IMO that seems like a tremendous amount of effort for not much gain.

I am speaking as the inexperienced here so please set me straight!

[parsonsj]

David,

Coilovers are just a way to package springs and shocks. That's all. By themselves they only allow one thing: adjustability.

Adjustability includes ride height, spring rate (assuming one uses the nice packaging afforded by coilovers to change springs), and bump and/or rebound shock behavior.

The adjustability of the shock depends on the type/brand of the shock. Some have single adjustability (both bump and rebound are adjusted with a single knob), and some have double adjustability (bump and rebound are adjusted separately).

One final comment: you said if you only want your car to ride one way IMO that seems like a tremendous amount of effort for not much gain. You'd need to clarify what a "tremendous amount of effort" means, but the nice thing about using a coilover package is that you can fuss with it until you get your car to ride the way you want. With a traditional/OEM shock and spring, you don't have the adjustability to do that. You're stuck with what somebody else thinks is the right way for your car to ride.

jp

[driftinblzr]

I don't have a F-body but I have a 2nd gen S-Series Blazer, with the stock V6, that I have QA1 ProCoil single adjustable system installed on. The front suspension is of the same basic design so that's why I'm commenting.

I ordered the kit with the higher rate 550lb/in springs ($450). I loved the ride but I couldn't get the drop I wanted. I found a set of NIB 350lb/in springs to install ($50). Plus I got the thrust bearing kit and spanner wrenches ($45).

I finally got the drop I wanted but now I feel as if the front end is undersprung. I do have the adjustability but I also dropped $545 total on a kit that lowered me 2" and I never adjust the damping on.

For the same money I could have went with some high spring rate circle track springs and ride height adjusters, plus some decent shocks and probably been cheaper and happier with the ride.

That's just my $0.02 I could be wrong.

Later, Doug

[wmhjr]

I've had this same discussion with Marcus a while back. I hate to sound like a broken record, but call him and you'll learn the pros and cons of coilovers, air, tubulars, etc. Suffice it to say that coilovers can provide adjustment in dampening, but not really ride height (after installed). At least not while maintaining good performance - at least that's what I took away. I'm not the expert and defer to those who are.

[Jim Nilsen]

It's like more work now or more work later. Once coilovers are in they are much less time consuming to change the ride and stance. Changing stock type springs and shocks is more time consuming. The cost is all variable on both.

I stayed with the transverse leaf on my C4 suspension because I had it and I wanted to have a baseline to start with. I would never know what kind of ride it would give me if I didn't use what I already had. I also will know that if I go to coilovers what that differnce is and then I will be able to go back if I don't like them.

It's all about the cost to me and that all depends what you are starting with. If you have no real parts to start with and a good budget I would think coilovers are the way to go.

Then there is AIRIDE SUSPENSION !!!!

[wmhjr]

So would one way to describe it be...

With coilovers, while building the car you can swap in different spring and shock combinations more easily to adjust both height and performance with more detail...

But once you're done, there is little if any mechanical advantage with them?

So, if you have a known combination that somebody can provide specific recommendations the advantage is debatable? But if you have a pretty "Non-standard" build, coilovers could really help out?

[John Wright]

Coil-over or traditional coil spring both work about the same as far as I'm concerned. Shocks for either style can be single or double adjustable, if you so choose. There is nothing wrong with either choice provided you match the shocks up accordingly.

For stock LCAs, I like the traditional coil spring/shock package.

IMHO, those little 5/16" factory shock bolts/clips were not designed to support the whole front end of the car...just provide enough strength to hold the shock in place as it works to control the suspension movements. Several tubular LCAs were designed with coil overs in mind so they beefed this area up.

[JRouche]

I dont know but I see alot of talk about ride height and coilovers and similar products (air springs). Not just here on this thread but everywhere.

Coilovers wont give you any ride height changes that wont ruin your suspension geometry. The same can be said for air springs or doing it the old fashioned way with cut springs.

You can only change the ride height two ways. Move the control arm mounting locations (new cross member) or a modified knuckle. And I say only two ways. There may be more. But for performance purposses a changing of the spring wont gain you performance. You will get the wanted ride hieght change. But in all cases you will screw up the handling. It may feel better, and look better. But the reality of it is you wreck the handling. That is if the car was set up correctly to begin with.

