More nitty-gritty details on the M4 CSL Suspension

Needsdecaf · 09-07-2023, 01:34 PM

Featured on BIMMERPOST.com

I had posted about Suspension Secrets in the UK in the context of Joe Achilles having his RWD G80 aligned there in the past, and just re-watched that video. In the video, Joe mentions their blog. The latest article is on the M4 CSL intricacies including the difference to the normal M4

https://suspensionsecrets.co.uk/2022...sion-overview/

Few interesting tidbits:

"The front axle was much the same as the standard G82-generation M4, save for a more aggressive front camber setting. This camber increase is built in to wheel hubs that are unique to the M4 CSL."

PLF69 · 09-10-2023, 09:43 AM

Well we already knew all that and a bit lame they are not talking about the different part numbers like the actual shocks, springs, sway bars. I got my CSL on the lift back in November and it's when I noticed the car didn't have helper springs like BMW was talking about in there presentations.

It's more a little marketing article for that particular shop than anything useful.

Here are some pics I took back then and posted in CSL owners thread.

Needsdecaf · 09-10-2023, 10:51 AM

Sorry I was trying to be helpful.

Racer20 · 09-10-2023, 10:53 AM

Helper springs don’t affect performance. They are meant to make sure the spring doesn’t come unseated and rattle around when the wheels go to full droop. It’s purely a function of the spring rate, length, check load, and internal stress. If the spring load is less than some minimum value at full droop, they will add a helper spring to keep it above that value.

It’s likely that BMW defined a range of spring rates they wanted to try early in the program and some of them were under the threshold, so they designed in helper springs. Then when they finished developing the car, they chose a spring that didn’t need a helper to stay seated.

Zero affect to performance.

PLF69 · 09-10-2023, 11:07 AM

Quote:

Originally Posted by Racer20

Helper springs don’t affect performance. They are meant to make sure the spring doesn’t come unseated and rattle around when the wheels go to full droop. It’s purely a function of the spring rate, bright, check load, and internal stress. If the spring load is less than some minimum value at full droop, they will add a helper spring to keep it above that value.

It’s likely that BMW defined a range of spring rates they wanted to try early in the program and some of them were under the threshold, so they designed in helper springs. Then when they finished developing the car, they chose a spring that didn’t need a helper to stay seated.

Zero affect to performance.

Yup

PLF69 · 09-10-2023, 11:09 AM

Quote:

Originally Posted by Needsdecaf

Sorry I was trying to be helpful.

Not against you or anything, I guess if something sounds new or special it's a good sell to put it on the front page to get more traffic, we sometimes forget this forum is a business.

kgelfen360 · 09-10-2023, 11:25 AM

Quote:

Originally Posted by PLF69

Not against you or anything, I guess if something sounds new or special it's a good sell to put it on the front page to get more traffic, we sometimes forget this forum is a business.

I don’t think Needsdecaf sells anything though.

PLF69 · 09-10-2023, 11:28 AM

Quote:

Originally Posted by kgelfen360

I don’t think Needsdecaf sells anything though.

I don't think he put it on the front page himself either, unless he is a moderator or something.

Needsdecaf · 09-10-2023, 11:29 AM

Quote:

Originally Posted by PLF69

I don't think he put it on the front page himself either, unless he is a moderator or something.

Nope. Not me. Was neat to see details I was previously u aware of.

shawnhayes · 09-10-2023, 12:24 PM

Thread that starts off weird, and then quickly becomes worth a million likes.

Strong work, forum

Shawn

Boogie2121 · 09-10-2023, 01:03 PM

AST suspension, Michelins, Monoballs, CS flash - thank me later!

HP Autosport · 09-10-2023, 03:15 PM

Quote:

Originally Posted by PLF69

Well we already knew all that and a bit lame they are not talking about the different part numbers like the actual shocks, springs, sway bars. I got my CSL on the lift back in November and it's when I noticed the car didn't have helper springs like BMW was talking about in there presentations.

It's more a little marketing article for that particular shop than anything useful.

Here are some pics I took back then and posted in CSL owners thread.

It does have the helper springs. It's in one of your photos.

dezzracer · 09-10-2023, 03:22 PM

Quote:

Originally Posted by Boogie2121

AST suspension, Michelins, Monoballs, CS flash - thank me later!

