M140i Upgrades // Part 7: My Own Suspension! *Meister R GT1 & KW V3*

[@misvae1]

Thanks for nice videos! Still hoping you will put out a video on anti roll bars and rear bushings!

[@TimWilliamsHD]

Another absolute banger! Can’t wait for trackdays to re open to see you what you’ve got planned for the Toyo! Hope you’re well Matt

[@CIRCUITDRIVERCARS]

Haha people seem to know I won’t be able to resist tracking it!! Can’t wait for them to reopen, have you got the trackday bug now too?.. 😊

[@TimWilliamsHD]

@@CIRCUITDRIVERCARS yes mate, I’m super late to the party having done football but now I’ve hanged my boots up 10 years before I thought I’d have to, I had to find something else that gets the blood going 🔥😋

[@CIRCUITDRIVERCARS]

@@TimWilliamsHD sorry to hear about the football mate, the positive about being younger is that it’s so much easier to learn how to drive on track! How I wish I’d got out on track when I was 17... 😩

[@tristanmayor6302]

Only just discovered this series. By coincidence I've done almost exactly the same mods to my 240 although not in the same order. I ordered KW V3's in early January (along with M4 LCA & TS and RSF poly bushes) and excitedly anticipating their arrival in 2 more weeks. Even more excited following your positive review. Cheers

[@CIRCUITDRIVERCARS]

Sounds a cracking build Tristan! RSF polybushes?

[@tristanmayor6302]

@@CIRCUITDRIVERCARS Powerflex bushes. LSD was my first mod, being as the whole intention of the car was to get sideways

[@redline589]

@@tristanmayor6302 How did you find the V3's after owning them for a few years?

[@DRIZNISH]

Delivered as expected! The way you present your experiences is very informative as well as mind opening. It is just what the M-Lite community needs / needed. Not just another clickbait KZbinr spending money on camera for likes and views. Also a shame the car is sold but thats life! Question. I don't track my M135i (adaptive suspension and retrofit underbody brace). It is my daily car and used mostly on A/B roads with some twistys thrown in there for good measure. I find the car has heaps of power, more than the car can handle imho (Bootmod3 Stage 1). The chassis doesn't feel confidence inspiring while sometimes feeling like it is fighting itself. It struggles to settle down over bumps and undulations, in summary feels quite lumpy and erratic. the road conditions are not too bad around where I live (Coventry, Midlands). I am considering fitting a Bilstein B12 kit, do you think this is the right way to go about things?

[@vollcare4076]

Would prefer ST-X(A) for the same small budget (ca 900€) - same functionality as KWV1/2 Or Street Comfort (is a more comfortable V2) or V3 if you want to spend a bit more (1400 / 2000€) Or KW DDC (2.500€) if you want to keep the adaptive function KW Clubsport if your focus is more track than on street

[@martinlee7706]

i really like your reviews , the genuine talks and experience and describe by hearts and very details ..... the best youtuber on how to modify ... very helpful, thank you indeed

[@CIRCUITDRIVERCARS]

Thanks Martin that’s very generous of you, exactly what we aim to do, whilst having a good time enjoying the cars with it! 😊

[@vollcare4076]

Rear M140 OEM springs are ca 130N/mm if I remember correctly. V1/2/3 and also ST-X(A) all have same 110N/mm, only Street comfort ist slightly softer with 100N/mm. -> softer rear springs seams to be the main improvement on M140 ! Even track focused KW Clubsport has only 120N/mm at rear Front spring is the same ca 35N/m on all these St/KW springs, only KW Clubsport are harder with about 60 or 70 N/mm. -> so your Meister update seems to match exactly these KW spring rates. Usually these KW guys know there stuff pretty well by simulation as well as testing on hydraulic 7 post test bench and on road

[@CIRCUITDRIVERCARS]

Brilliant info thanks mate, always value your contribution to the channel! I wonder why on Earth BMW settled on such mad rear springs?...

[@vollcare4076]

@@CIRCUITDRIVERCARS maybe the reason for stiff rear spring: Usually you choose stiff anti roll bar at the rear with just medium stiff springs, so you get good traction during acceleration by soft spring as well as good amount of comfort, but still keep the body rolling minimized by the stiff anti toll bar. In case of M140 with huge torque figures and missing LSD out of factory you couldn’t design the anti roll bar with a lot of stiffness, otherwise the traction is really bad if you accelerate out of corners: So to keep the handling OK and avoid ending up in excessive body rolling, BMW probably had to use (overly) stiff springs.

[@CIRCUITDRIVERCARS]

@@vollcare4076 it’s possible / probably but boy did they get it wrong!! 😂 I bet they drive much better with softer rear springs and a thicker ARB, would be a good experiment!