You will take the lower control arms and move them from a horizontal attitude to a pointing down attitude. So during compression of the suspension you will start out pushing the lower ball joint out. Then the big swap. As the lower control arm continues up the ball joint passes the three or nine O-clock position and starts to pull the spindle in.

The ol flip flop. And thats just looking at the lower control arm. Usually we dont focus on it so much because we engineer it to be level at ride height, to remove the flip flop.

Now... We have to look at the upper CA. Thats a whole diff animal because of all the various suspensions out there. Some of them can actually benefit from a change in attitude (angle). But if you dont know for sure then its just a crap shoot. Better to know where the short comings are for the uppers than just hope a spring change will help. And it usually doesnt. Poor upper arm geometry is usually so sever that a proper fix is needed.

So anyway. My thought on coilovers is they should not be used for ride height needs. Wrong drug for the disease. They are great for racing where a quick swap for spring pressures are needed. They work great for what they were designed for, which wasnt ride height changes. JR

[JRouche]

IMHO, those little 5/16" factory shock bolts/clips were not designed to support the whole front end of the car...just provide enough strength to hold the shock in place as it works to control the suspension movements.

Not to question but I think 5/16" steel is plenty strong. I dont think the factory even used anything that thick (its over a 1/4"). Maybe you meant the common 3/16" tabs? JR

[parsonsj]

Good point. While "ruin" is a strong word, the front suspension geometry has a finite sweet spot. Someone once wrote:

Ride height: the position of the body relative to the tires. A common way to improve a car's handling (and looks) is to lower the ride height. This achieves a lower center of gravity (always good) with stiffer springs (usually good). Lowering the car too much can cause problems since most suspensions are designed for 2 to 2.5 inches of bump travel. If you lower your car 1.5 inches, you may only have an inch of reasonable bump geometry left before undesirable side effects occur.

[Bryce]

I dont think its about adjusting ride height. I think its more setting ride height. Since spring length and rate are fixed elements its hard to dial in your suspension ride height to exactly what you designed it to be. So using a coilover or any adjustable spring mount will allow you to dial in the height, to some degree. I am talking about an 1" max.

[monteboy84]

But guys.... they look cool!!

In all seriousness, the guys who are going to benefit most from coilovers are the ones who like to drive to the track, then drive home. You can very easily swap coilover shocks and springs (if mounted outboard of the frame) to change rate, and can more easily access adjustments on the shock with having them mounted outside the frame. JRouche is right about ride height, you can't change it without screwing up geometry, so let's ignore that feature. They're easier to install/remove, and they're easier to change rate and shock characteristics. Beyond that, if your stock style arrangement is properly dialed, you shouldn't see a difference.


Not to question but I think 5/16" steel is plenty strong. I dont think the factory even used anything that thick (its over a 1/4"). Maybe you meant the common 3/16" tabs? JR

He was referring to applications where the stock lower shock bolts are used to mount coilovers. They're 5/16" diameter bolts, normally only used to attach the shock for damping.

[John Wright]

He was referring to applications where the stock lower shock bolts are used to mount coilovers. They're 5/16" diameter bolts, normally only used to attach the shock for damping.
What really grabs my attention aren't so much the 5/16" bolts, but those cheesy sheetmetal fender style clips that they use as a means of securing the bottom of the shock to the LCA....I can't imagine that is designed to carry the whole weight of the car...especially the "shock" load(pun intended) during compression of the suspension when hitting a large bump in the road.

[6spdcamaro]

I like coil-overs because of adjustability ( i know everyone else already said that). This year i went to the autocross in a 31 ford with qa1 coil-overs. Took a pretty good chunk of time off with simple adjustments, just turning the knob. On the way home the ride was extremely uncomfortable so at the next gas station we sat under the car, clicked the knobs back to where they were. The ride quality was a HUGE difference, and so was the handling. It was amazing how different it felt after adjusting the bump/ rebound. If you plan on tracking the car and driving to/from the track, i would definitely recommend doing the work now or you'll regret it.

