E90Post
 


The Tire Rack
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > N57 / M57 Turbo Diesel Discussions - 335d > JRZ RS1 Dampers - Effect of Adjustments



Reply
 
Thread Tools Search this Thread
      04-29-2013, 07:51 AM   #1
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
JRZ RS1 Dampers - Effect of Adjustments

I guess this will be the final report on the JRZ RS1 dampers on my 2011 335d, unless sometime in the future I want to report on track results.

I have been riding at 12 of 24 all the way around with the JRZ RS1 settings. You can see how that was in my older post in the Suspension forum if interested.

So Saturday, with my wife in the car, I turned them all down to 6. Drove a little bit on city streets, including some brick, some usual crummy roads, but also US 50 and another smoother thoroughfare.

1. Still no wallowing at higher speeds. I got up to 80 or 85 and went over some bumps and depressions.
2. I took one of my favorite left-handers at a reasonably good clip, well, faster than everybody else. It is a bumpy turn with with some small holes that can upset your equilibrium in the turn. Anyway, I couldn't detect much in the way of increased body roll at all, and the usual bumps were not as noticeable.
3. OK, having said #1 and #2, let me say that it is smoother all around. There is less feel of every little nuance of the pavement surface, but not really in a bad way. I don't personally prefer it, but I know my wife did and your average passenger would also. I think I would set it down at 6 or so if I were driving interstates across country.
4. Doesn't seem to dive any more on hard braking, but honestly I didn't do much of that.
5. The turn-in didn't seem as crisp to me; the steering response is there, but there is not the instant response sense. Maybe it was psychological.

The next day I was alone in the car and I adjusted the dampers in the hard direction and all four corners are now set at 20.

1. Interestingly, I felt there was much less difference in going harder by 8 clicks than I had experienced above by going softer by 6 clicks.
2. It was noticeably firmer for sure, and part of that manifestation was in increase in the rattle I have in my dash already.
3. It wasn't objectionably worse over speed bumps or road imperfections. It just seemed to deal with them in a more "business-like" manner. Get it over with quickly and settle back down.
4. More stable on the highway at higher speeds, less body roll on the curves.
5. I'm guessing I would have to push it really hard, perhaps way beyond my skill level to really see the difference.
6. For me, I see no point in leaving them at 20, as the marginal improvement in handling for daily driving at least is not significant enough to need to endure the firmer ride. It was great at 12.
7. Another forum member who is interested in these dampers had said that another fellow had said his personal sweet spot was 13 in the front and 15 in the rear for daily driving, and as I remember 15 in the front and 17 in the back for the track. I'm sure the sweet spot is an individual thing based on driving habits and your local conditions, and it would certainly be true regarding track conditions also.

OK, that's all.
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.
Appreciate 0
      04-29-2013, 12:44 PM   #2
FormerRotor
Lieutenant Colonel
FormerRotor's Avatar
95
Rep
1,592
Posts

Drives: 2011 335d, M-Sport
Join Date: Jan 2012
Location: MD

iTrader: (5)

Garage List
DFan, every time you post, you remind me of my drive with you and make me want to spend money. Nicely written. I look forward to the eventual track comments!
__________________

My Picture Threads (Oldest to Newest): 1 2 3
Join BMW CCA! (Use my link and I get credit )
Appreciate 0
      04-29-2013, 04:17 PM   #3
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
Rotor, thanks. Well, today I drove 25 miles or so on various road types with front at 13 and rear at 15, and I thought it felt perfect. Will be interesting to see after tomorrow when I get on the ARC-8 wheels and Michelin PSS. Look out Sebastien Vettel. Hah!
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.
Appreciate 0
      05-21-2013, 07:59 PM   #4
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
Another comment on the settings for the RS1 dampers. Took a road trip from MD to Asheville NC, then to Pensacola, FL, then to Sumter, SC, and then back to MD. On long drives, whether on the interstate or state or county roads, the settings I was using for my daily driving here in MD (15r13f) proved to be a bit too harsh for all-day driving. I think when I do my next trip I will soften them up to somewhere between 6 and 10. And this is with Michelin PSS at about 38 psi all around.
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.
Appreciate 0
      05-21-2013, 08:06 PM   #5
GreekboyD
Brigadier General
Canada
411
Rep
3,049
Posts

Drives: 2009 BMW 335d
Join Date: Jan 2012
Location: Toronto, ON, Canada

iTrader: (0)

