Who has stiffer springs on their BC Racing coilovers?
Why did you go stiffer?
What spring rate did you choose?
Front, rear, or both?
Did it help?
Ever since going the coilover route my car bottoms-out on the front very easily when going over speed bumps; it never did that with the airmatic, event though I have the ride height set about the same as the airmatic in lowered mode.
Also, the car feels a little "bouncy", even after making several adjustments to the preload.
Why did you go stiffer?
What spring rate did you choose?
Front, rear, or both?
Did it help?
Ever since going the coilover route my car bottoms-out on the front very easily when going over speed bumps; it never did that with the airmatic, event though I have the ride height set about the same as the airmatic in lowered mode.
Also, the car feels a little "bouncy", even after making several adjustments to the preload.
How much tighter did you go than 3-5mm on the preload?
I am dealing with the same upfront, I softened it up for DD mode to about 15-18 up front and it helped about 20% but still leaves me wanting more.
There was someone who jumped from BC 900lb spring to a BC 1000lb spring up front. I cannot wait for them to chime in
I have long tubes so speed humps are more like stop humps and slowly roll over them as gentle as possible. I am slightly lower than sport ii and it will still drag if I am not careful
I have not changed the front preload from whatever they came from the factory. I had to play around with the rear preload quite a bit, but I did see some improvement.
I talked with the guy at BC and he said I might want stiffer springs but I'd like to hear from someone first-hand who has done it.

I just looked at the KW site, same PN for either car. Makes sense the front would be undersprung
Last edited by E55wannabe; Jun 14, 2017 at 08:01 PM.
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BC and Megan come preset for our car and when you change that it's a ***** to get it back right
I just use the dampening
I never touched the preload setting it came with and rides perfect
So the real test will be in a couple weeks with the 1,000lb springs at Pocono track and hopefully no turn in suspension dive.
It has banked turns !!! ABSOLUTELY fantastic at speed although it will only be the shut down section after the 1/2 mile run. Still some cars will be over 200+mph so it's awesome to watch. !!!
I chose to get the standard rate in a swift spring and was pleasantly surprised with the improved control of my Lexus LS430 UL. Stoping distance improved, turn in is more consistent and relays good feedback, and rough roads aren't jarring. For the money, well balanced IMHO. I refrain from touching preload and focus on dialing in the valve response front vs back.
So the real test will be in a couple weeks with the 1,000lb springs at Pocono track and hopefully no turn in suspension dive.
It has banked turns !!! ABSOLUTELY fantastic at speed although it will only be the shut down section after the 1/2 mile run. Still some cars will be over 200+mph so it's awesome to watch. !!!

Dang summer's are busy times with an 11 year old not in school!
I hope to hear you got a good track test in!! A run at Pocono sure sounds fun to say the least. You are definitely going to be the most comfortable driver racing.
Trans is slowly coming along, about to finally run out and get a piece of PVC so I can use my press and push down the retaining spring to get the B1 piston out...
All parts in except f1 and f2 sprags (wanted to measure and make sure I got the right size) and snap rings to get appropriate clutch gap then back together she will go
The most challenging part is trying to stay organized enough through the time gaps when I have had to work on it...
Sorry for the thread jack Joe
I will prolly hit you up in a bit to make sure I am measuring these gaps correctly before I order the snap rings, it seems there are about 3 schools of thought on how to measure them
that's basically a synopsis of what i've discovered online over the years. it is recommended that it is ok to go stiff with swift springs as they'll ride better at a higher spring rate rating.
i would do mostly street daily driving but i dont want to order with the default settings and have the front bottom out when going over bumps like theyre saying...
Im debating between these 2 options
buying from vrpspeed with default spring rates(16k front and 15k rear) and adding swift springs
or buying directly from bcracing with 18k on the front and swift springs front and rear, and idk what spring rate on the rears🤷
Any opinion and experiences are appreciated...
Last edited by Thomas Alvarez; Jul 25, 2018 at 12:37 AM.