[parsonsj]

I've done exactly the same thing:
1. Go to the track.
2. Forget to change the adjustment.
3. Make a run, feel lots of body roll.
4. Jump under the car, add to two or three to the current settings (QA1 single adjustable).
5. Make another run, feel less body roll, see time improvement.
6. Finish day, feeling good.
7. Drive home, hate the ride.
8. Put settings back where they were. Enjoy the ride.

jp

[Vegas69]

You don't need a coilover for adjustable shock settings. Coil overs are beautiful because they allow the perfect stance in a reasonable amount of time. Especially in a race enviroment when sometimes you need to go up instead of down.

[wmhjr]

I like coil-overs because of adjustability ( i know everyone else already said that). This year i went to the autocross in a 31 ford with qa1 coil-overs. Took a pretty good chunk of time off with simple adjustments, just turning the knob. On the way home the ride was extremely uncomfortable so at the next gas station we sat under the car, clicked the knobs back to where they were. The ride quality was a HUGE difference, and so was the handling. It was amazing how different it felt after adjusting the bump/ rebound. If you plan on tracking the car and driving to/from the track, i would definitely recommend doing the work now or you'll regret it.

Adjustable shocks will provide the exact same result in this case. No need for coilovers. I think that's what Vegas was also saying.

[monteboy84]

What really grabs my attention aren't so much the 5/16" bolts, but those cheesy sheetmetal fender style clips that they use as a means of securing the bottom of the shock to the LCA....I can't imagine that is designed to carry the whole weight of the car...especially the "shock" load(pun intended) during compression of the suspension when hitting a large bump in the road.

Absolutely agree, those clips are pathetic, does QA1 provide a replacement with the coilover conversions? My assumption by comments made here is that they do not.

I've not heard much good about those kits, it would seem to me that either a proper outboard coilover, or stock spring/shock arrangement would be superior.

[agent784]

Budget wise I've found that the Hotchkis TVS system works for me because it handles just like a modern performance car. For now it was the most cost effective way to make the car handle without breaking the bank.

As far as appearance, only us enthusiasts will notice the difference by looking at the car. Otherwise, most people could care less. Most people are more likely to like your car based on your choice of color before your suspension setup. Go with what you like. But if you have the money, I say go with the coils like DSE or Global West. Hell if you have money to burn, put in a corvette subframe and call it a day.

[wmhjr]

I'm honestly a little leary of ANY of the kits. I'd rather get something tailored for my specific build and needs. That's why I talked to SCC.

One of the reasons as an example: Look at Hotchkiss #CHESTR013 - which claims to be a steering upgrade for '64-7 GM A-bodies - including Buick, Old and Pontiac. Now I know that they at least differentiated the Pontiac from the Chevy. However, though I'm not sure I was under the impression that the Pontiac and Olds were the same, but not the Buick - or vice versa. It's been a while, but for some reason I've got it in my mind that the drag links were not identical on all 3 brands. I'm just not sure here, and the point is that "packages" are tricky things.

[John Wright]

Absolutely agree, those clips are pathetic, does QA1 provide a replacement with the coilover conversions? My assumption by comments made here is that they do not.

I've not heard much good about those kits, it would seem to me that either a proper outboard coilover, or stock spring/shock arrangement would be superior.
I would think that in many cases the opening needs to be widened to allow the larger shock body to enter through the LCA, otherwise you need to disassemble the LCA from the LBJ to get the shock installed....anyway, if you widen the opening you will most likely cut out the factory bolting location and then have to fab up some sort of new type of lower shock mounting point. I have seen guys plate this area of the LCA with 3/8" thick plate, then drill/tap new holes to mount the lower ends of the shock at the T-bar assembly.

Purchasing a set of tubular LCAs that are already set up for coil overs is an easy alternative.

[1968Maro]

Well yes,

But chaning the mounts on the LCA are not nearly as difficult as modifying the stock sub frame to accept coilovers, this is where I get my "all the extra effort" comment.

[driftinblzr]

I would think that in many cases the opening needs to be widened to allow the larger shock body to enter through the LCA, otherwise you need to disassemble the LCA from the LBJ to get the shock installed....anyway, if you widen the opening you will most likely cut out the factory bolting location and then have to fab up some sort of new type of lower shock mounting point. I have seen guys plate this area of the LCA with 3/8" thick plate, then drill/tap new holes to mount the lower ends of the shock at the T-bar assembly.

