MamadIS

I have BC coilovers with spring rates 12/10 installed on my IS350 and I was wondering what preload should I use given my spring rates? also not sure if important but i have 18x10 (offset 25) and 18x8.5 (offset 25) wheels with 245/40/18 in the rear and 225/40/18 in the front.

static250

I have the same setup and I run about 3 to 4 mm. I just used the spanner wrench to measure it. 3-4 mm is about the thickness of the wrench.

Kentchup

iTrader: (2)

yeah 4mm is perfect and is a ref

Gville350

iTrader: (10)

^I did the same! NO CLUNK NOISE TOO!

sm1ke

iTrader: (5)

Does anyone know if the coilovers already come preloaded? I got the BCRs but decided to go with the Swift spring upgrade, which meant I had to wait a few weeks before they could ship them out. I have them now and the springs are sitting in there pretty snug. Do I need to re-do the preload or do you guys think I'll be okay?

iRyan

iTrader: (7)

i believe you should be fine...

Gville350

iTrader: (10)

They do come close, but they're not pre-loaded right out of the box. I remembering having to give my spanners quite a few turns in order to get the correct pre-load per the video above.

sm1ke

iTrader: (5)

Well shoot, they're already installed. Oh well, no clunking noise whatsoever. If I ever have to adjust the ride height I'll set the preload properly. Thanks for letting me know!

SCWB

When I got my BC coils, the mechanic installed them straight out from the box. He was just ignorance or didn't know or care shXX about the preload. Later on, I had to adjust the ride height by myself, so I decided to check the preload of each coil. I found the spring preload-from the factory, of course, is different from one corner to another. So I decided to get the preload right for every corner. Caused me some time to get it right. It is not as easy to do the preload setting with coils installed onboard. If you have time, better check and set the preload "before" install your coils. It will be easier as you can see in the above video.

Boodoo

I checked out videos for the preload which I have never done with my previous coils on my vw's what is the main purpose of doing the preload and once I install them is there a particular way to adjust them to go lower and keep the preload at the same time?

ATP

iTrader: (1)

does any know what should be the rear preload on 3rd generation IS. oh yeah i have seperated springs and shocks on the rear.

VTsuckah

iTrader: (1)

Preload is per the brand/ model of the coilovers, not the car.