Lol. I’m not as privy to the CSL technical details as you guys but sounds about right. As an F80 CS owner (I paid $10k under MSRP) the approximate $16k I paid over an F80 comp was worth it. When I added up the special factory parts (including $5,500 carbon hood) special light weight wheels, unique interior and seats , CS tuning, rarity value, etc. it seemed fair. We don’t know how many got their CSL’s at MSRP but I’m certain some paid over. BMW sure is proud of their CS/CSL models. Discovering/learning more about parts unique to those models does help ease the premium price pain tho.

PLF69 · 09-10-2023, 03:29 PM

Quote:

Originally Posted by HP Autosport

It does have the helper springs. It's in one of your photos.

It's just a rubber isolator/absorber on the coil.

tfunk88 · 09-10-2023, 05:09 PM

Quote:

Originally Posted by HP Autosport

It does have the helper springs. It's in one of your photos.

I could be wrong but all I’m seeing is a progressive spring 🤷&zwj;♂️

GT3M2 · 09-10-2023, 07:19 PM

Quote:

Originally Posted by tfunk88

I could be wrong but all I’m seeing is a progressive spring 🤷&zwj;♂️

I see what you see.
-GT3M2

jmg · 09-10-2023, 11:24 PM

Aggressive camber is pretty much the first mod for any track minded G8X no surprise there. I wonder what the actual spring rates are and what camber they ship at? Still not adjustable though?

Matt@Evolve · 09-11-2023, 12:15 AM

Not adjustable, fixed by a different hub assembly.

Bee Pee · 09-11-2023, 05:26 AM

Quote:

Originally Posted by Matt@Evolve

Not adjustable, fixed by a different hub assembly.

Matt - is the intent to retrofit the m3 CS hub carriers / swivels to add camber to Evolve’s M3T CSL ??

amrazM · 09-11-2023, 07:10 AM

a csl without clubsport suspension, really is just an upbadged m4 for the masses. either way it doesnt matter, the folks buying it after the market adjustments arent taking it to the track either way.

PLF69 · 09-11-2023, 08:50 AM

Quote:

Originally Posted by jmg

Aggressive camber is pretty much the first mod for any track minded G8X no surprise there. I wonder what the actual spring rates are and what camber they ship at? Still not adjustable though?

My guess from eyeing it is around -2.5, felit like it too.

Unfortunately I did not keep my CSL but I would of out it on a an alignment rack eventually.

Highlander-M4 · 09-12-2023, 03:31 AM

A standard F80 or G80 with camber plates (-2.5 street, -4.0 to -5.0 track day settings) and monoball), along with a more aggressive Toe Out, track bushings, and sub 110 compound tires will beat any CS or CSL at a fraction of the cost. With no fancy suspension upgrades. People rush to hand over money, without understanding the importance of GEOMETRY.

09-07-2023, 01:34 PM	#1
Needsdecaf Major General 6608 Rep 6,701 Posts Drives: 2024 G80 Comp xDrive Join Date: Feb 2011 Location: The Woodlands, TX iTrader: (0)	More nitty-gritty details on the M4 CSL Suspension Featured on BIMMERPOST.com I had posted about Suspension Secrets in the UK in the context of Joe Achilles having his RWD G80 aligned there in the past, and just re-watched that video. In the video, Joe mentions their blog. The latest article is on the M4 CSL intricacies including the difference to the normal M4 https://suspensionsecrets.co.uk/2022...sion-overview/ Few interesting tidbits: "The front axle was much the same as the standard G82-generation M4, save for a more aggressive front camber setting. This camber increase is built in to wheel hubs that are unique to the M4 CSL."
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09-10-2023, 09:43 AM	#2
PLF69 Colonel 3768 Rep 2,700 Posts Drives: 2023 M3 Join Date: Jan 2017 Location: Quebec iTrader: (0)	Well we already knew all that and a bit lame they are not talking about the different part numbers like the actual shocks, springs, sway bars. I got my CSL on the lift back in November and it's when I noticed the car didn't have helper springs like BMW was talking about in there presentations. It's more a little marketing article for that particular shop than anything useful. Here are some pics I took back then and posted in CSL owners thread. Attached Images __________________ Fun/HPDE: 2023 M3 6MT Individual Malachite Past:2023 M4 CSL, 2022 M4C Vert, 2020 M340i, 2018 M2, 2015 M235i, 2008 135i 550whp Daily: 2023 X5 45e Daily/Family: 2021 Atlas Cross Sport 3.6 Last edited by PLF69; 09-10-2023 at 09:51 AM..
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09-10-2023, 10:51 AM	#3
Needsdecaf Major General 6608 Rep 6,701 Posts Drives: 2024 G80 Comp xDrive Join Date: Feb 2011 Location: The Woodlands, TX iTrader: (0)	Sorry I was trying to be helpful.
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09-10-2023, 10:53 AM	#4
Racer20 Major 1030 Rep 1,190 Posts Drives: F80 M3, 228i THP, E46 ZHP Join Date: May 2009 Location: Ann Arbor, MI iTrader: (0)	Helper springs don’t affect performance. They are meant to make sure the spring doesn’t come unseated and rattle around when the wheels go to full droop. It’s purely a function of the spring rate, length, check load, and internal stress. If the spring load is less than some minimum value at full droop, they will add a helper spring to keep it above that value. It’s likely that BMW defined a range of spring rates they wanted to try early in the program and some of them were under the threshold, so they designed in helper springs. Then when they finished developing the car, they chose a spring that didn’t need a helper to stay seated. Zero affect to performance. __________________ 2015 M3, 2005 330i ZHP, 2015 228i 6MT Track Handling Pack, 2007 M Coupe (Sold)
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09-10-2023, 12:24 PM	#10
shawnhayes Major 1834 Rep 1,327 Posts Drives: 22M5 CS,23X5E,24M3 CS,24 i4 Join Date: Aug 2015 Location: Virginia iTrader: (0)	Thread that starts off weird, and then quickly becomes worth a million likes. Strong work, forum Shawn
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09-10-2023, 01:03 PM	#11
Boogie2121 Lieutenant 1139 Rep 439 Posts Drives: BMW X5M Join Date: Oct 2021 Location: Chicago iTrader: (0)	AST suspension, Michelins, Monoballs, CS flash - thank me later!
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09-10-2023, 11:24 PM	#17
jmg Lieutenant General 18711 Rep 14,115 Posts Drives: G82 M4C X-Drive Join Date: Mar 2013 Location: Orange County, CA iTrader: (1) Garage List 2022 G82 M4C X-Drive [9.85] 2018 F80 M3 CS [9.87] 2019 i3 BEV [0.00]	Aggressive camber is pretty much the first mod for any track minded G8X no surprise there. I wonder what the actual spring rates are and what camber they ship at? Still not adjustable though? __________________ 2022 G82///M4 Competition X-Drive - KW-HAS, EBC Bluestuff, Millway Race Camber Plates, Cup2 Connect, PSI High Flow Midpipe, Lightweight Front Lip, M Perf Flow Through Wing Previous • 2018 F80 ///M3 CS • 2016 F80 ///*M3 IG: Raging_G82
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09-11-2023, 12:15 AM	#18
Matt@Evolve BimmerPost Supporting Vendor 1973 Rep 520 Posts Drives: F82 M4, E36 M3 Touring, Z3 Join Date: May 2022 Location: Luton, UK iTrader: (0)	Not adjustable, fixed by a different hub assembly.
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09-11-2023, 07:10 AM	#20
amrazM mTekMods 2148 Rep 2,905 Posts Drives: like a granny. Join Date: Jan 2010 Location: Manhatan iTrader: (1)	a csl without clubsport suspension, really is just an upbadged m4 for the masses. either way it doesnt matter, the folks buying it after the market adjustments arent taking it to the track either way. __________________ 2011 Frozen Black/Fox Red E90 M3 650+WHP G-Power Supercharged First DCT to Manual Conversion Worldwide KW CS, BBS RI-A, BW Headers, Snow 2.5
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09-12-2023, 03:31 AM	#22
Highlander-M4 New Member 27 Rep 25 Posts Drives: BMW M4 Join Date: Apr 2020 Location: London, UK iTrader: (0)	A standard F80 or G80 with camber plates (-2.5 street, -4.0 to -5.0 track day settings) and monoball), along with a more aggressive Toe Out, track bushings, and sub 110 compound tires will beat any CS or CSL at a fraction of the cost. With no fancy suspension upgrades. People rush to hand over money, without understanding the importance of GEOMETRY.
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