On the QA1 ProCoil system, you do ditch the clips. The lower "T-bar" or whatever it's called goes on top of the LCA unlike the OEM shock setup. Two 3/8", IIRC, bolts go do through the T-bar then the LCA. On the underside the bolts are held with nylon lock nuts.

I have a pic, but it's not all that great. Also please ignore the rusty endlink. I got new shorter length ones.

Later, Doug

[bret]

I've done exactly the same thing:
1. Go to the track.
2. Forget to change the adjustment.
3. Make a run, feel lots of body roll.
4. Jump under the car, add to two or three to the current settings (QA1 single adjustable).
5. Make another run, feel less body roll, see time improvement.
6. Finish day, feeling good.
7. Drive home, hate the ride.
8. Put settings back where they were. Enjoy the ride.

jp

This is EXACTLY what you can do with a ShockWave...EXCEPT omit step #4. You can adjust air pressure [and soon shock valving] from inside the car.
Definately enjoy the ride!

[Stu Seitz]

Coil overs also provide the ability to change the corner weights of your car.

[JRouche]

I see some guys talking about adjusting, but they are adjusting the shocks, NOT the springs.

Two legitimate uses of coilovers I see here (besides the coolness factor which is legit also) were from falcon and Stu.

Makes it easier to creep up on you preferred ride height. Yup Falcon.

And what Stu said, weight balancing. Its amazing to see how far off the side to side numbers are off. I have a set of digital scales. They are fun to play with. And you can jack the weights around with coilovers. But you still need to adjust the components of the car around to get a proper balance. Stiffening up one side to adjust for an imbalance will solve issues on a car that is really set up. As best as you can. But take it too far and the imbalance is gonna cause more problems. But I think Stu meant it for a car that is really set up and the driver is looking for the "sweet spot". Scales and coilovers can help you find the sweet spot. JR

[JRouche]

This is EXACTLY what you can do with a ShockWave...EXCEPT omit step #4. You can adjust air pressure [and soon shock valving] from inside the car.
Definately enjoy the ride!

Not so quick.. He was talking about adjusting the shock valving. Not the spring (I think). You will still have to crawl under the car to adjust the shock valving on the shockwaves. Unless you guys came out with a new product? :) JR

[terryr]

They could also allow you to move the lower mounting point out nearer the tire. This would make the motion ratio closer to 1 to 1. [with custom lower arms.]

Easier to change springs. Good for race cars.

Easier to package custom suspensions.

[Bryce]

Thanks JR,

RideTech did come out with a new cockpit adjustable shock valving. Kinda like what certain OEM cars have.

One more idea. Coilovers can easily allow multiple mounting locations. So the ride height can be changed dramatically without bottoming out the shock but the suspension geometry will suffer. This would mainly be for a rear suspension setup when changing from roadcourse to drag. You can raise the car by changing the lower C/O mounting position.

[wmhjr]

Thanks JR,

RideTech did come out with a new cockpit adjustable shock valving. Kinda like what certain OEM cars have.


Related question. Has anyone ever had one of those OEM cars that had adjustable suspension that they really liked from a performance perspective? Not talking about "load level" type stuff - but actual performance. I wish i could say I have, but I've never liked the ones I've driven.

[Bryce]

from what I know, it adjusts compression and rebound at the same time. So a stiff shock verse a lighter shock.

[exwestracer]

They could also allow you to move the lower mounting point out nearer the tire. This would make the motion ratio closer to 1 to 1. [with custom lower arms.]

Easier to change springs. Good for race cars.

Easier to package custom suspensions.

Yes. Even though there is a lot of work involved in moving that lower mount out (including cutting the stock spring bucket out and moving the upper mount), it allows you to run much lower spring rates and remove a lot of the load from the control arm. Look at the lower control arms available from AFCO, etc. and you will see that they are MUCH lighter due to the force being transferred to the spring way out by the ball joint. Springs get lighter (3" vs. 5") as well. Not much gain in comfort, but a big step in reducing unsprung weight which gets more and more important as you go to low profile tires...

[JRouche]

Yes. Springs get lighter (3" vs. 5") as well. Not much gain in comfort, but a big step in reducing unsprung weight which gets more and more important as you go to low profile tires...

Unsprung weight and suspension springs..

