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View Full Version : Shockwave, or air bag questions in general



CFster
08-20-2011, 02:45 AM
I have an interest in airbags but have a few questions...

1. Ride height depends on stiffness and vice versa? So, if I want a stiffer spring rate, it would mean raising ride height? Softer would mean lower?

2. Can Shockwaves be made to work with the SPC lower control arms (the ones with the dropped spring pockets)? How about Varishock Shockwaves with factory style shock mounts?

3. How will stiffness be compared to SPC performance springs at a given ride height. How about vs. the stock springs?

4. In the rear, if I already have Varishocks, what's the drawback to running just an air spring and separate shock instead of a combined Shockwave spring/shock unit?

Thanks,
-Colin

1970 TT Rustang
08-20-2011, 08:04 PM
as far as your first question it can be ajusted with the damper and reboud if you get the shock with those options. Which i have.

JRouche
08-20-2011, 10:42 PM
I have an interest in airbags but have a few questions...

1. Ride height depends on stiffness and vice versa? So, if I want a stiffer spring rate, it would mean raising ride height? Softer would mean lower?

2. Can Shockwaves be made to work with the SPC lower control arms (the ones with the dropped spring pockets)? How about Varishock Shockwaves with factory style shock mounts?

3. How will stiffness be compared to SPC performance springs at a given ride height. How about vs. the stock springs?

4. In the rear, if I already have Varishocks, what's the drawback to running just an air spring and separate shock instead of a combined Shockwave spring/shock unit?

Thanks,
-Colin


Ok Ill chime in here but now way do I know about all the issues... Its ALL opinion.

Q 1... No ride height and a stiffness are not mutual. The spring to support the car at certain height is just that. It has nothing to do with the spring rate. You can support the same car with a similar "holding" pressure but once the spring is in motion the spring can vary alot for rate of compression and the amount of pressure. Springs are not linear with compression and rate. Springs (to a point) dont make a stiff ride, the shocks do.

Q 2.. Yeah, I dont see an issue. Might need to do some metal work. I have the SPC uppers and TCI lowers and had to do do some metal work. Are you asking if its a bolt in? If so I say NO.....

Q 3.. Thats unknown. And you wont find the answer. Not here anyway. I dont think someone has compared the diff springs for your car and the setup you have.

Q 4. Prolly packaging. Putting the shock in the center of the spring (like a coilover) helps with that. You dont have to try and fit separate mounts for the shocks and springs, all in one is nice. So that allows you to put the spring AND the shock out toward the wheel bearing flange. The closer to the wheel bearing flange ( or bearing housing) the better.

But WTF do I know? Nadda. Ive never worked on these darn cars. I say drive the wheels off the car THEN figure out what you need. JR

CFster
08-21-2011, 02:57 AM
Q 1... No ride height and a stiffness are not mutual. The spring to support the car at certain height is just that. It has nothing to do with the spring rate. You can support the same car with a similar "holding" pressure but once the spring is in motion the spring can vary alot for rate of compression and the amount of pressure. Springs are not linear with compression and rate. Springs (to a point) dont make a stiff ride, the shocks do.

I asked the question, so I'm no expert, but it seems this would be the case more so with a conventional spring than an air bag. A spring can be cut or manufactured to a specific length regardless of stiffness to achieve a desired ride height. An air bag is an air bag. You have to put air in it to achieve the desired height, and the by product is a different spring rate. Am I correct?


Q 2.. Yeah, I dont see an issue. Might need to do some metal work. I have the SPC uppers and TCI lowers and had to do do some metal work. Are you asking if its a bolt in? If so I say NO.....

Since yesterday I've discovered I have to cut the frame to make Shockwaves fit up front in my car. Not doing THAT...

marolf101x
08-21-2011, 01:23 PM
At ride height a traditional coil spring and an air spring are roughly the same. It takes a certain amount of spring rate to hold the car up at a desired height.
For example, let's say your car has a front end weight of 1800lbs, or 900lbs per corner, and your suspension motion ratio is 2:1, so the spring actually has to hold up 1800lbs per side. So you use a 600# steel spring and preload it 3 inches. The steel spring compressed one inch provides 600#. Compress it two inches, and you have 1200#. Compress three inches and you have 1800#, or enough to hold the car up at the desired ride height.
The air spring is the same kind of deal, only you add air pressure to attain the desired force to hold the car up. Let's look at a 6.5" double convoluted air spring (as that is what we use in the front) and you can see it takes 100lbs of air pressure to achieve 1800# force at the designed height of 5 inches.

Now is where it gets interesting. . .compress that steel coil one more inch (4" total) and you have 2400#. Compress the same air spring one inch, and your spring rate goes up to 2050# if the 100psi were maintained. However, compressing the air spring increases the air pressure, so you are no longer at 100psi, you could be at 115psi, which would provide a spring rate of around 2400#.

