SOLD AST 5100 Fast Road Coilovers for E85 E86 Z4M (mint)

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ed80

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 Bristol
These were removed from my Z4M before I sold it. They were fitted for approximately 6 months, and less than 2000 miles. Garaged and protected with ACF50 so zero corrosion.

Supplied by Balance Motorsport, they are a custom package that they developed for road use together with AST. They totally transform the car into a fast-road beast, and feel like a step-up in quality from KW V3s that I had previously on my E46.

I fitted brand new top mounts front and rear (BMW OEM at the front and Meyle HD at the rear) so they are ready to fit. The BMW top mounts are about £300 on their own. I will also include a set of Millway reinforcement plates for the rear shock mounting points, and a set of shorter front ARB links (from an E36 M3 so nice and strong). They will come assembled and pre-adjusted for stock ride height front and rear, but they have plenty of adjustment if you want to go lower.

Looking for £2000 £1800. With top mounts, reinforcing plates, etc they cost over £3000 new.
 
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typical ed, im just about to order nitrons. you couldnt upload some pictures or a spec sheet of spring rates. would be intereted in these, assuming you can get camber adjustable top mounts for these ?
 
Top mounts should be readily available, these are currently setup to use OEM top mounts so something OEM compatible should work, or you could ditch the OEM perch adapter and go with any top mount that is compatible with the (I believe) 60mm springs used.

The front springs are marked 200-50 and the rears are 220-40. As far as I know this means 50N/mm front and 40N/mm rear (and are 200 and 220mm long respectively).

I don't have any more details, but you can contact Julian at Balance Motorsport for more details, if you prefer then please DM me any questions and I can call him. Attached are a picture of the fronts. They still need a clean up, they are still coated in ACF-50.
 

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Busidhib said:
Hi ed80, are there any clearance issues with the ASTs clearing standard z4m alloys?
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Standard alloys clear, but only just. I could imagine there being issues if you run slightly wider tyres. I picked up some 3mm spacers (which I didn't end up using), just to give a bit more clearance. Happy to include these with the sale.
 
Bombardino said:
apart from the improvement in handling is there any improvement in comfort?
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I think the improvement in handling is day and night, but comfort is a more subjective thing, I will try to give an honest account of how they feel so hopefully you can make up your mind from there :)

Compared to the somewhat tired stock shocks and springs that the car had, these are definitely firmer, even at the softer end of their settings. However, they are also less crashy, and the ride feels much more controlled.

Hitting a pothole with these is controlled very progressively by the damper, the suspension doesn't travel far enough to hit the bump stops, so the feel of the bump is different. With stock suspension it often felt plusher on small defects, but it was easier to find the limits of the shocks and end up with a much crashier ride on rougher roads. These also feel faster to respond to small changes in road surface, the car feels lighter as a result (more like my current ride, an A110S actually).

Compared to my old E46 on KW v3 coilovers, these are definitely more comfortable. I don't have enough experience of E86s on other suspension to compare, but they are in a different league in terms of damping and quality to the likes of BC.

Sorry this was not very helpful, but it's difficult to convey this stuff in text.
 
My simple mind struggles to comprehend a stiffer ride at the same time being more comfortable on less than snooker table roads, I refreshed my suspension a few years ago with Bilstein shocks and OEM springs (initially had Eibachs on, they soon came off) however the ride is hard to tolerate on some roads.
What I really need is a drive in a car with coilovers to convince me its the way forward.
 
Bombardino said:
My simple mind struggles to comprehend a stiffer ride at the same time being more comfortable on less than snooker table roads, I refreshed my suspension a few years ago with Bilstein shocks and OEM springs (initially had Eibachs on, they soon came off) however the ride is hard to tolerate on some roads.
What I really need is a drive in a car with coilovers to convince me its the way forward.
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It's about the bump/compression (the rate at which the damper can compress after hitting a bump) and rebound (the rate at which the damper can return to full extension), and not just the spring weights or valving of the shock. Within this, there's also the type of bump/compression, as sometimes it's a sudden/huge bump, and othertimes it's just a milder hump.

The standard shocks (and the basic aftermarket ones) have zero adjustment, and are set to try and balance comfort & handling...and will always be a compromise as they can't be set up to work best in every condition...and even in something as simple as the swap from Z4MR to the stiffer Z4MC it feels much worse on the Z4MC.

Then there's also progressive spring, where they can be 'soft' for comfort for the first 30% of spring travel and then stiffen up.

Having something adjustable, especially when pushing on, can mean it puts the tyre back in contact with the road faster and gives you back control faster. Too stiff and it will skip, and this is where I think the standard suspension performs badly, as it's not compliant enough to soak them up, nor is it fast enough to react to small imperfections. My e34 M5 has very sloppy/comfortable EDC suspension, and if you saw it on road/track it leaned like a barge in a Force 10 gale...but that also mean the car was very comfortable to drive over rougher roads and all 4 tyres remained in contact with the road at all times to give you optimum control.
 
mmm-five said:
It's about the bump/compression (the rate at which the damper can compress after hitting a bump) and rebound (the rate at which the damper can return to full extension), and not just the spring weights or valving of the shock. Within this, there's also the type of bump/compression, as sometimes it's a sudden/huge bump, and othertimes it's just a milder hump.

The standard shocks (and the basic aftermarket ones) have zero adjustment, and are set to try and balance comfort & handling...and will always be a compromise as they can't be set up to work best in every condition...and even in something as simple as the swap from Z4MR to the stiffer Z4MC it feels much worse on the Z4MC.

Then there's also progressive spring, where they can be 'soft' for comfort for the first 30% of spring travel and then stiffen up.

Having something adjustable, especially when pushing on, can mean it puts the tyre back in contact with the road faster and gives you back control faster. Too stiff and it will skip, and this is where I think the standard suspension performs badly, as it's not compliant enough to soak them up, nor is it fast enough to react to small imperfections. My e34 M5 has very sloppy/comfortable EDC suspension, and if you saw it on road/track it leaned like a barge in a Force 10 gale...but that also mean the car was very comfortable to drive over rougher roads and all 4 tyres remained in contact with the road at all times to give you optimum control.
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Thanks for the explanation, this has given me a better understanding of how the performance differs to a standard set up, I think I still need a drive in a car with coilover to be truly convinced.
If it is indeed a night & day difference then these maybe worth a punt.
 
Cheeky offer here £1500 + postage cost to Newcastle upon tyne? No worries if not as its sorned for winter now anyway ☺️
 
If I didn't already have B16s on mine, this would be a very tempting offer - it still is, but I really don't need more spares filling up the attic.
 
These are sold STP, I will update the thread later if the sale falls through for any reason.
 
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