Factory air suspension too slow
#1
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Factory air suspension too slow
2007 LS460L. I'd like to lower the car just a bit to even out the tire gaps and improve the appearance.
I can do this easily, but there is a problem. Almost daily I go to a place where the driveway approach is a very steep climb from the street to the parking lot, with a sharp crest over from slope to flat. At this point, if I approach directly (90-degrees to the crest), I just barely make it without scraping (high center).
If I lower the car at all, that will be a problem.
My previous car (2002 MB S55), had the ABC hydraulic suspension, and the transition from normal to high (via a button on the dash) was about 5 seconds.
The LS takes at least 60 seconds, if not more - not an option. I don't want to have to remember to start raising the car a block or two from my destination.
Additionally, it would be nice to have a more reactive system when I have to parallel park against a high curb with passengers. On the MB, it was just a quick press of the button and I had less to worry about a passenger scraping the bottom of the door on the curb.
As I understand the system, the air pump is the only source of compressed air. When I press the "Height High" button, the compressor comes on and raises the car. The slowness is directly related to the available volume that can come from the compressor, which is obviously limited.
There are two ways around this issue, as I see it.
1) Separate reserve tank with separate compressor, holding about 150psi constant reserve. "T" this system in with a valve into the output of the existing compressor, probably with a check valve to control the direction of flow. Have the valve triggered (opened) when the compressor kicks on.
2) Replace factory compressor with a higher volume unit.
Of course, there will still be flow limits imposed by the individual valves at the struts themselves (assuming that's how Lexus has implemented the system). I would assume the factory lines are standard plastic lines that can probably take 200psi.
I'm not looking to create a car that responds like a low-rider, just one where I don't grow old waiting for the suspension to transition from normal to high ride height.
Suggestions are appreciated.
I can do this easily, but there is a problem. Almost daily I go to a place where the driveway approach is a very steep climb from the street to the parking lot, with a sharp crest over from slope to flat. At this point, if I approach directly (90-degrees to the crest), I just barely make it without scraping (high center).
If I lower the car at all, that will be a problem.
My previous car (2002 MB S55), had the ABC hydraulic suspension, and the transition from normal to high (via a button on the dash) was about 5 seconds.
The LS takes at least 60 seconds, if not more - not an option. I don't want to have to remember to start raising the car a block or two from my destination.
Additionally, it would be nice to have a more reactive system when I have to parallel park against a high curb with passengers. On the MB, it was just a quick press of the button and I had less to worry about a passenger scraping the bottom of the door on the curb.
As I understand the system, the air pump is the only source of compressed air. When I press the "Height High" button, the compressor comes on and raises the car. The slowness is directly related to the available volume that can come from the compressor, which is obviously limited.
There are two ways around this issue, as I see it.
1) Separate reserve tank with separate compressor, holding about 150psi constant reserve. "T" this system in with a valve into the output of the existing compressor, probably with a check valve to control the direction of flow. Have the valve triggered (opened) when the compressor kicks on.
2) Replace factory compressor with a higher volume unit.
Of course, there will still be flow limits imposed by the individual valves at the struts themselves (assuming that's how Lexus has implemented the system). I would assume the factory lines are standard plastic lines that can probably take 200psi.
I'm not looking to create a car that responds like a low-rider, just one where I don't grow old waiting for the suspension to transition from normal to high ride height.
Suggestions are appreciated.
#3
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Factory air suspension too slow
Your only choice is to install and aftermarket A/S system that will give you the speed you desire. The OEM A/S system is designed to be limited in its functionality, yes it is slow but I found it is a tad faster when the car is moving vs still.
#5
A lot of the other makes with aggressive air suspension are more prone for repairs.
If the system is modified to be faster then the way the system is designed it may lead to an early failure.
#6
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Reliabilty is #1 priority. That's why I got rid of my '02 MB AMG S55. Great car, but after nearly 200k miles, reliability was beginning to get dicey.
I'll do some more digging to see what the limiting factors are.
For example, It won't do any good to install a higher CFM compressor (assuming I do all diligence to properly power the unit without overloading the factory power circuits) if the flow through the valves is limited to what the factory unit can produce, or if the lines to the struts are so small that they restrict flow.
I'll do some more digging to see what the limiting factors are.
For example, It won't do any good to install a higher CFM compressor (assuming I do all diligence to properly power the unit without overloading the factory power circuits) if the flow through the valves is limited to what the factory unit can produce, or if the lines to the struts are so small that they restrict flow.
#7
Reliabilty is #1 priority. That's why I got rid of my '02 MB AMG S55. Great car, but after nearly 200k miles, reliability was beginning to get dicey.
I'll do some more digging to see what the limiting factors are.
For example, It won't do any good to install a higher CFM compressor (assuming I do all diligence to properly power the unit without overloading the factory power circuits) if the flow through the valves is limited to what the factory unit can produce, or if the lines to the struts are so small that they restrict flow.
I'll do some more digging to see what the limiting factors are.
For example, It won't do any good to install a higher CFM compressor (assuming I do all diligence to properly power the unit without overloading the factory power circuits) if the flow through the valves is limited to what the factory unit can produce, or if the lines to the struts are so small that they restrict flow.
At that point in time you are better off with an aftermarket system because at the very least you know what you are getting.
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#8
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It could well be that if I disconnect the factory compressor and use the factory harness to trigger a relay that activates a higher-capacity pump that the control module would store an error when it doesn't see the factory unit running...
What I wouldn't want to do is create a car that rides like it has been "bagged"...
#9
If the factory pumps has some kind interface that communicates feedback to a module then you could possibly leave them in line with an external compressor that just gets triggered by a relay. This would be a way to supplement the existing pumps.
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