With all due respect to arijaycomet and lolachampcar, I wouldn't personally recommend lowering your Tesla this way to save a couple hundred bucks. I am a true DIYer and enjoy saving money where I can. With that being said, lowering a 100k investment without proper attention to maintaining loaded ride height seems highly likely it'd harshen the ride quality over an extended period of time.
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Group Buy - Eibach lowering springs for Model S
- Thread starter Popsmuf
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- Driving Dynamics Model S
lolachampcar
Well-Known Member
Ok, now I'm confused.
Lowering by moving the spring perch down using the stock springs basically reduces useful load (the amount you can put in the car before it reaches Tesla's minimum design ride height). This is why it is not such a good idea to do it with stock springs and why "lowering" springs from "tuners" have increased spring rates (to help get back some of that useful load).
Lowering by using stiffer, shorter springs does stiffen the ride. It is the price to be paid for keeping some of the useful load. Note I said some. If you lower an inch on a 250 lb/in spring (about what Tesla uses if I remember correctly), you have to up the spring rate such that you get back that 1" of lowering times 250 lb/in or 250 lbs per corner of load capacity. It has been a long time since I looked at aftermarket springs for a street car but I seem to remember that the change in spring rate normally only got back about 25% of the LOSS in useful load. Fill the car to Tesla's maximum vehicle weight with stiffer/shorter springs and you will likely be well below the minimum ride height and may even be on the bump stops.
What confuses me is how operating the dampers at a lower point in their stroke is going to change the damper's valving and "harshen" the ride. I can assure you that did not happen on my P+. If you are saying that loading the car up and going beyond Tesla's designed lowest ride height is not acceptable, then I understand. At the extreme you will be riding on the bump stops which will really harshen up the ride. The exact same theory applies to both OEM and tuner springs; it is only the load point at which the problem occurs that is different.
My PD is the best of all worlds. Engineering stiffened up low speed bump and rebound to remove all that floaty feel that normally comes with air suspension. Slap some lowering links on it and you get the ride height you want while keeping all that load carrying capability (the car just adds more air to the springs). I'm a happy camper.
2015 P85D
Lowering by moving the spring perch down using the stock springs basically reduces useful load (the amount you can put in the car before it reaches Tesla's minimum design ride height). This is why it is not such a good idea to do it with stock springs and why "lowering" springs from "tuners" have increased spring rates (to help get back some of that useful load).
Lowering by using stiffer, shorter springs does stiffen the ride. It is the price to be paid for keeping some of the useful load. Note I said some. If you lower an inch on a 250 lb/in spring (about what Tesla uses if I remember correctly), you have to up the spring rate such that you get back that 1" of lowering times 250 lb/in or 250 lbs per corner of load capacity. It has been a long time since I looked at aftermarket springs for a street car but I seem to remember that the change in spring rate normally only got back about 25% of the LOSS in useful load. Fill the car to Tesla's maximum vehicle weight with stiffer/shorter springs and you will likely be well below the minimum ride height and may even be on the bump stops.
What confuses me is how operating the dampers at a lower point in their stroke is going to change the damper's valving and "harshen" the ride. I can assure you that did not happen on my P+. If you are saying that loading the car up and going beyond Tesla's designed lowest ride height is not acceptable, then I understand. At the extreme you will be riding on the bump stops which will really harshen up the ride. The exact same theory applies to both OEM and tuner springs; it is only the load point at which the problem occurs that is different.
My PD is the best of all worlds. Engineering stiffened up low speed bump and rebound to remove all that floaty feel that normally comes with air suspension. Slap some lowering links on it and you get the ride height you want while keeping all that load carrying capability (the car just adds more air to the springs). I'm a happy camper.
2015 P85D
Last edited:
For those who want to chime in on lowering height, we have a thread running here:
T Sportline Model S Lowering Springs
T Sportline Model S Lowering Springs
FlatSix911
Porsche 918 Hybrid
I am interested in learning more about lowering the ride height using the OEM springs ... any photos posted?
Lola, do you still have the adjustable perches and springs available for purchase? Thanks
lolachampcar
Well-Known Member
There was no interest so I tossed all the springs and threaded perches when there was no interest.
I found the best way to do my car was to use a competent machine shop to install several new external C-clip grooves in the existing damper bodies. This allowed me to settle in on the perch height and subsequent ride height that worked best for my needs.
There should be some pictures in the Lolachampcar performance modifications thread.
