Coilovers

[Oneel]

Hi guys just needed advice my 325 cab is sitting 60mm lower but the shocks have taken a pounding so was thinking of changing to coil overs. Can you recommend a brand or do you think I should just change the shocks?
Thanks in advance

[ross_jsy]

Don't bother. Ask yourself if you will be needing to change the ride height and dampening qualities of your car, unless it's a track car the answer is most likely no.

Buy decent springs and shocks. You can not go wrong with Bilstein shocks, I believe the B4's are popular with cabs.

[Oneel]

Thanks for reply my only issue with replacing just the shocks was how long they last and will they stop the car bottoming out. I was told with adjustable coil overs they last longer and the ride is a lot smoother. By the way I have decent springs which are fairly new but obviously with 2 dead front shocks they are useless

[Oneel]

Sorry should add got a guy with a complete spax setup he paid £650 for but never used and would supply and fit on my car for £450

[ross_jsy]

Bilsteins will more than likely out last your car. Cheap coil overs won't last a year and expensive ones are still need servicing and maintenance as they are for track use really, not scraping speed bumps.

If your suspension is bottoming out, it's too low. At 60mm it will handle like a pig anyway

[Grrrmachine]

A coilover IS a spring-and-shock; it's just built into one unit so that you can adjust its length of travel (and therefore ride height). If limit the travel by dropping to 60mm, then you're going to suffer a punishing ride - that's just how the laws of physics work.

To make your ride smoother, you need to raise the suspension back up so that it can do its job properly. Then fit Bilstein B4/6/8 shocks, depending on how stiff you want the ride to be.

[Oneel]

Ok I take that on board maybe bolstering is the way forward. Be honest I treat my 325 cab as a cruiser so as long as it's pointing in the right direction looking good Im ok with it. A lot of work was done before I bought it rolling the arches etc so it could take the 60 mm drop. Theirs no tyre scraping the body just the front shocks hitting the rubber stoppers.

[ross_jsy]

Sounds council.

The shocks are bottoming out as they have no more movement to give as they are already at the top of their stroke. Fit good quality suspension with a useable ride height and it will solve your problem

[Grrrmachine]

rolling the arches etc so it could take the 60 mm drop.

Width and height are two completely different things. Rolling the arches has nothing to suspension height.

Imagine it like this: you're dropping a priceless china vase onto the floor. Would you drop it onto a matress 4 inches thick, or 1 inch thick? Which one would protect the vase better?

Obviously it's the thicker mattress. Suspension travel is the same thing as the thickness of the mattress, so by cutting 60mm (2.5 inches) off it, you've significantly reduced its changes of protecting anything. That's why your shocks keep blowing.

[DanThe]

Spax is junk. Best springs for an E30 are Eibach and H&R

[Kos]

rolling the arches etc so it could take the 60 mm drop.

Width and height are two completely different things. Rolling the arches has nothing to suspension height.

Imagine it like this: you're dropping a priceless china vase onto the floor. Would you drop it onto a matress 4 inches thick, or 1 inch thick? Which one would protect the vase better?

Obviously it's the thicker mattress. Suspension travel is the same thing as the thickness of the mattress, so by cutting 60mm (2.5 inches) off it, you've significantly reduced its changes of protecting anything. That's why your shocks keep blowing.

Quite a generalised post

My e46 330i on H&R sport cup kit (55/35) with it's stiffer springs rides better and is smoother than my sisters 320d on M sport suspension. That's not only according to me but my my dad and his arthritic bones and bad back

Also, ghetto drops on e30's, even with standard size wheels and tyres will need an arch rolled

Motorsport cabs which sat quite low did have a different return lip to a normal e30's to avoid tyre scrub

[e30topless]

Ok I take that on board maybe bolstering is the way forward. Be honest I treat my 325 cab as a cruiser so as long as it's pointing in the right direction looking good Im ok with it. A lot of work was done before I bought it rolling the arches etc so it could take the 60 mm drop. Theirs no tyre scraping the body just the front shocks hitting the rubber stoppers.

I have lots of spare M20 sumps in stock

[pacerpete]

Itz a f000king lifestyle ! Sumpz /oil pumpz / level senderz here !