There is a very long equation you can use to compare the air spring to any spring you have, but as you can see, there are a lot of numbers involved to get what you want. This is not opinion, this is fact and is written in the Firestone design guide.

All the cars we have on air have the frame "clearanced" for the air spring. This is not as bad as it sounds. You are only removing the material in the spring pocket that GM rolled under inside the spring pocket. It's not much, just enough to provide clearance for the air spring. This does not effect the strength of the frame.

The Shockwave is available with a trunnion (T-bar) lower mount, so it will likely fit into the arm of your choice, but like has been stated you may have to do some additional work to make sure everything clears through full sous pension travel.

CFster
08-21-2011, 07:53 PM
Thanks for the explanation Britt, sending you a PM.

Hunter68
08-21-2011, 09:20 PM
i was wondering the same sort of question, and was kinda wondering how it all works such as the air srpings or shockwave springs, do you still need a shock with them? or do you not need a shock at all? and say at the lowest ride hight rides the same as a taller on and can it be made stiffer?

marolf101x
08-22-2011, 05:27 AM
An air spring is just that. . .a spring. You still need a shock.

From my personal experience driving both air spring and coil over cars side-by-side I feel the air spring cars are still better ride quality for normal everyday driving.
Take our first gen Camaros for example: I always thought Velocity was the closest thing to an M3 we've ever had. It was quite, ran smooth, and the ride quality was much more "plush" than an M3. Now, it wasn't "70's Caddy", Lazy-Boy smooth, but it was quite nice.
The 48 Hour Camaro, on the other hand has an excellent ride quality just a touch more on the stiff side (I was terribly surprised at the ride quality when I drove it to Nashville for the first outing!). It's stiff, but not so much that it rattles out your fillings. I would drive this thing anywhere at any time and have no reservations.

creekwood08
08-22-2011, 12:32 PM
Ive originally wanted to go to shockwaves this winter because my car is in need of a updated suspension but ive seen alot of guys switching to coilovers because ive read guys on here saying the air ride system can be kinda of "finicky". I dont like the idea of cutting my frame either but its really not alot of cutting more of just trimming so I dont feel quite as bad but alot of guys wanting to from shockwaves to coilovers. Are they switching to the triple adjustables to get more performance or they switching because they dont like the shockwaves? Is the air ride system a little to much just for a cruiser 69 camaro, or is the ride and adjustability (being able to have the slammed look parked and being able to ride the car a little higher over road obstacles) worth the extra time and money? just wanting everyones thoughts to maybe decide if i want to go air or coil.

Hunter68
08-22-2011, 03:39 PM
how are you supposed to fit a shock and the airbag in?

CFster
08-22-2011, 05:48 PM
how are you supposed to fit a shock and the airbag in?

It's all in one -->

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olblue51
08-22-2011, 06:14 PM
Call Marcus at SC&C and ask him about using the Shockwaves with SPC lowers. I had Shockwaves when I bought my SPC lowers from him. It was a couple of years ago but I think I remember him telling me about a plate they make that sits in the spring pocket of the LCAs that is specifically made for Shockwaves. I don't remember if it had anything to do with mounting since I think the trunion would bolt in fine without it but I do remember him saying it would help stiffen up the spring pocket.

Sorry I don't have any real world experience to help you any further but my control arms have been sitting new in the box since I bought them. That's been the story of my whole car for the last couple of years.

Hunter68
08-23-2011, 12:30 PM
thats what i thought they where for the camaros. i have never ridden in a air ride car so i do have some questions about them that i never was able to ask... so at any ride height it will be the same ride quality or can you adjust not only the height but how soft or firm it is?

chuckd71
08-23-2011, 09:45 PM
My understanding is that as you get higher you get firmer, which would make sense. It also means that as you lower the car you get looser so lower doesn't always equal better handling with bags. Depending on which shocks you get you can adjust compression and rebound. I have some double adjustables that I am hoping to get install once I pick up some lower strongarms.

jknight16
08-24-2011, 09:57 AM
The Ridetech air ride systems are really only meant to be driven at one very specific ride height. Yes, you 'can' drive it above or below ride height, but the system was not designed for that. If you want to make adjustments for ride quality, you will need to restrict yourself to adjustments of shock settings. To make this possible while on the fly, they came up with the electronically adjustable option for their shocks.

marolf101x
08-24-2011, 11:40 AM
It is not true to state "air ride systems are really only meant to be driven at one very specific ride height" Typically you can move the vehicle height an inch or so without dramatically affecting ride quality and/or handling. You are correct that if you go too far both will suffer. However, you do have room to play around. . .we do it ALL the time as not everyone who drives our cars likes what the last person had for a setting.