[lolachampcar] Performance Upgrade Efforts
I found the best way to do my car was to use a competent machine shop to install several new external C-clip grooves in the existing damper bodies. This allowed me to settle in on the perch height and subsequent ride height that worked best for my needs.
There should be some pictures in the Lolachampcar performance modifications thread.
[lolachampcar] Performance Upgrade Efforts
But it really isn't "any competent" machine shop that will ring grove a damper. Shocks have a relatively big diameter, for many chucks, and their bottom mount can make getting a concentric bite at least a little more challenging. "Competent" machine shops may also prefer not touching this kind of thing, because it's small potatoes and not something they can make a business out of. This is what you might run into. Replicating the grooves, that are already there, works great once correctly done. Just beware of clearance issues between the front and back, and bottoming out a (over)loaded car.
FlatSix911
Porsche 918 Hybrid
Ouch... Any hope to breathe life into it again?
I've sent mail to H&R, and they replied maybe next year (2018)...
I've sent mail to H&R, and they replied maybe next year (2018)...
Aftermarket companies gauge demand. Unfortunately, when Tesla pulled the MS coil suspension option they took out of production the strut that would house a modified spring. There may be enough owners to "group" up, but I would guess it is less likely these will be offered.
lolachampcar
Well-Known Member
Saimaannorppa
Member
Forget brand coil makers and find a workshop which makes coils for heavy transport. Buses and trucks have various custom needs for springs, and there are small specialized shops serving them.
I needed a replacement of rear coils for my old A8, and I wanted them with same stiffness and ride height as Eibach prokit which were to be replaced, but with 100kg extra load capacity. Went to a custom transport shop, they said no problem, took out springs, copied features and installed new springs. They've been perfect for about 5 years. Cost was 400 euros with installation. I expect you can find them cheaper in US.
I needed a replacement of rear coils for my old A8, and I wanted them with same stiffness and ride height as Eibach prokit which were to be replaced, but with 100kg extra load capacity. Went to a custom transport shop, they said no problem, took out springs, copied features and installed new springs. They've been perfect for about 5 years. Cost was 400 euros with installation. I expect you can find them cheaper in US.
lolachampcar
Well-Known Member
The only caveat to the above is that Tesla's springs are a rising rate spring thus you are most likely going to have to have a small run of springs wound to your specification. Not expensive if done in something like 20 sets.
Saimaannorppa
Member
Of course they can lower rates if there are more orders for same specification, but my point is that the big brand manufacturers are not the best to respond to custom needs.
The price included 4 wheel alignment, which was done very well in my case. I don't think these brand houses (which outsource manufacturing anyway) have installation or wheel alignment services, at least without dealer involvement.
I would consider twice lowering beyond car's allowed camber setting. My Audi started to eat tires from inside tread as it usually goes.
The price included 4 wheel alignment, which was done very well in my case. I don't think these brand houses (which outsource manufacturing anyway) have installation or wheel alignment services, at least without dealer involvement.
I would consider twice lowering beyond car's allowed camber setting. My Audi started to eat tires from inside tread as it usually goes.
I am totally necroing this thread. Has anyone actually done this with a Model S?
Aggmeister2010
Active Member
I'm not sure the idea you copied is the best one. Typically when you lower a car you want an adjusted spring rate with the reduced suspension travel in mind. I think your safest bet to ensure the longevity of your expensive car would be to buy a coilover kit.
I would love to, that is ultimately the best option, but we don't seem to have any suppliers in Australia. The most reputable it seems like is Airtekk. There is a set advertised on ebay for very cheap but I am not brave/stupid enough to try them.
My interest in all this is making the car more efficient. We have great roads where I live. I am thinking more about the early data from lowered model 3 vehicles using less energy where it is probably worth a 1in drop. This would put a coil Model S roughly at the same ride height as an air Model S set on Low.
It would be great if we could figure out if another vehicle's shocks can be used in the Model S. Maybe Mercedes or similar. It looks like best combo is air suspension shocks for the increased dampening. The problem is even second hand in Australia the air suspension shocks are twice the price of coil shocks. To buy a full set of second hand air shocks is the same price as buying coilovers! They are not quite cheap enough yet for enthusiasts to begin experimenting more thoroughly, except for very brave/knowledgeable owners like lolachampcar.
Aggmeister2010
Active Member
If it helps, I’d be happy to forward a package to you from a US supplier.
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