[@vollcare4076]

@@CIRCUITDRIVERCARS that’s actually what BIRDS offer: Softer suspension and stiffer anti toll bar, only makes sense if paired with an LSD, otherwise you’d loose traction

[@CIRCUITDRIVERCARS]

@@vollcare4076 I know theory says so but in practice I can’t see it being any worse!! 🙈 I think the bigger issue with the 140 is that the damper can’t control the spring properly, so the OEM setup just doesn’t work as it should. Gimme an LSD every day of the week though!! 😬

[@2candan1]

Another brilliant video. I’ll miss your 140i content now it’s gone

[@CIRCUITDRIVERCARS]

I miss the car, one day I'll have another lovely BMW daily, life threw a curve-ball though! 🤦‍♂️

[@1bmw_Clubsport]

When are you going to put up the powerflow and antiroll bar video? :-)

[@CIRCUITDRIVERCARS]

Powerflex this week, ARBs next! ...if I don’t moan at me! 😅

[@1bmw_Clubsport]

@@CIRCUITDRIVERCARS sounds good mate.. You should definately look at the rear subframe mounts from millway, i have on my m135i.. That for sure made a huge difference in how the rear end reacts to stearing input. Midcorner stability is improved a lot.. I am also going to upgrade my suspension to the KW 2way clubsport.. I actually wanted to buy meister r gt1, until i saw your review and also the lack of TüV approval.. 👍

[@CIRCUITDRIVERCARS]

@@1bmw_Clubsport ooh Clubsports should be fantastic, Will loved them on his S2000. 😊 Are the millway mounts a full replacement bush? What are they made from?..

[@1bmw_Clubsport]

@@CIRCUITDRIVERCARS yes ive heard that from many people.. They should be compliant enough for street, well at least in Denmark we have sufficient roads with not too many potholes.. The millways are solid aluminium barrels, the funny thing is NVH, isnt amplified too much. Offcourse you can hear more of your suspension and road noise, but its not like a thing that make you think, this is stupid.. Its just a friendly heads up, if you think your car is a bit floaty on the rear, then i personally think this is the right way to go, not the powerflex inserts.. BMW m2, orginally has not any bushings in the rear subframe mounting point to the chassis. This is what in the end made me buy the millways.. But they are a pain to install, but totally worth it. 😊

[@CIRCUITDRIVERCARS]

@@1bmw_Clubsport great info thanks Lars! Guess it all comes down to ratios of use! The difference in the rear end of the M4 was marked, felt connected to your bum and the throttle pedal! That said it was tiresome on long journeys and less pleasant day to day compared to the 140... a real balancing act! The roads here are terrible BTW! Very envious of your smooth roads!

[@TheRobphobos]

I have the GT1's on my 350z (think I was first UK Z with them), my car is leaning more towards track which is where they feel very good to me. Unfortunately on the road it's a little rough but largely due to SPL spherical bushings everywhere 😅 Very happy with their customer service too!

[@CIRCUITDRIVERCARS]

Good to hear Rob, I bet that makes for a cracking car. Always loved Will’s 350! 😊

[@DarrenConquer]

Hi quick question regarding your V3 coilovers. Did you do much tinkering with the settings ie, change the damping and rebound? I’m guessing a bit soft for road use and harder on track?

[@CIRCUITDRIVERCARS]

I didn't use them on track, I had the Meister Rs fitted at that point but played around plenty on the road. On this car and for the fairly poor roads near me, the factory settings made for a very good starting point and I don't think I materially improved it on the road from there.

[@francescosaia4475]

Love this car

[@MrAshLloyd]

Mate this whole series is incredible, you’re very intelligent and love the way you explain it. If I was the go for the GT1 what are the spring rates you would advise then for road and occasional track 3x a year ? F7kg R9kg I think you went for ?

[@CIRCUITDRIVERCARS]

Thanks for the kind words Ashley. I ended up at F5kg and R9kg, though tbh for a mostly road car I think I would choose something like the KW/ST options that use the factory top mounts for a better daily experience.

[@robburton8462]

Thanks for all of the videos on the M140i, i've just binged the whole lot over the last two days! Just out of interest what is that on your seat belt, is it a lock for track driving? Could you maybe let me know how you find them and could you pass on a link for them? I might put them on my 997 if they work well Thanks Rob

[@CIRCUITDRIVERCARS]

Hey Rob, pleased to have entertained/informed/helped a particularly boring spell during lockdown! Good spot on the seatbelt doodah, it’s a CG Lock, it essentially locks out the lap belt so when tightened it holds your hips firmly in place. A very good addition to a fast road and track car, the problem is that they don’t appear to make them any more. I would suggest an eBay saved search with notifications as they do pop up from time to time. Otherwise they may still be available elsewhere in the world, Google might help but unfortunately not readily available last time I looked...

