Rear upper damper mounts

Griff500 · 05-16-2015, 10:01 AM

So, I've got a complete 1M setup going in at the rear along with Ohlins R&T.

My question is, what's the best rear damper top mount for mostly road use.

I've seen Dinan and powerflex make these but I'm currently thinking I'll just replace with OEM parts.

Comments/experiences welcomed

chris82 · 05-16-2015, 11:00 AM

Quote:

Originally Posted by Griff500

So, I've got a complete 1M setup going in at the rear along with Ohlins R&T.

My question is, what's the best rear damper top mount for mostly road use.

I've seen Dinan and powerflex make these but I'm currently thinking I'll just replace with OEM parts.

Comments/experiences welcomed

The OEM rubber upper mounts have a lot of deflection, even the 1M piece. The Dinan mount will solve this, and it also increases the travel of the damper by about 1cm

HP Autosport · 05-16-2015, 04:35 PM

Stock upper mounts.

Pig Farmer · 05-16-2015, 04:45 PM

Quote:

Originally Posted by Griff500

So, I've got a complete 1M setup going in at the rear along with Ohlins R&T.

My question is, what's the best rear damper top mount for mostly road use.

I've seen Dinan and powerflex make these but I'm currently thinking I'll just replace with OEM parts.

Comments/experiences welcomed

I installed the Dinan upper mounts with my TCKs. I've never had an issue with them and there is no additional NHV. There are two sizes (10mm and 14mm if I recall). If you go this route, just make sure you order the right size.

Dackelone · 05-16-2015, 05:03 PM

I would go with DINAN rear shock mounts. Everyone loves them. IF you go OE you might look at the Z8 rear shock mounts. I think it was Harold who first started to recmommend the Z8 mounts as a upgraded part.

Griff500 · 05-17-2015, 04:29 AM

Thanks all, I'll give the Dinan mounts a try then.

Not sure what size the 1M Ohlins dampers will be. I'll measure when they arrive unless anyone knows?

_Ryan_ · 05-17-2015, 08:03 AM

Quote:

Originally Posted by HP Autosport

Stock upper mounts.

OP- a vendor is telling you to use the standard part rather than buying something they can sell you... I'd listen to them. (plus, Harold hasn't steered us wrong, yet).

Griff500 · 05-17-2015, 04:00 PM

Quote:

Originally Posted by _Ryan_

OP- a vendor is telling you to use the standard part rather than buying something they can sell you... I'd listen to them. (plus, Harold hasn't steered us wrong, yet).

Thanks Ryan. Yeah, this is why I posted, there doesn't seem to be a clear solution here. Lots of people swearing by the DINAN mounts whilst others suggesting the OE part is the the best choice.

I don't want to introduce any more NVH through changing the mount, this is my main priority.

andrey_gta · 05-17-2015, 04:03 PM

Strong flex.eu makes cheap in 80 A and 90A

I bought some 80a recently 2 week delivery from poland

E82MSport · 05-17-2015, 08:27 PM

Quote:

Originally Posted by Griff500

So, I've got a complete 1M setup going in at the rear along with Ohlins R&T.

My question is, what's the best rear damper top mount for mostly road use.

I've seen Dinan and powerflex make these but I'm currently thinking I'll just replace with OEM parts.

Comments/experiences welcomed

I suggest OEM. I've had zero issues with mine and I also track my car.

Kgolf31 · 05-17-2015, 08:29 PM

Quote:

Originally Posted by HP Autosport

Stock upper mounts.

I just had a stock mount fail on me yesterday. One year of use with 700 pound springs

HP Autosport · 05-18-2015, 01:00 AM

Quote:

Originally Posted by Kgolf31

I just had a stock mount fail on me yesterday. One year of use with 700 pound springs

That is not exactly where the load is, but your mounts may have failed because of age or exposing to the elements.

High rate springs will typically cause the OE none M subframe bushings to fail prematurely.

John_01 · 05-18-2015, 02:32 AM

I've got Powerflex upper shock mounts. They were recently installed at the same time as the TC Kline rear dampers.
I can't compare with stock shock mounts, but at least the car handles well and is still very comfortable with the upgrade.

fe1rx · 05-18-2015, 04:51 PM

Quote:

Originally Posted by HP Autosport

That is not exactly where the load is, but your mounts may have failed because of age or exposing to the elements.

High rate springs will typically cause the OE none M subframe bushings to fail prematurely.

True that the spring loads don't go directly in to he shock mounts, but the shocks will be stiffer than OE when they are properly matched to stiffer springs. Hence stiffer springs do mean higher shock loads.

"Race Car Vehicle Dynamics" (pp 797-799) describes the function of "damper end rubbers" aka "relaxation springs". They permit a small range of motion before the damper has to move. The authors suggest that by permitting significant flexibility over small deflections (about 1/10 inch) they produce lower transmissibility at high-frequency small-amplitude inputs (above 20 Hz). Because they effectively go solid beyond that the damper is able to control larger amplitudes.