Always something to look at. We used to have heavy leaf springs up front, prolly the worst for weight to spring value. Then we got coil springs. Much better. Then a car company used strait spring bars for suspending the car. Torsion bars, even better unsprung weight issues. OH, how bout a rubber spring. Thats pretty light. Air springs. They have to be the lightest. But Id love to learn about a cantilever suspension.

But for a simple reduction in unsprung weight Im thinking air springs are the simplest. And not without some performance. Talk about reducing unsprung weight, rubber air springs are the king. JR

[Chevy]

I see some guys talking about adjusting, but they are adjusting the shocks, NOT the springs.

Two legitimate uses of coilovers I see here (besides the coolness factor which is legit also) were from falcon and Stu.

Makes it easier to creep up on you preferred ride height. Yup Falcon.

And what Stu said, weight balancing. Its amazing to see how far off the side to side numbers are off. I have a set of digital scales. They are fun to play with. And you can jack the weights around with coilovers. But you still need to adjust the components of the car around to get a proper balance. Stiffening up one side to adjust for an imbalance will solve issues on a car that is really set up. As best as you can. But take it too far and the imbalance is gonna cause more problems. But I think Stu meant it for a car that is really set up and the driver is looking for the "sweet spot". Scales and coilovers can help you find the sweet spot. JR

Agree completely with JR and of course the two originally posters, Falcon and Stu. These two elements are CRITICAL to properly setting up the car for dynamic handling situations like the autocross or being able to set the old car up so it can run with (and even beat) a modern sports car in the twisties. As JR originally pointed out, nearly all short/long A-arm suspensions are designed so that the LCA is parrellel to the ground at ride height. To ensure that the car can be set up so that the LCAs are parrellel to the ground at ride height, you need coilovers--especially if the car has other mods and/or is a work in progress. When you relocate your battery to the trunk, do you want to have to buy a new set of springs? When you do a motor swap, ditto? How about when you buy a new set of tires with a little different aspect ratio? Coilovers solves all these issues with a few simple turns of the the wrench. The alternative is a whole collection of different rate/length springs and the time to swap them in and out, which gets expensive and tedious.

The other issue, that of weight jacking in the chassis, is also super-critical for dynamic situations and another element tha can't be accomplished without either coilovers or a vast collection of springs to swap in and out. It also changes anytime you move any weigh around in the car. With coilovers, that is not a problem...just a few turns away from being back where you need it.

These two elements make the difference between a well-sorted out classic Pro-Touring car that can run with modern Corvettes on the track and and an old car that someone has bolted some modern parts on.

[70camaro406]

Is adjusting the shocks (variable control) easier on a coil-over shock since it's easier to access over a traditional coil spring with the variable shock inside? I mean, since you can get variable shocks for both types of springs, is it just as easy to adjust the shocks on both types? Or is the coil-over shock easier to adjust? I know that I want the double adjustable shocks for my 2nd gen Camaro, just unsure about the spring, like the original poster.

[Bryce]

when the shock is inside the spring its hard to reach the adjuster knobs. where a coilover has easy access to the knobs.

[70camaro406]

I figured it would be harder. But is it still possible to reach them?

[LSx_88_Ciera]

Not really related to coil-overs but here is a good visualization of the effects ride height has on suspension geometry and ride height seemed to be a frequent topic in here.
http://www.racingaspirations.com/?p=286
I am working on a version based on the one above that allows you to enter the specs instead of the dragging points around.

[Roadbuster]

I figured it would be harder. But is it still possible to reach them?

Some adjuster knobs have a allen head in the center and the shocks come with a hex driver to get to the adjuster through the springs. Doesn't always work, and you might have to lift the car to make the adjustments, but better than disassembly.

A point in general with any type of shock is that there is a design sweet spot. The size of this sweet spot is proportional to the length of the shock. For our cars it is not much about +/- 0.5 inches. For a front suspension that is about +/- 1 inch of ride height adjustment. Running the shock out side this parameter will still allow it to work but will compromise performance on either compression or rebound.

