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      03-02-2024, 04:02 PM   #23
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Originally Posted by M3SQRD View Post
I was typing my response when you mentioned wanting to run a 5” main spring

If that’s one of your requirements then going down on the front rate isn’t really possible. 700 lbf/in would be cutting it really close…I just looked up the spring travel of a 5” 800 lbf/in vs. 5” 700 lbf/in. The 700 has more travel (2.937”), albeit small, than the 800 (2.889”) so the concern is coil bind, not piston travel? Is the 5” spring totally unloaded at full droop? I’m assuming no helper to maximize tire width? Do you run a bump stop with a 5” main spring? Trying to understand how much piston travel is used up when going from full droop to fully loaded. Assuming 50-50 weight distribution and 3800 lbf weight, that puts a static load of 950 lbf per corner so static deflection is 950/700 = 1.36”. This leaves 1.57” of travel. Fd = 700*1.57 = 1099 lbf. Need to do more math and estimation to see what lateral accel is needed to reach 1099 lbf…
I love your quantitative approaches to things -- yes, concern is coil bind. I can't confirm the fully-unloaded-at-full-droop question off top of my head, but I am running a helper which is what BW advised, so I presume the answer is yes.

No bump stops -- for reasons I don't fully understand, it seems this is par for the course with MCS setups around here (and again, BW says not needed)
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      03-02-2024, 04:43 PM   #24
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Quote:
Originally Posted by jfritz27 View Post
I love your quantitative approaches to things -- yes, concern is coil bind. I can't confirm the fully-unloaded-at-full-droop question off top of my head, but I am running a helper which is what BW advised, so I presume the answer is yes.

No bump stops -- for reasons I don't fully understand, it seems this is par for the course with MCS setups around here (and again, BW says not needed)
My day job carries over into everything I do

In almost all cases, especially on 2/3/4WRs, coil bind occurs before max strut travel is reached. I looked at using a bump stop on my e92 M3 a while ago and it required a relatively long bump stop to get it to engage before coil bind. Thought about using bump stop shims but, at the time, I had trouble finding off-the-shelf bump stops for the MCS piston rod diameter and correct length so I dropped it. Some race shops do use bump stops with MCS dampers and it’s usually with short main springs with helper springs or tender springs. The advantage to a bump stop on a setup where the main spring binds first is to eliminate/minimize the impact load and the sudden loss of grip if coil bind occurs.
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      03-02-2024, 05:02 PM   #25
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Nice -- you kept spring rates the same? That will be a nice controlled experiment, please share how it feels once you get enough seat time
No. Moved from 800f/700r to 1000f/900r. I also did the full gt more kit and replaced all other arms and bushings with hiems or bearings.

Not to open another can of worms for you but if you are going to redo the suspension again why not look at the gtmore setup? Sure it's more, but not much more in the scheme of all new 2 way remotes. Although I am sure street compliance will go out the window.

I think going from 2wr to 3 wr if you ever want to in the future is then just new canisters.
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      03-02-2024, 05:23 PM   #26
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Et tu, Brute?! Yeah, I hear on you on 2w vs 3w, but if I do this, it's going to be the last goddam time, and given how much I'd already be dumping in, I figure I might as well go all-in.

I forget, you're running a 5" in front and no issues with a 700 lb spring?

Looks like I might be begging BW for a little discount come this Black Friday....
Oh yah I hear you there and agree. If for some reason you end up gong 2W, I saw it mentioned but I think the only difference in hardware is in the canister, I think back to the BW GTMore vid for gridlife where they had to run 2W and it was a super easy canister swap.

I’m Running 6in front, BW advised me not to go 5in unless the rate was 850 or above. Having been in and around a whole bunch of MCS setups now, 700/600 seems to be where most people like to max out for a dual purpose car. But since you have the 800/700 setup right now, see how the extra travel and running closer to 100 psi works out - could just do the trick.
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      03-02-2024, 05:55 PM   #27
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Oh yah I hear you there and agree. If for some reason you end up gong 2W, I saw it mentioned but I think the only difference in hardware is in the canister, I think back to the BW GTMore vid for gridlife where they had to run 2W and it was a super easy canister swap.

I’m Running 6in front, BW advised me not to go 5in unless the rate was 850 or above. Having been in and around a whole bunch of MCS setups now, 700/600 seems to be where most people like to max out for a dual purpose car. But since you have the 800/700 setup right now, see how the extra travel and running closer to 100 psi works out - could just do the trick.
Yes, it’s just a remote reservoir swap. However, the cost delta between upgrading from a 2WR to 3WR is the same as the price difference between a new 2WR setup and a new 3WR setup!
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      03-03-2024, 08:17 AM   #28
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Originally Posted by M3SQRD View Post
Yes, it’s just a remote reservoir swap. However, the cost delta between upgrading from a 2WR to 3WR is the same as the price difference between a new 2WR setup and a new 3WR setup!
About $2000. Better than a new set of coilovers!
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      03-03-2024, 09:00 AM   #29
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About $2000. Better than a new set of coilovers!
Is that an estimate or an actual quoted price? That’s more than the cost difference between a new set of 2WR and 3WR.
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      03-03-2024, 01:45 PM   #30
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Was just looking at the difference between 2 and 3 way
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      03-03-2024, 02:07 PM   #31
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Originally Posted by b_w. View Post
Was just looking at the difference between 2 and 3 way
You’re right. Price difference is $2060. They price the upgrades so you end up paying the same whether you bought the 4WR (although this is more than just a reservoir change) to begin with or worked your way up from 2WR to 3WR to 4WR.

$2k sounds like a lot when they’re “just” changing the internal compression valve stack and adding a new shaft to accommodate a second external knob
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      06-17-2024, 08:37 AM   #32
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jfritz27
I see you made a post on using a 20 cf Nitrogen tank. That must mean you went with the remotes. Please tell us how they are on the street vs the 2wnr. Did they get you the compliance you were wanting?

I also use mine as a daily driver. So I like to be able to take the family out to dinner on a Friday night, then go out on Saturday to beat up on the GT3s.
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      06-17-2024, 10:12 AM   #33
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Quote:
Originally Posted by MAG22 View Post
jfritz27
I see you made a post on using a 20 cf Nitrogen tank. That must mean you went with the remotes. Please tell us how they are on the street vs the 2wnr. Did they get you the compliance you were wanting?

I also use mine as a daily driver. So I like to be able to take the family out to dinner on a Friday night, then go out on Saturday to beat up on the GT3s.
Thanks for the reminder to come update here... yes! I've put a good number of miles on them now, and I would say that if you have the means, the benefits for a daily driver on crappy roads justifies the cost. This is with running the canisters at around 90 psi on the street. Changing back/forth is not a huge deal once you get the hang of it. Obviously it still feels quite firm (with 800/700 spring rates), but the added volume of the remote reservoirs + the low gas pressure really nicely takes the edge off the sharp road imperfections (with the lower gas pressure I think the dominant contributor to that based on my experience). If I had to put a number on it, the "harshness" of the sharp stuff is probably reduced 20-30%.

The front canisters are tucked under the front fenders (thanks to D_SheerDrivingPleasure). I dremeled a little cutout and fitted 90-deg Shrader extensions, making pressure changes fairly painless.

90-deg extenders:
https://www.amazon.com/dp/B08PYY8BHL...t_details&th=1

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      06-19-2024, 02:11 AM   #34
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Quote:
Originally Posted by jfritz27 View Post
Thanks for the reminder to come update here... yes! I've put a good number of miles on them now, and I would say that if you have the means, the benefits for a daily driver on crappy roads justifies the cost. This is with running the canisters at around 90 psi on the street. Changing back/forth is not a huge deal once you get the hang of it. Obviously it still feels quite firm (with 800/700 spring rates), but the added volume of the remote reservoirs + the low gas pressure really nicely takes the edge off the sharp road imperfections (with the lower gas pressure I think the dominant contributor to that based on my experience). If I had to put a number on it, the "harshness" of the sharp stuff is probably reduced 20-30%.

The front canisters are tucked under the front fenders (thanks to D_SheerDrivingPleasure). I dremeled a little cutout and fitted 90-deg Shrader extensions, making pressure changes fairly painless.

90-deg extenders:
https://www.amazon.com/dp/B08PYY8BHL...t_details&th=1

I use same spring rate as you with pressures of 150psi front and 125psi rear, and I am impressed, this suspension is magical, before I had kw competition with a lower spring rate, and it was unbearable to drive on bad roads, I have placed the reservoirs in the carbon bar, I will make some 3d supports










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      06-19-2024, 10:46 AM   #35
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Originally Posted by Track/S View Post
I use same spring rate as you with pressures of 150psi front and 125psi rear, and I am impressed, this suspension is magical, before I had kw competition with a lower spring rate, and it was unbearable to drive on bad roads, I have placed the reservoirs in the carbon bar, I will make some 3d supports










I plan to order some of these canister mounts/supports from you with the next parts order. Any chance you have some Nitron R3 canisters to model?

As a side question. Can you use a C02 canister for nitrogen? I have a 20lb tank that I had for a fish tank sitting around. Besides being a pain to move around I'm wondering if it can be repurposed. I plan to order a nitrogen control system for filling reservoirs.
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      06-19-2024, 11:47 AM   #36
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Originally Posted by medphysdave View Post
I plan to order some of these canister mounts/supports from you with the next parts order. Any chance you have some Nitron R3 canisters to model?

As a side question. Can you use a C02 canister for nitrogen? I have a 20lb tank that I had for a fish tank sitting around. Besides being a pain to move around I'm wondering if it can be repurposed. I plan to order a nitrogen control system for filling reservoirs.
I have an r3 for m3 e92 in the workshop, and the reservoir seems like it cannot be recharged:






To recharge my mcs I am using the equipment I have for welding:


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      06-19-2024, 11:50 AM   #37
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Thanks. They might not be fillable. I assumed all remote canisters were fillable, but I'm inexperienced with suspension so probably mistaken.
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      06-19-2024, 12:29 PM   #38
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I have an r3 for m3 e92 in the workshop, and the reservoir seems like it cannot be recharged:






To recharge my mcs I am using the equipment I have for welding:


Yes. Nitron R3 has non adjustable remote reservoirs. I’d say it’s around 50/50 whether remote reservoirs are N2 adjustable.
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      06-19-2024, 12:30 PM   #39
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Thanks. They might not be fillable. I assumed all remote canisters were fillable, but I'm inexperienced with suspension so probably mistaken.
I believe the Nitron standard R3 on the f8x uses piggyback reservoirs, not remote reservoirs.
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      06-19-2024, 12:32 PM   #40
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I believe the Nitron standard R3 on the f8x uses piggyback reservoirs, not remote reservoirs.
They can be specced with remote quick connects. It isn't cheap, but I'm lazy and hoping it will make adjustments easier.
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      06-19-2024, 12:37 PM   #41
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They can be specced with remote quick connects. It isn't cheap, but I'm lazy and hoping it will make adjustments easier.
Yes, remote reservoirs are an option on the R3. lol it’s not difficult to reach around and make adjustments. Remotes do make things a bit easier to adjust.
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      06-19-2024, 01:07 PM   #42
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Yes, remote reservoirs are an option on the R3. lol it’s not difficult to reach around and make adjustments. Remotes do make things a bit easier to adjust.
The etron R3s are currently being tested and they are the non remote. Since they are being dialed in on a CS. I'll talk to Jason about the value proposition for someone like me that will likely use his settings for various scenarios. I dont know how much adjustment I'll be doing. Track, spirited hills, DD. If reaching around isn't a big task it might be worth it for me to not go with remote canisters. I can't recall if axle lift requires canisters.
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      06-19-2024, 04:34 PM   #43
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Originally Posted by medphysdave View Post
The etron R3s are currently being tested and they are the non remote. Since they are being dialed in on a CS. I'll talk to Jason about the value proposition for someone like me that will likely use his settings for various scenarios. I dont know how much adjustment I'll be doing. Track, spirited hills, DD. If reaching around isn't a big task it might be worth it for me to not go with remote canisters. I can't recall if axle lift requires canisters.
For high-end race dampers there will not be difference between base, zcp and cs damping curves. There’s sufficient range of motion to get LS and HS in the underdamped and critically damped ranges you’re dialing in with a wide range of spring rates. For example, the same MCS 2/3WR dampers can be used on the e9x M3, f8x, f2x, f3x and f4x models.

Lift kit doesn’t require remote reservoirs.
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      06-19-2024, 06:22 PM   #44
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For high-end race dampers there will not be difference between base, zcp and cs damping curves. There’s sufficient range of motion to get LS and HS in the underdamped and critically damped ranges you’re dialing in with a wide range of spring rates. For example, the same MCS 2/3WR dampers can be used on the e9x M3, f8x, f2x, f3x and f4x models.

Lift kit doesn’t require remote reservoirs.
I meant they are tuning the valving and spring rates to work well with the EDC controlled rebound on the M2CS. I think that is the main variable. How will the three electronic suspension settings interact with everything else.
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