Taken to extremes a relaxation spring would result in loss of the ability of the damper to properly control wheel motions. As BMW uses them even on their M cars, the OE obviously considers them worthwhile with respect to NVH. I suspect that they are more useful when using runflat tires, which will tend to put more harshness into the suspension.

I have Powerflex upper shock mounts on RE-71Rs and don't have any complaint about higher frequency NVH from the rear. Even at higher tire pressures this tire is quiet over most surface irregularities, so that probably helps.

Based on dyno testing of my Ohlins R&T rear dampers, the damper loads range from +100 to -300 lbs at 10 in/sec. (at the damper, not at the wheel).

http://www.1addicts.com/forums/showp...&postcount=156

I tested the OE and Powerflex upper shock mounts, but only in the compression (+ve) direction. The upper mounts are actually softer in the rebound (-ve) direction.

http://www.1addicts.com/forums/showthread.php?t=1075240

OE mounts are about 2300 lb/in implying a deflection of 0.04" in compression and presumably something over 0.1" in rebound. The yellow Powerflex mounts have a stiffness of about 17000 lb/in, implying a deflection of 0.006" in compression and presumably something over 0.02" in rebound. Clearly the OE mounts function as relaxation springs and the Powerflex mounts don't.

HP Autosport · 05-19-2015, 12:16 AM

I still use the terminology "mounts" instead of "bump" and "rebound" cushions so not to confuse people any further. In some of my threads I have mentioned how shock mount(s) can affect damper reaction time and allow the dampers do what they are meant to do.

The OP has a street car the the OEM mounts will work just fine.

05-16-2015, 10:01 AM	#1
Griff500 Private 30 Rep 81 Posts Drives: 135i Join Date: Aug 2013 Location: Home iTrader: (0)	Rear upper damper mounts So, I've got a complete 1M setup going in at the rear along with Ohlins R&T. My question is, what's the best rear damper top mount for mostly road use. I've seen Dinan and powerflex make these but I'm currently thinking I'll just replace with OEM parts. Comments/experiences welcomed
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05-16-2015, 04:35 PM	#3
HP Autosport Supreme Allied Commander 3842 Rep 54,352 Posts Drives: F80 M3 Join Date: Mar 2007 Location: Santa Barbara, AP, Brembo, GIAC, Koni, Ohlins, Performance Friction, www.hpautosport.com iTrader: (36)	Stock upper mounts.
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05-16-2015, 05:03 PM	#5
Dackelone European Editor 10539 Rep 22,992 Posts Drives: N54 e82 Join Date: Feb 2010 Location: Bayern, Germany iTrader: (1)	I would go with DINAN rear shock mounts. Everyone loves them. IF you go OE you might look at the Z8 rear shock mounts. I think it was Harold who first started to recmommend the Z8 mounts as a upgraded part. __________________ Dackel's European Delivery Museum Guide
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05-17-2015, 04:29 AM	#6
Griff500 Private 30 Rep 81 Posts Drives: 135i Join Date: Aug 2013 Location: Home iTrader: (0)	Thanks all, I'll give the Dinan mounts a try then. Not sure what size the 1M Ohlins dampers will be. I'll measure when they arrive unless anyone knows?
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05-17-2015, 04:03 PM	#9
andrey_gta Brigadier General 298 Rep 4,040 Posts Drives: 130i coupé ;) Join Date: Nov 2011 Location: Bimmerpost iTrader: (1) Garage List 2008 BMW 128i [10.00]	Strong flex.eu makes cheap in 80 A and 90A I bought some 80a recently 2 week delivery from poland __________________ 128i Sport 6MT converted to Euro 130i spec, 3.73 diff, tuned by evolve ~220 whp 207 wtq(ft-lb) SAE In-progress: //M front arm, M3 rack, e36M lip Wishlist: Coils, n55 mnts, headers, LSD, e60 finn diff "The 1-series is the last car that BMW engineered before the Germans, as a car-making culture, fell out of love with driving." - R&T 2013 135is
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05-18-2015, 02:32 AM	#13
John_01 Colonel 232 Rep 2,643 Posts Drives: E90 325i, E82 135i Join Date: Mar 2009 Location: Sydney, Australia iTrader: (0)	I've got Powerflex upper shock mounts. They were recently installed at the same time as the TC Kline rear dampers. I can't compare with stock shock mounts, but at least the car handles well and is still very comfortable with the upgrade.
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05-19-2015, 12:16 AM	#15
HP Autosport Supreme Allied Commander 3842 Rep 54,352 Posts Drives: F80 M3 Join Date: Mar 2007 Location: Santa Barbara, AP, Brembo, GIAC, Koni, Ohlins, Performance Friction, www.hpautosport.com iTrader: (36)	I still use the terminology "mounts" instead of "bump" and "rebound" cushions so not to confuse people any further. In some of my threads I have mentioned how shock mount(s) can affect damper reaction time and allow the dampers do what they are meant to do. The OP has a street car the the OEM mounts will work just fine.
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