[@robburton8462]

@@CIRCUITDRIVERCARS Great, thanks for the info i'll keep an eye out

[@redline589]

Hey dude, thanks for the info, I purchased the KW V3 based on your experience and what I wanted, im only plan to go on 2 track days a year. could i ask what settings you used on the road and track please.

[@AGM240i]

How are they??

[@redline589]

@@AGM240i They aren't fitted yet, I'm also installing the power flex Polly bush handling kit at the same time. Hopefully in the next few weeks.

[@AGM240i]

@@redline589 i have rear subframe and diff bushings already replaced. So after install please write here what you think about kW v3 for daily and sport use.

[@redline589]

@@AGM240i No problem, how were the bushes?

[@AGM240i]

@@redline589 better feeling much less floaty. I think with the better suspension it will be much better

[@akshadajaywant9817]

👍🏻👍🏻👍🏻👍🏻

[@callumriddell9792]

Loving the content as always, do you think B16s would be comparable to these v3's? i believe the adjustability is on the bottom with them which may make it a more appealing option.

[@CIRCUITDRIVERCARS]

Hello mate, yes the B16s are almost certainly an nice comparable option. Honestly I think the one-way damping adjustment is likely a positive over the two-way adjustability of the KWs as the latter just provides greater opportunity for most of us to get the setup wrong!

[@vollcare4076]

Purpose of V3 is NOT (what a lot o people think) to be more dynamic (more sport/track focused) as V1, V2 or ST-XA cause: V3 uses exact same springs as all of others listed above: Ca 35N/mm front and 110N/mm rear The advantage of the V3 is mainly to deliver more comfort by additional high-speed (bypass) valving which can reduce high speed impacts (curbs, potholes ...) better then standard valves of V1 with just low speed damping valve

[@mantazini]

Bump is low speed control and rebound is high speed not opposite. St Xtas have same v2 , v3 valving , insterst , spring rates linear on front and progressive on rear and are slightly harder to V3s as tbe intension of these is more track focused to V3s . Had both , prefered ST XTAs on M3. V3s are kind of useless in a way being on a softer side originally they don't need separate slow and fast adjustment, you set the bump once and lieve it there most of the times , on track they were sprung way too soft imo .

[@vollcare4076]

@@mantazini you are probably not talking about F20/21 suspension cause on these the exact same spring is used for ST-X(A) and V1,V2, V3 and also DDC. These are slightly progressive on front, on rear these are NOT progressive as you said, here they are 100% linear springs: all with 110N/mm spring rate of main spring. In general There can be low speed and high speed damping for BOTH compression and rebound damping !!! But V1 ans St-X (bot with fixed damping) only habe one valve for each compression and rebound, so same (low speed) damping speed for low and high speed impacts in compression or rebound damping. The better function, or better comfort, of the V3 is based on the more complex valves with: - not fixed but adjustable low speed damping for compression and rebound damping (only rebound on V2, SC, ST-XA), car can be adjusted better to your preference soft or hard in low speed damping - additional (fixed) high speed bypass valve in addition to the adjustable low speed valve -> this high speed bypass can open in case of high speed damper impacts and allow faster travel of the suspension, e.g. if you hit a curb (high speed compression) or a pothole (high speed rebound damping) ...on V4 or V5 you can even adjust the high speed bypass valve, but these are NA for F20/21, only available for e.g. M4

[@CIRCUITDRIVERCARS]

@@vollcare4076 I think this needs to be a pinned comment, brilliant info! How does the V2 fit in? I read on the interweb many moons ago that V2s utilised Koni damping, Chinese whispers? (I’m a big fan on Konis btw)

[@CIRCUITDRIVERCARS]

@@mantazini I’d certainly agree about the V3s being a road coilover that could be used at the track rather than a road & track coilover. The STs make for superb value don’t they! 😊

[@vollcare4076]

@@CIRCUITDRIVERCARS welcome - I also appreciate your channel a lot. As I said already V2 has same springs as V1 or V3 etc, so no differente here. The upgrade of V2 over V1 is the adjustable lowspeed rebound damping where V1 rebound damping is fixed. V3 has on top an adjustable compression (low speed) damping. - Besides the advantage of adjustable low speed damping in V2 or V3 there is another advantage of the adjustable valves: If KW valves are adjustable they also provide this additional (non adjustable) highspeed bypass valve which can open in case of high speed damper impact like curbs/ potholes