lowered car too much? front suspension design?

[DaveJB]

So, I lowered my 07 Z4 M Coupe quite a bit. Unfortunately I lost the original ride height measurements but I think I'm at about an inch and a half. I used coilovers. I'm getting some seriously LOUD clunks/bangs when I go over sharp bumps in which something seems to bottom out. I can't see how it could be the coilovers so is there some control arm banging against some other part when this happens? I'm already resolved that I have to raise it but just want to confirm that this would actually help.

Thanks

[itdnwiwbp]

I'd say that's about where I am, maybe even a little lower up front. I've never had any unexpected sounds.

[3GFX]

Raising will definitely help but it's not necessarily the cure to your problems.

Being low can cause rubbing of the tire or rim onto the fender, or inner fenders. But this is more of a rubbing noise and will happen more on dips and bumps.

You can also have binding of the spring or collars that will cause a different clank. Or you could have loose items like the struts. Maybe your bushings are gone and its now just more noticeable. Tire size and rim can make all the difference on a lowered car as well. Your car does not look as low as some and it doesnt look like the tires poke out or are too wide.

Get under the car, check it out. Look everything over, get a buddy to ride with you. Take the tires off, look for rubbing on the fenders or inner wheel wells.

This is all standard territory for a lowered car.

Good luck.

[SDCoupe]

That looks sweet. What size rims and tires are you running?

[DaveJB]

It does rub in the right rear a bit, but that's not what I'm talking about. I'm talking a big LOUD BANG when I hit a sharp edged bump. It's likely that the strut is bottoming out in terms of travel. Not sure what hits though. Perhaps the top of the outside of the shock hitting the bottom of the radial bearing area.

Originally Posted by 3GFX

Raising will definitely help but it's not necessarily the cure to your problems.

Being low can cause rubbing of the tire or rim onto the fender, or inner fenders. But this is more of a rubbing noise and will happen more on dips and bumps.

You can also have binding of the spring or collars that will cause a different clank. Or you could have loose items like the struts. Maybe your bushings are gone and its now just more noticeable. Tire size and rim can make all the difference on a lowered car as well. Your car does not look as low as some and it doesnt look like the tires poke out or are too wide.

Get under the car, check it out. Look everything over, get a buddy to ride with you. Take the tires off, look for rubbing on the fenders or inner wheel wells.

This is all standard territory for a lowered car.

Good luck.

[DaveJB]

Originally Posted by SDCoupe

That looks sweet. What size rims and tires are you running?

Thanks!

Front Wheel Fitment
2 x APEX ARC-8 18x9.5" ET35 Wheel Hyper Silver $628.00 ARC81895ET35HS
Rear Wheel Fitment
2 x APEX ARC-8 18x10" ET25 Wheel Hyper Silver $648.00

I believe 275/35 18's in the back and 255/35 18's in the front.

[The HACK]

Which coil-over?

[DaveJB]

I'm a big fan of these guys after how responsive they've been to all my many questions, and the price and quality so I'd rather not say yet in case it's not on their end.

[RABAUKE]

Originally Posted by DaveJB

So, I lowered my 07 Z4 M Coupe quite a bit. Unfortunately I lost the original ride height measurements but I think I'm at about an inch and a half. I used coilovers. I'm getting some seriously LOUD clunks/bangs when I go over sharp bumps in which something seems to bottom out. I can't see how it could be the coilovers so is there some control arm banging against some other part when this happens? I'm already resolved that I have to raise it but just want to confirm that this would actually help.

Thanks

I know what this needs.....some woman with low self esteem and daddy issues wearing a bikini (no metal clasps to scratch) spread out on the hood. Oh oh, the booze is kicking in...

[RABAUKE]

Originally Posted by RABAUKE

I know what this needs.....some woman with low self esteem and daddy issues wearing a bikini (no metal clasps to scratch) spread out on the hood. Oh oh, the booze is kicking in...

I used to know this woman with no gag reflex.....nevermind.

[86Zed]

Originally Posted by DaveJB

Front 2 x APEX ARC-8 18x9.5" ET35
Rear 2 x APEX ARC-8 18x10" ET25

I believe 275/35 18's in the back and 255/35 18's in the front.

Running that wide of a wheel and tirewall in front is likely causing your car to rub for sure - otherwise the low stance is nothing new for these cars. How is your alignment?

[3GFX]

I'm not a tech, but a loud bang doesn't sound to good. Sometimes springs will turn within the perch and will make a loud bang, but only on cheaper coil overs (not that yours are, its just common with some brands).

You mentioned the manufacturer has been quite responsive. Have they offered any insight?

[AmmarYasirA]

Im not too saavy in these things, but I can agree with you that its got something to do with the suspension. Probably not bc of the wheel/tire fitment.

[inTgr8r]

Originally Posted by 86Zed

Running that wide of a wheel and tirewall in front is likely causing your car to rub for sure - otherwise the low stance is nothing new for these cars. How is your alignment?

Along this line.....
You likely have very little clearance wheel to strut.
If on something like KW3 with the shape of the spring you could be hitting it under compression

[EMKOOP]

Originally Posted by The HACK

Which coil-over?

Originally Posted by 86Zed

Running that wide of a wheel and tirewall in front is likely causing your car to rub for sure - otherwise the low stance is nothing new for these cars. How is your alignment?

Originally Posted by inTgr8r

Along this line.....
You likely have very little clearance wheel to strut.
If on something like KW3 with the shape of the spring you could be hitting it under compression

This.

It doesnt seem anything ridiculous from the photo but it would help if you also provide more info such as your current ride height front/rear (Measured from the fender to the wheel cap center OR from the fender to the bottom of the wheel)

[Jumbosock]

On my KWV3 I had to use 10mm spacers up front to not hit the strut. I also remember a story of somebody installing the rears on the wrong side (there is a left and a right) and it was making a huge bang when he hit a bump. He reversed the components and it went away.

[dre99gsx]

I am lowered on BC BR coilovers and get loud bangs on the rear only. From what I recall, this is usually caused by the pillow ball mounts on the shocks. I get the noise even if I raise it up 1". I'll point the finger on "cheap" coilovers.

example:

[DaveJB]

Oh my goodness, the last notification I got on this thread was 15 days ago. Ever since I joined here the notifications have been crap!

Anyway, I'll try to find some time soon to reply to you guys. Thanks for the suggestions.

[Vanne]

Are your fender inserts (plastic) rubbing through? If so you either need more camber or raise it a bit.