My F30 Suspension Upgrade
My F30 suffers from the common suspension problems of floatiness, bounciness, front-end dive during braking and crashing into dips on the road. On several occasions small bumps taken a little too aggressively will unsettle the rear end and gave way. The Missus complained about the ride almost everytime she rides in it. Rear passengers gets thrown about and several have complained of car sickness. It seems to be getting worse with time. Further to this, I fitted the MSports body kit with the MPerf add-on. This lowered the car body by 1" and added with the softness of the suspension, I crashed into road bumps resulting in the replacement of the front lower lip spoiler. Every time I climb the incline to park the car at home, the lip will scrape the road. After 2 years, I couldn't take it anymore and decided to do something about it.
I considered many solutions and setups from several brands. But I concluded that the chief culprit are the shock absorbers and decided on Bilsteins for its value for money and their reputation.
With the Bilsteins, I had the following options:
Option 1 - Change shocks only, keeping the stock springs and anti-roll bar.
Option 2 - Change shocks and springs, keep the ARB stock.
Option 3 - Change complete suspension which includes shocks, springs and ARB.
I considered the Bilstein B6 which are uprated shocks for non-lowered cars but availability was an issue.
I can have Bilstein B8 which is essentially the same shocks as the B6 but it can be used for both standard height and lowered cars. This is more widely available.
I was tempted to go for the Bilstein B12 set which consist of the B8 shock absorbers matched with shortened comfort biased Eibach springs. This setup will also allow me to fit beefier uprated ARB from H&R for better roll resistance. I didn't fancy the similarly shortened H&R springs because it is too sports biased. The B12 setup will lower the car by an additional 1" which would be totally unacceptable and will aggravate the lowness problem. I could upgrade the rims to larger 19" to compensate for this, but I am not ready to do this yet.
So I decided on option 1 - just replace the shock absorbers to B8 because it still gives me the option to go B12 at a later date. Installation of the B8 was very quick and painless. All it took was a couple of hours. It was an exact fit except that the standard bump stops had to be ditched cos they will not fit the larger B8 shafts. I immediately took the car for a realignment after the fitment.
The result of the B8 is immediately felt. It has transformed the car. The ride feels firmer and the road rumble is felt and heard more than previous. The bounciness, floatiness and dive are completely gone. The car feels more planted during cornering. I do feel the road surface undulations a bit more than the standard shocks. It is still comfortable, not jarring at all. I think the soft CSC5 tires are helping here. Dips or road humps can be taken more aggressively with a muted thud instead of the previous dive, crash, fly and loss of back-end. Now I can drive up the porch without scraping the lower lip.
It should settle down in the next few days.
My missus gives it the thumbs up when we took a dip on the highway at high speed. I am enjoying my ride again.
I strongly recommend it. Beware it will void your warranty.
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https://www.facebook.com/groups/THERJ/permalink/573353182805829/
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