What does grm think about air suspension

Pretty much as the topic asks, what do you guys think about aftermarket air suspension.

I've got a bunch of airbag stuff in my garage from when I was right into mini trucks. When I purchased the stuff ride quality and handling was never a consideration. But now I'm a little older and wiser the idea of bagging my truck still appeals, but only if I can do it in such a way that the thing rides nice and handles at least as well as it does now if not better. The main reason I'm considering air is that I can keep my low ride height but can also put a decent load in the tub without riding on bump stops

The vehicle In question is an 85 Mazda b2000, it's currently lowered with drop lca's and reset and reverse eyed leafs. It rides fairly well for a small truck on leafs and torsion bars, but I'd like it to be better.

Thoughts?

My only experience is with the factory air suspension on my Mercedes. I really like it. The ride is fantastic and if it's possible to recreate that using aftermarket parts, I'm all for it.
Anything that drops itself with a hiss when you park is awesome.

From what I understand, each bag needs it's own valve. That allows each bag to retain a constant pressure.

Other than that, I'd assume sway bars and shocks become much more important.

In reply to mazdeuce:

Factory air ride when working/maintained is awesome. If I can get even remotely close to that, I'll be stoked.

In reply to Dusterbd13:

That's definitely the most common way people tend to go about it. One inlet and one exhaust valve per bag. You can use a shared valve setup, but you need to use check valves to prevent air transferring from one bag to another as you corner etc.

Sway bars are on the menu weather I go with air or not. I'm wondering if adjustable shocks might be a good idea, I have no idea how you'd go about calculating the spring rate of an air bag or how that might change with load/ pressure increases.

What i think about air suspension is that i really wish it was cheaper for mcpherson struts.

In reply to Vigo:

As in air Mac Strut? Or do you mean it as you don't like air ride?

I approve of air suspension on cars. The ability to set the ride height on the fly means no more panicking about where you can and cannot go. And I love the people who say that air suspension is not for handling. Go ride in on of Air Ride Technologies' demo cars. They had a Chevelle that pulled 1.2g on street tires using their air coilover thingies and bolt-on suspension bits.

I've had air only suspensions on some bikes. It was unpleasant from a topping out perspective. That would be less of a problem with a car/truck, but not a non-problem either.

But it sounds like you're proposing air as a supplement to your truck. That could be dandy. Use enough air to bring the truck back up when loaded, bleed the air out when not needed.

My pickup truck fantasy suspension is one that lets me drop the truck to the ground for loading and unloading, then raise it back up when I got to drive it. Pickup trucks should not need ladders on their tailgates in order to get into the bed.

My Elky will ride on air someday.

I think most mini trucks go overkill on the bag sizing and that's why the ride is so harsh. They are using what amount to semi truck bags on a small pickup.

I think bag size is and issue, but so is uptravel. A lot of setups I see are riding at the very top of their travel range when low. If you only haven an inch of uptravel before you mechanically hit something then you either need to run extremely big bags for a very stiff spring rate, or you end up mechanically smashing things over any sizeable bump. If you want close to stock ride you need close to stock spring rate and close to stock uptravel.
Imagine a stock truck with 6 inches of uptravel, say 100lb springs (completely making up a number) so 600 lbs of force before you hit the bump stops. Now do a 4 inch drop so you only have 2 inches of uptravel and you need to triple your spring rate to 300lbs to not hit the bumps. It's not really linear of course because it's the shocks themselves that are actually absorbing the energy and turning it into heat, but it gives you things to think about. I'd concentrate on maintaining as much uptravel (and downtravel but I doubt that's a problem) as you can, finding a bag that is sized to give you a proper spring rate and be operating as close to linear as possible at that inflation pressure, and then getting shocks to work with it.
Good engineering, good guessing, and some trial and error.

daeman wrote: In reply to Vigo: As in air Mac Strut? Or do you mean it as you don't like air ride?

As in cheaper to get air springs to convert mcpherson strut vehicles.

A lot of setups I see are riding at the very top of their travel range when low. If you only haven an inch of uptravel before you mechanically hit something then you either need to run extremely big bags for a very stiff spring rate, or you end up mechanically smashing things over any sizeable bump

Well, most people only want bags so they can slam their car, and the problem with slamming your car is that even if you managed to still have compression travel in your suspension, you don't have it anywhere else, like from your wheels to your fenders or your oil pan to the ground. That's how i smashed the oil pan on my rebuilt engine the 2nd day after i got my old 5-spd caravan running. At some point the suspension is limited by everything else. I put different coilovers on it now that bottom out the bumpstops before anything else hits the ground. So i took away compression travel to protect the running gear. Low life!!