[bab-91]

[Grzesiek325i]

B4 imho are shit. Normal shock for stock springs. For aftwermarket sprigns without lowering B6 would be ok. For lowered car only B8. Also Koni regulated shocks are very nice

[Kos]

B4's are perfect for road use and with 35mm springs

[salam0506]

It seems as though all the aftermarket springs that are suggested (eibach and H&R) lower the car by 30mm+. Does that mean Bilstein B8 shocks have to be used? Is there a good combination that can be had for under £400? I't not fussed about lowering the car (I can live with or without) but would rather not spend £630 for the bilstein eibach kit.

[Kos]

H&R sport cup kit can be had for £400ish

60/40 drop

[salam0506]

How does this compare to the Bilstein kit? Does H&R make the dampers themselves or rebrand them?

[Kos]

How does this compare to the Bilstein kit? Does H&R make the dampers themselves or rebrand them?

Ive run cup kits on quite a few BMW's and £ for £ nothing beats them on a road car

The Bilstein kits to have the edge when it comes to out right handling however they can be too firm, this is the kits with the B8 Sport Dampers

The H&R shocks are made by Boge or Sachs to H&R specs

[salam0506]

Thanks Kos - with both kits being quite durable and long lasting it is hard to find an opinion from someone who has used both. I intend to use the car for mostly road use but later on the occasional track day would nice. Do you think pairing it with Eibach ARB would be a good idea or best to stick with H&R all round?

[salam0506]

Is there any difference between the touring and sport cup kit apart from the ride height? The H&R website states that " With a lower ride height and lower center of gravity, the handling of your vehicle will be improved over stock" but from what I have read on the zone it seems as though it is purely for looks?

[Kos]

Lower centre of gravity helps with handling plus the spring rates differ

As for ARB's it's up to you. Both are good

For a street it has to be H&R cup kit or the bilstein kit with B4 shocks, but H&R sport cup kit with its
60/40 drop gets my vote as it has the best stance to go with the handling

[miniblob]

I ran a 2.7 touring on an H&R cup kit briefly and it was lovely to drive on the road!!!
The previous owner who fitted it tracked it a lot and was happy with it. (I believe he had something to do with TVR race cars too!!!)
Though I've never, (knowingly), experienced a decent Bilstein setup!!!

I run my current 2.7 touring on H&R Coilovers, (daily!), and although it's not as harsh as people expect, it's obviously not as comfortable/flexible as the cup kit!!!
Handles extremely well and is adjustable, but will you ever bother???

I also run H&R anti roll bars, which are also adjustable, (no idea if other makes are adjustable!).

'Cos I'm a lazy git, I never bother adjusting anything though!!!

Bottom line, if I was doing it all again with the knowledge I have now, I'd be happily fitting the H&R cup kit!!! Probably!!!

Oh and I believe the only difference with the touring/cabby setup is it's slightly stronger at the rear, to account for the extra weight over the saloons!!! (If that's what you meant!!!)

Not sure if any of that helps you, but there it is!!!

[DanThe]

The H&R coilover kit uses Bilstein dampers
Anybody that says Bilstein are shit does not know what they are talking about

[Blitz]

I would suggest a softer setup. Stiff suspension on a convertible is horrible. A set of Bilstein (cheaper one) Sachs or Boge shocks with Eibach springs.

[Andyboy]

Ideally, shorter springs need shorter damper rods which is why BMW M Technic shocks (Bilstein or Boge) have them - compare an E36 saloon front strut with an M Technic one. Generally speaking, you're okay with standard shocks when dropping 30mm on the front. You need to be able to compress the spring when fitting - if the lowering spring can be fitted to the front strut without use of spring compressors, it's useless. The ride will be stupidly soft and it'll just bounce along on the bump stops.
Coil springs are rising rate - the more you compress a coil, the stiffer it gets. That's why coil springs are under so much tension even with the strut off the car. That static spring tension is the starting point from where the spring rates start. It's under tension with the wheel off the ground, under even more as the car is sat on its wheels, taking the weight of the car and from there, the spring does the real work when the car is driving along, cornering, hitting pot holes and so on.
I've just fitted an Eibach 30mm kit to an E36 and it works perfectly. The springs needed some serious compression to get them on yet it sits an inch or so lower and rides better than stock.

B4's are okay for road use when not lowered much but as was suggested above, they are really just a standard replacement and are not a performance upgrade. They're not shit, but I prefer the Boge Sachs version as fitted by BMW.

[Grzesiek325i]

If I look for stock damper i wont chose B4. Sachs Boge ok but i saw few damaged B4s after small mileage.

B6 and B8 it's a different damper and different technology

[miniblob]

The H&R coilover kit uses Bilstein dampers

Never knew that (obviously!!!)