For example: Varishock VAS 11111-350 coil overs have 3.50 inches of travel, which translates to 7 inches of wheel travel. The Compressed Length is 9.30 inches, Extended Length is 12.80, Minimum Ride Height of 10.70 inches, Maximum Ride Height of 11.40 inches. The minimum Ride Height is defined as 40% of travel available for compression (bump), 60% of travel available for extension (rebound). The maximum Ride Height: 60% of travel available for compression (bump), 40% of travel available for extension (rebound). All this is from the instruction sheet (http://www.varishock.com/Attachments/Instructions/899-031-200.pdf).

So for these coil overs 11.40 - 10.70 = 0.7 inches which translates to 1.4 inches of adjustable ride height. That is why shims or multiple mounting holes are required to adjust the ride height without pushing the shock outside its spec range.

Note that this range is for the shock. If you use a coil over, air spring or conventional spring you still want to set up the shock to be in its optimum range for the best performace.

Jon

[70camaro406]

Thanks for all the great info, Jon.

[monteboy84]

Still a good topic here, I've had some different experiences pertaining to this since the thread was first posted. Mainly circle track, but still relevant.

One thing we're almost always fighting with suspension geometry is the fact that most everything moves about a radius, which creates issues like bumpsteer, ackerman, camber gain/loss, etc.

With a conventionally mounted spring, one end is moving on a radius, which arcs the spring as the suspension moves through its travel. This introduces unknowns into the equation, such as rate change, and geometry-induced deflection which will change with every different spring. With a coilover, we're eliminating that and making all spring travel linear.

Also, coilovers allow the spring to act on a point much closer to the wheel centerline, which brings the wheel rate much closer to the actual spring rate. This also reduces the amount of flex in the lower control arm, which acts as a Class 2 Lever in a conventionally sprung suspension.

Now, all of this is getting fairly intricate in the gains it actually provides, and in most cases the average Pro-Tourer won't see much of a gain versus things like correcting the terrible factory geometry. But, if you're in pursuit of the "best of the best" it's certainly something worth looking into. For a racecar where they're allowed - it's a necessity if you want any chance at winning.

-matt

[overZealous1]

didn't read anything but the first post, so i'm sure it has been covered. harmonics of the spring.

thats about it. oh ya, ride height.

[HWYSTR]

Many are confusing ride height with weight jacking, but think that's been covered already, just as shock adjustment vs coil adjustment.

One thing I'd like to point out is that the rate of a spring that is smaller in diameter increases much more rapidly as it's compressed and is less granular than one that's larger in diameter. Height of a spring play a factor too. Total weight of what each spring is supporting is also a factor, like coil-over type suspensions generally are better suited for lighter cars, such as race cars. These reasons are why you don't see coilovers being used exclusively in production passenger cars (where it would certainly be a benefit on the assembly line).

That 'sweet spot' or range of motion the suspension travels in is where the spring also should be operating in it's range of compression where the rate is most linear. A spring at it's limit of compression (coil bind) or completely unloaded is not in it's 'sweet spot', if you can imagine.

.

[exwestracer]

Many are confusing ride height with weight jacking, but think that's been covered already, just as shock adjustment vs coil adjustment.

One thing I'd like to point out is that the rate of a spring that is smaller in diameter increases much more rapidly as it's compressed and is less granular than one that's larger in diameter. Height of a spring play a factor too. Total weight of what each spring is supporting is also a factor, like coil-over type suspensions generally are better suited for lighter cars, such as race cars. These reasons are why you don't see coilovers being used exclusively in production passenger cars (where it would certainly be a benefit on the assembly line).

That 'sweet spot' or range of motion the suspension travels in is where the spring also should be operating in it's range of compression where the rate is most linear. A spring at it's limit of compression (coil bind) or completely unloaded is not in it's 'sweet spot', if you can imagine.

.

If you change ride height by shortening or lengthening the installed height of a spring, you are jacking weight around...doesn't matter if its a coilover or big coil, tire pressure (it's an air spring), or a torsion bar. The only way to change ride height without jacking weight is to change the location of the spring in relation to the control arm or frame.

We test coil springs all the time (with a Longacre spring rater), and most linear springs show VERY little change in lb/in of rate, no matter where they are in their range of travel. That's exactly why we use them on race cars.... Most OEM springs are NOT linear; they are progressive to allow soft ride when lightly loaded, but not allow the car to bottom when heavily loaded or subjected to severe bumps. Progressive springs are easily identified by the varying distance between coils from one end of the spring to the other.