NickD wrote: And I love the people who say that air suspension is not for handling. Go ride in on of Air Ride Technologies' demo cars. They had a Chevelle that pulled 1.2g on street tires using their air coilover thingies and bolt-on suspension bits.

The fundamental problem with their systems is that lowering the suspension makes is softer and raising it makes it harder - the inverse of the relationship you'd want between ride height and stiffness for any kind of performance use. So with this system it doesn't make any sense to have an adjustable suspension for performance reasons instead of an old-school spring.

The only use their system makes sense for is if you want a suspension that is good both for hard cornering and hard parking. Low would be soft but if you want the lower ride height just for the sake of being low, that's OK.

I know i want to bag my corolla. Everything else i learned from my lowrider friends.

I would look to how the newer exotics are doing it with their nose raising shocks. I am not sure if they are air or mechanical, but the have conventional shocks with a fitting in the top of the mount that expands to raise.

Might be more work, but it seems to work for them.

My cousin put air suspension on his high-dollar vintage 911. Says that it works great, but I think that he just loves the look of it lowered down.

former520 wrote: I would look to how the newer exotics are doing it with their nose raising shocks. I am not sure if they are air or mechanical, but the have conventional shocks with a fitting in the top of the mount that expands to raise. Might be more work, but it seems to work for them.

Lots of these use a two stage system. At normal ride height the air portion is completely deflated and all of the suspending is done with springs. When it wants to be taller to get over speed bumps or something then the air part inflates. Who really cares how well your Lambo handles when you're going 7mph. Google air cups.
The idea behind performance air suspension is to make it work very very well at one ride height. That's performance height. Taller than that is for creeping out of driveways and lower than that is for hard parking, neither of which really care about dynamics.

mazdeuce wrote:

former520 wrote: I would look to how the newer exotics are doing it with their nose raising shocks. I am not sure if they are air or mechanical, but the have conventional shocks with a fitting in the top of the mount that expands to raise. Might be more work, but it seems to work for them.

Lots of these use a two stage system. At normal ride height the air portion is completely deflated and all of the suspending is done with springs. When it wants to be taller to get over speed bumps or something then the air part inflates. Who really cares how well your Lambo handles when you're going 7mph. Google air cups. The idea behind performance air suspension is to make it work very very well at one ride height. That's performance height. Taller than that is for creeping out of driveways and lower than that is for hard parking, neither of which really care about dynamics.

The one supercar that doesn't use this is the McLaren P1, it uses its ultra-complicated FRICS coilovers to adjust the ride height (independent of shock travel, like a variable lower mount) hydro-pneumatically. Sort of like having that old Citroen hydro-pneumatic suspension built into the shocks.

Air cups are fine for a "get over speedbumps" system but they're not meant to be driven around on when raised. The P1 runs at a higher ride height most of the time and lowers down to some ridiculously low ride height (2" IIRC) in "race mode."

It was extremely comfortable on my wife's old Lincoln Continental, until it ceased functioning. Then it was around $650 per corner to fix.

Love the OEM air suspension on my Jeep GC. Great for self-leveling when towing and used it for cranking up the height when running around Sliver Lake sand dunes. It helps the car stay flatter in the turns and drops down at speed for fuel mileage benefits. At times it feels a bit odd to me however. Count me as a fan.

I could do air cups. But what i REALLY want to do is just find some <$100 air shocks i can rig up as strut inserts to completely replace the stock damper on my cheap slammed mcstrut cars.

Not a fan. Yeah, load leveling is a nice feature as is ride height adjustment, but these systems always seem fragile ,compilicated, and huge money to repair. I'll live with standard springs, maybe adjustable coil overs.

In reply to NickD:

Pretty sure i read an article on one of their setups a while back. They seem to make a good case for aftermarket air in performance applications.

In reply to foxtrapper:

Air assist is a consideration, it certainly has an easy button element to it. That said, I already have most of the gear for a full air setup and it's probably not really suitable for an assist only role.

My truck will never be in danger of needing a ladder