Garage List
2009 BMW 335d  [8.00]
Someone was telling me that the psi setting for the rears should be different than that of the fronts. Anyone know if this is true?
Appreciate 0
      05-21-2013, 08:34 PM   #6
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
Quote:
Originally Posted by GreekboyD
Someone was telling me that the psi setting for the rears should be different than that of the fronts. Anyone know if this is true?
The door panel on mine says 41 rear 33 front. For my HPDE the instructor suggested 36 all the way around to make it more neutral for the HPDE. It could be I should let some air out. I guess I could experiment a bit. I guess the door panel may assume RFTs, but don't know that for a fact.
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.
Appreciate 0
      06-01-2013, 01:54 PM   #7
cvc 22349a
Colonel
cvc 22349a's Avatar
United_States
164
Rep
2,556
Posts

Drives: 335i
Join Date: Sep 2007
Location: SF Bay

iTrader: (11)

Quote:
Originally Posted by 335dFan View Post
Rotor, thanks. Well, today I drove 25 miles or so on various road types with front at 13 and rear at 15, and I thought it felt perfect. Will be interesting to see after tomorrow when I get on the ARC-8 wheels and Michelin PSS. Look out Sebastien Vettel. Hah!
Interesting that you like the rear firmer than the front.. I know that to reduce pitch and balance handling with Koni's and KW's it's best to set the front firmer than the rear
__________________
2007 E90 335i, TiAg, 6AT, ZPP, ZSP, ZCW, 6FL, HD
Quaife lsd, ETS fmic, GIAC s/w, Dinan intake/exhaust/oc, Koni/M3 susp, Apex Arc 8, Mich PSS
Appreciate 0
      06-01-2013, 03:09 PM   #8
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
Quote:
Originally Posted by cvc 22349a
Quote:
Originally Posted by 335dFan View Post
Rotor, thanks. Well, today I drove 25 miles or so on various road types with front at 13 and rear at 15, and I thought it felt perfect. Will be interesting to see after tomorrow when I get on the ARC-8 wheels and Michelin PSS. Look out Sebastien Vettel. Hah!
Interesting that you like the rear firmer than the front.. I know that to reduce pitch and balance handling with Koni's and KW's it's best to set the front firmer than the rear
I guess that will be my next experiment.

One website gives this opinion about front and rear relationships with regard to damping:

Stiffer front damping (bump and rebound), increases grip at the rear of the car, increasing understeer characteristics.
Stiffer rear damping (bump and rebound), increases grip at the front of the car, increasing oversteer characteristics.

Damping Effect On Cornering:
Bump
Front Bump Increase= Understeer.
Front Bump Decrease= Oversteer.
Rear Bump Increase= Oversteer.
Rear Bump Decrease= Understeer.

Rebound
Front Rebound Increase= Understeer.
Front Rebound Decrease= Oversteer.
Rear Rebound Increase= Oversteer.
Rear Rebound Decrease= Understeer.

Other members may have different opinions or thoughts.
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.

Last edited by 335dFan; 06-02-2013 at 06:35 AM.. Reason: More detail on effect of settings
Appreciate 0
      06-03-2013, 07:18 AM   #9
335dFan
Jumping Jack Flash
335dFan's Avatar
United_States
321
Rep
1,692
Posts

Drives: 2021 X3 M40i
Join Date: Nov 2012
Location: California (east of Sacramento)

iTrader: (0)

Garage List
CVC 22349a, on the basis of your curiousity, and a subsequent suggestion by another forum member, I have adjusted my RS1 settings to 14f10r. Will report on results later. This AM it was raining and usual AM traffic.

BTW, since I got the RS1, all of my adjustments have been via a delta from where I was told they were at the outset (12f12r). So I suppose it would be wise for me to actually the baseline the settings by going full stop to one direction or the other, and then cranking in the exact offset.
__________________
2021 X3 M40i: M Sport Differential, Adaptive M Suspension.
Previous BMWs: 1971 BMW 2002, 1973 BMW R75/5, and 2011 BMW 335d
Previous Other Vehicles: '67 Cougar, '70 911e, '86 Jetta Diesel, '05 and '12 Foresters, et al.
Appreciate 0
Reply

Bookmarks

Tags
335d, dampers, jrz rs1, suspension


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 02:25 PM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST