[Walker16]

BIMMERPOST / Classifieds

Asking Price:

USD 1,800.00

Location:

✓ Will Ship

Item Interest

Sold

So what I have is a used but never installed since being rebuilt/upgraded AST 4100/4150 coilover kit with Swift springs rated at 5kg front and 10kg rear

Pretty sure they are only for e90 & e92 but they may fit other models

Im asking $1800 Shipped within the US
If your in the SF bay area Ill give a price cut for picking them up!

I have everything need to install these including the ride height adjusting wrence its just not all in the picture because it is still boxed up..

Its kinda a long story how ended up with these but i was in what i thought was a minor curb hit which i found out yesterday evening that my car was going to be totaled and i never got a chance to install these...

PM/call or text any questions.. Andy 925-525-5039

So here is a quote from the guy I bought them from when he was selling them..

Hey Everyone,

I'm selling my AST 4100 Coilovers that have been completely rebuilt, re-valved, and upgraded to digressive pistons (technologically identical to the brand new AST 4150's). From their website: "New digressive piston design proven over two years in GRAND-AM road racing offering an increase in the low speed rebound adjustment range allowing for racecar damping on full stiff and a compliant street friendly damping on full soft"

Also included are a set a linear Swift Springs which are rated 5kg/Front and 10kg/Rear. These are perfect for spirited street driving and occasional tracking. My car stayed completely flat during cornering, while ride quality was smoother and more supple than stock.

I had this setup installed on my car for about 8 months and about 3,000 miles (without the digressive pistons) and I honestly could not have been happier. I had driven friends car's with KW V3's and Bilstein PSS10's, and the AST's were several notches above in both ride quality and handling. My car literally felt like a guided missile, able to change direction on a dime without all the drama of bumping and shaking. Also, I'm sure many of you have experienced that stock-suspension rear end skittishness during bumpy cornering...it's pretty disconcerting. Well, the AST's completely got rid of that fine feature The car stayed completely planted during cornering!

You might be wondering why I had these struts and shocks completely rebuilt and upgraded after only 3,000 miles. Well, unfortunately, the front left shock started leaking nitrogen and oil prematurely. This is what AST said to me in an email after I uninstalled and sent all 4 shocks to them: "This kit was a clearance set that had been on the shelf for some time. When a shock isn't used for an extended period of time, the seals can dry out and crack from not being lubricated by the oil, and that appears to be the issue with your set. We went through the each strut and shock and replaced every seal and o-ring and filled them with new oil."

AST handled this issue professionally and with a lot of grace. As you can imagine, I was pretty upset that a practically brand new shock failed considering I had never abused/tracked my car. As compensation for the hassle of having to lug the shocks from Hong Kong to the US as well as the installation costs, AST very kindly offered to do the digressive piston upgrade (US$1,000 value). I was excited about installing the rebuilt and upgraded shocks on my 335i, but I sold it before i had the chance Anyway, my loss is your gain!

[Raptor04]

Whats the inner diameter, length, and rate in pounds of the front swift springs?

[Walker16]

it is about 281 lbs front and 564 lbs rear

inner diameter of the front spring looks to be 2 3/8 inches and length is 8 inches