Coilover Spring rates Suggestions

So has anyone with BC's ever gotten stiffer springs? I know people with other applications have various springs available from BC, I wasn't sure if anyone with the FX had done so yet. I currently have the standard 8/12 and it's just not stiff enough. A big part of it is because my FX is low, but right now, I have to keep the damping set 2 clicks from full stiff or my tires rub everywhere. On the highway, it's not a big deal and the ride is controlled. But on surface streets and washboard roads, the ride is horrible. Also, I've noticed that while on small bumps, the ride is stiff because the damping is set so high, on actual big highway dips, the FX blows right through the travel. It feels undersprung.

I had nothing to compare it to before, but I recently picked up a 335i w/ KW V3 coilovers and that car rides like a dream compared to the FX. It's actually stiffer, but it feels much more planted and the spring rate and damping feel much more appropriately matched. So hopefully if I can get stiffer springs, I can turn the damping down a few clicks.
 
your comparing german made coils to taiwan coils. Ofcourse you will feel a huge difference. Friends 08 M3 sits on $2500 coils and feels so much better than this cheaply made taiwan coils that i have drove sti, g37, evo and etc.
I wish tein or kw made coils for our ride.
 
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Obviously there will be some difference in the damping between BC and KW. But I'm thinking the problem is more in the spring rate right now (and spring rates between expensive springs and cheap springs should be the same). It's just too low on the FX. I don't expect it will ever ride like the BMW (SUV vs. car), but I'm trying to get it to ride better than it does.

FWIW, most Tein coilovers are made in Taiwan.
 
I just got Kido coils with 10/12 springs and I wouldn't go any higher. My damping is set to 15/40 front and 27/40 rear and the ride is perfect. There's no way I could even think of bottoming them out. It feels like a more heavily damped (and an inch lower) H&R spring setup which is exactly what I wanted. I know Lance and Ed spec'd 12/12 for their FX45s as well.

Fwiw, I just bought BCs for my A4 avant, and the factory rates for that (much lighter) application are 10/12. 8/12 seems too low in the front for an FX imo...
 
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I was wondering about the spring rates on FX35 also. Thanks for the info Tim:good:
 
dont forget guys preload is really important, mine is at 0 preload and its not bad, i assume 5mm or more will roughen the ride up

---------- Post added at 03:26 PM ---------- Previous post was at 03:19 PM ----------
shadow191 said:
Obviously there will be some difference in the damping between BC and KW. But I'm thinking the problem is more in the spring rate right now (and spring rates between expensive springs and cheap springs should be the same). It's just too low on the FX. I don't expect it will ever ride like the BMW (SUV vs. car), but I'm trying to get it to ride better than it does.

FWIW, most Tein coilovers are made in Taiwan.
Click to expand...

ALL tein coils are manufactured and assembled in Japan
 
Dracula said:
dont forget guys preload is really important, mine is at 0 preload and its not bad, i assume 5mm or more will roughen the ride up...
Click to expand...

If your spring rate is the BC standard 8kg/mm front (10kg/mm rear), 5mm preload would be like adding 40kg (or 50kg) to the unloaded corner. Considering each corner of the FX weighs well over 300kg, the only realistic effect 5mm of preload will have is that you wont have to jack up the car as much (5mm less) to lift the wheel off the ground.
 
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Mine are preloaded at 5mm or so. If anything the preload should have helped since I feel the FX is undersprung. I'll keep researching to figure out options. I know BC makes stiffer springs for G's, so hopefully they'll have something.

With regards to Tein, I read everywhere that their Basics are made in Taiwan, then finished/boxed in Japan. Sort of like how high end Italian road bikes are actually made in China, then shipped to Italy for paint/finish work and a made in Italy sticker is slapped on. Not a big deal to me, I personally think Taiwan makes high quality parts.
 
You can get different springs for the BC's. I know my fronts rub a lot on any decent sized bump, but I have no issues with the ride, both twisty mountains and interstate for 700 miles.
 
I ran the BC's and believe they are quality products but after running the H&R's 1st the front spring rates at 8 never felt solid or as planted. It was easier (and less expensive) to order the KIDO's with the springs rates I wanted - 12/12. The ride difference was night and day over the OE BC settings of 8-10. Firm but not overly so, much closer to sport but still comfortable. At one point I had the BC's cranked way up on the firmness setting but it wasn't correct for the ride, the increased firmness did nothing for the overall roll, dive and dip factor.

TBH - I've only driven it one day since the KIDO C/O install (due to my ongoing build issues) but my techs who changed the C/O's out and who have driven it multiple times say it's a much better ride compared to the original set-up.
 
I can get you guys a BC springs with any rates. There is also a SWIFT upgrade option available for BC coilovers.

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Quick question guys. I just lowered my car and was able to do three sides. Front passengers side however the whole kit doesn't thread into the body so I am not able to lower it more. Any one else experienced this problem. Any help is appreciated. Thanks
 
Sounds like it just seized. Just spray some PB Blaster on it and let it soak over night. It might helps if you mount it to var to give you some leverage when you try to undo the rings or shock/ strut body
 
I sprayed pb blaster let it sit for a while but nothing. I tried spinning the rings down to lower the car nothing is happening. I hope it's not seized I put so much force into it that I kinda stripped the rings a bit.
 
So are the rings stuck or the body? My strut body has been sticky sometimes. What's worked for me is PB Blaster and then used the rings locked together as leverage. Make sure you've removed the preload before you try as well.
 
When I try to turn the springs in the front lock ring A the top one the whole spring won't move into the bottom body to lower the car. Lock ring C is loose but it just won't spin
 
Yeah, it sounds like what I've been through. It's annoying because there's nothing to use to turn the shock body to lower/raise the car and those threads get stuck pretty easily. But I'd try to use the lockrings that actually hold the spring and preload it. Tighten them together, then put the wrench on the top one to turn the shock body. It's always work for me in the past; hasn't damaged anything yet. Once you get past the initial tension, it should spin easier.
 
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