[DreamerJoe]

I'm searching for used springs and trying to widen my search a bit. since oem M3 springs fit the F30, it should be safe to say that aftermarket springs should fit also? seeing some used lowering springs on the F80 M3 board.. would the drop just be more or about the same as the spring lists for its application? I would also imagine the spring would be a bit stiffer than whats advertised because of the vehicle's weight difference..

[cfm56d7b]

How many miles does your vehicle have? Shocks usually reach the limit of their useful life before springs do.

If the shocks need to be replaced in the near future, coilovers (shocks + springs -> designed for your car) would be a good alternative.

[FaRKle!]

Originally Posted by DreamerJoe

I'm searching for used springs and trying to widen my search a bit. since oem M3 springs fit the F30, it should be safe to say that aftermarket springs should fit also? seeing some used lowering springs on the F80 M3 board.. would the drop just be more or about the same as the spring lists for its application? I would also imagine the spring would be a bit stiffer than whats advertised because of the vehicle's weight difference..

Yes aftermarket F8x springs should fit your vehicle, but they might not lower by the same amount they will for an F8x car (have to calculate weight and bump stop engagement differences). F8x OE springs might already lower your car, so lowering springs for that platform may lower even further.

As for the spring rates, there are a good amount of lowering springs for the F8x that are stiffer than the F8x base suspension, but less than competition pack suspension. You'll want to keep this in mind since you may be reducing your damping factor a good amount. This is typically why people think their stock dampers "went bad," because they've already reduced the damping by going to strong springs, and thus get closer to the point where things feel underdamped.

[DreamerJoe]

Originally Posted by cfm56d7b

How many miles does your vehicle have? Shocks usually reach the limit of their useful life before springs do.

If the shocks need to be replaced in the near future, coilovers (shocks + springs -> designed for your car) would be a good alternative.

car has just under 70k, and I will be replacing the shocks also. I was looking at coilovers, but for me springs make more sense. my last car I spent $2,600 on coilovers with an active controller, Tien comfort sport w/ EDFC, and honestly kinda of regretted it later and realized I would have been just as happy with something 1/3-1/2 the cost.

Originally Posted by FaRKle!

Yes aftermarket F8x springs should fit your vehicle, but they might not lower by the same amount they will for an F8x car (have to calculate weight and bump stop engagement differences). F8x OE springs might already lower your car, so lowering springs for that platform may lower even further.

As for the spring rates, there are a good amount of lowering springs for the F8x that are stiffer than the F8x base suspension, but less than competition pack suspension. You'll want to keep this in mind since you may be reducing your damping factor a good amount. This is typically why people think their stock dampers "went bad," because they've already reduced the damping by going to strong springs, and thus get closer to the point where things feel underdamped.

I will be getting some koni shocks (yellow) to pair up with the springs, I just wanted to open up some options because I'm looking for springs with a moderate drop like eibach or dinan and the seller to hopefully be local (wary of getting scammed), and not much meeting both of those requirements have crossed the F30 classifieds in the past few weeks, but someone selling springs local popped up on the F80 board so I just need to look into them a bit more.

[cfm56d7b]

DreamerJoe, thanks for the details.

I had the same car as yours in the past: 2013 F30 335i. After exhaustive research, I decided to install KW Street Comfort coilovers (about $1.6K). Was very satisfied with this product.