Many modern automobiles DO use a version of a coilover setup. It's just really big and looks like a Mc Pherson strut. If it has a single bolt and bushing at the bottom, it's just a coilover...

[HWYSTR]

If you change ride height by shortening or lengthening the installed height of a spring, you are jacking weight around...doesn't matter if its a coilover or big coil, tire pressure (it's an air spring), or a torsion bar. The only way to change ride height without jacking weight is to change the location of the spring in relation to the control arm or frame. ...

Exactly. But, as an example, you can use an adjustable spring cup at the frame side and remove the appropriate amount of coil(s) from the spring to achieve the original mounting position, and adjust from there.


We test coil springs all the time (with a Longacre spring rater), and most linear springs show VERY little change in lb/in of rate, no matter where they are in their range of travel. That's exactly why we use them on race cars.... ...

Coil over springs or traditional 5 - 5.5 springs? Some aftermarket springs have much better quality control than others, hence why many have problems with aftermarket springs, and why so many say to go to someone that can provide springs for your application. Most of the problem is with the quality control though. That problem can be with both, coil over and conventional 5 - 5.5 springs.


Most OEM springs are NOT linear; they are progressive to allow soft ride when lightly loaded, but not allow the car to bottom when heavily loaded or subjected to severe bumps. Progressive springs are easily identified by the varying distance between coils from one end of the spring to the other....

Yes, though cars from the musclecar era didn't come with variable rate springs. Hotchkis originally tried using variable rate springs in their' kits, but found they didn't work very well. (Boaty, or from weight it just compressed the 'variable' part of the spring at normal ride height).


Many modern automobiles DO use a version of a coilover setup. It's just really big and looks like a Mc Pherson strut. If it has a single bolt and bushing at the bottom, it's just a coilover...

And here is the point I'm trying to make about the diameter of the spring itself. The larger the diameter of the coils in a spring, the longer the lever arm, and the compression can occur much more granular, if I'm explaining that right.

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[79T/Aman]

"And here is the point I'm trying to make about the diameter of the spring itself. The larger the diameter of the coils in a spring, the longer the lever arm, and the compression can occur much more granular, if I'm explaining that right."

Larger springs react slower due to having to overcome their own weight but are a much more stable physical part when positiond half way between the inner pivot point and the ball joint, coil overs should be located as close to the ball joint as possible, doing so reduces the spring rate needed from the spring making the whole package lighter.

[exwestracer]

Exactly. But, as an example, you can use an adjustable spring cup at the frame side and remove the appropriate amount of coil(s) from the spring to achieve the original mounting position, and adjust from there.

That's not strictly a ride height change. It's a weight jack, and cutting coils off the spring will increase the spring rate, further compounding the issue...


Coil over springs or traditional 5 - 5.5 springs? Some aftermarket springs have much better quality control than others, hence why many have problems with aftermarket springs, and why so many say to go to someone that can provide springs for your application. Most of the problem is with the quality control though. That problem can be with both, coil over and conventional 5 - 5.5 springs.



Yes, though cars from the musclecar era didn't come with variable rate springs. Hotchkis originally tried using variable rate springs in their' kits, but found they didn't work very well. (Boaty, or from weight it just compressed the 'variable' part of the spring at normal ride height).

Well, ALL multi-leaf springs are progressive, as well as ALL pigtail coils (as found on the rear of most factory 4 link cars. Most front springs were linear rate. And you're right, progressive springs don't work all that well in handling applications.

And here is the point I'm trying to make about the diameter of the spring itself. The larger the diameter of the coils in a spring, the longer the lever arm, and the compression can occur much more granular, if I'm explaining that right.

One of the problems with a big spring, especially when used at 50% motion ratio, is the difference in compression between the outside of the spring and the inside as the A arm moves through it's arc. That's another advantage of a coilove with any diameter spring; the single mounting point eliminates any "accordion" effect.

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See above comments

[Ishmael]

Now that my brain is melted, and maybe this question was answered since its rediculously simple compared to everything else here but aren't qa1s designed to be a bolt on to stock lcas? If you want to accomplish ride height adjustment and have an adjustable shock they cost close to the same and you don't have to swap out springs so why wouldn't they be worth it for the money? Anybody posting that runs them on a camaro that can tell me if they are a bolt in?