Inconsistant arch clearance... normal?

[OffdutyRockstar]

Quick question, my M has very inconsistant arch clearance front to back. At the risk of being vague the front allows a 3 finger gap and the rears just barely 2 fingers, is this normal?

Not the best picture to demonstrate but you can see the rather spacious front clearance...

Handling wise the car seems ok, there is a slight knocking from the rear that I can hear when the roof is up and the ride and damping as I have mentioned before seems extremely firm.

I have already bought a set of front bushes and have ordered some H&R Sport Springs and Rogue Engineering topmounts and was planning to get it all fitted in the next couple of weeks...

 

[Top pup]

The clearance sounds normal to me, most BMW's sit very similar.

Are you planning to fit new standard bushes on the front or uprated ones?

 

[AlanJ]

What's it like when you sit in it as your body weight is biased towards the rear axle? - you may find this levels it.

 

[Z4coupebeaver]

I wouldn't worry about the clearance but the knocking may be down to a broken rear spring. Not sure what you hope to fix with the new bushes - what's wrong with the originals?

 

[OffdutyRockstar]

I was advised that new bushes would help the damping and that the stock ones tend to go at around 40k, my car has 50k on the clock and being a relatively cost effective measure I am getting it done, I went for stock ones as apparently poly bushes make the damping even less compliant?

Good to hear that the arch clearance is normal however as stated, that knocking could well be a broken spring... what are the other symptoms of this?

 

[Top pup]

I went for stock ones as apparently poly bushes make the damping even less compliant?

That's why I asked, the uprated bushes add a fair bit of harshness to the suspension.

 

[Z4coupebeaver]

Broken rear springs are easy to identify. Just remove the rear wheels and take a look at the springs.

Re poly bushes - yes that is good advice. I believe you can get more compliant poly ones and they will last better than the cheese BMW uses for standard bushes but the ride does suffer and believe me - unless you are using it for track work - you don't want the ride to suffer.