Author Topic: Bilstein HDs with M3 Springs (Read 4802 times)

max123 · « **on:** May 26, 2010, 12:01:11 AM »

Like the title says, will standard Bilstein HDs fit with M3 springs or should I use the Sports.

I currently have a set of stock 318is springs with HDs and am contemplating going to the M3 to drop the front a bit. I can't justify the loss if I have to replace the shocks as well.

Turner motorsport and Pelican parts both list the HDs as stock replacements for the M3 - but they also list the Sports as well so I'm guessing the M3 setup is right in between the two size wise. I just don't want to blow the shocks right away if i do the conversion.

tjts1 · « **Reply #1 on:** May 26, 2010, 12:05:24 AM »

Yes, they'll fit just fine. I had that setup for 2 years.

Stevie30 · « **Reply #2 on:** May 26, 2010, 12:18:54 AM »

I've been running HD's with M3 springs on my 325ic for about two years. No problems. The ride is great and the handling is good.

max123 · « **Reply #3 on:** June 03, 2010, 12:37:09 PM »

Just doing some digging on RealOEM, as I was thinking of upgrading to the M3 Springs.

As suspected, like most BMW parts, few items are exclusively manufactured for one model. The M3 springs (part# 31331130043) are better identified as part of one of the m-Tech suspension options, and according to RealOEM were offered as an option on the 318i with M10 motor and the 325e. Oddly, the M-tech springs listed for the 318is and the 325i are different.

Anyway, they may be more common than expected and may show up in unlikely places. They should be pretty easy to identify as they have a colored strip down the side and have 7 coils rather than 8.

Does anyone know the overall unsprung length so I can just take a tape measure?

max123 · « **Reply #4 on:** June 11, 2010, 10:27:03 AM »

Out of curiosity, has anyone ever compared the stock m-tech springs that were available as an option of the 318is compared to either the standard springs or M3 springs. I always assumed that the m-tech suspension was just pulled off the M3 but the part numbers don't match up.

Just curious if the m-techs are lower...

colin86325 · « **Reply #5 on:** June 11, 2010, 08:33:45 PM »

I wouldn't be surprised if the M-tech 318iS option was tailored to the lighter body weight of the 318iS (the M3 weighs more).

Jorgeconrico · « **Reply #6 on:** June 12, 2010, 07:30:17 AM »

Quote from: max123;93187

Anyway, they may be more common than expected and may show up in unlikely places. They should be pretty easy to identify as they have a colored strip down the side and have 7 coils rather than 8.

Does anyone know the overall unsprung length so I can just take a tape measure?

Hope this helps:

Rear

Front

max123 · « **Reply #7 on:** June 14, 2010, 11:33:47 AM »

Nice - 12 1/4" and 8"

Thanks for the photos - this should help alot.

Jorgeconrico · « **Reply #8 on:** June 14, 2010, 11:57:14 AM »

No problem amigo.