Performance suspension + Non RFT

gemini.m3 · 03-26-2015, 10:46 PM

Anybody have this setup? how does it ride? Looking at this specific setup with the super sport tires. I hear when you go non RFT on stock m-sport / sport suspension car feels really funny, does anyone experience this with performance susp?

andrey_gta · 03-27-2015, 08:48 AM

From what I heard - great.
The Perf shocks are well done

BMW135pls · 03-28-2015, 10:54 PM

I'm pretty new to this exact setup, but I do have some input on it anyway. The stock car on RFTs actually made me physically dizzy from driving on our local roads, which are not well taken care of on the grand scale. It was stiff, but in a bad way. I switched to Non-RFTs last year and the ride quality increase was large due to the softer sidewalls, but the performance increase was still less than expected. I believe this was due to the fact that the stock suspension was designed with RFTs in mind, so it was pretty soft by sports car standards and the rear end was very loose. Just a few days ago I got the M RSFB bushings installed, along with a new set of Michelin PSS tires, and it is clear that the suspension can now handle the power the car has. No more sidekick on launch, and no more snake on straight pulls.

I had the bushings installed at a local performance shop, and they actually called me saying that they didn't think the work would be worth it, since the M bushings are rubber, same as stock, but I wanted them installed anyways. After the install they said they could clearly see the reason for the upgrade, the stock bushings were mostly empty space, the M bushings were much more hardy by comparison. So that's the main difference really, the stock bushings are not rated for Non-RFTs or really for the power the car can generate in general. You can compress them with your thumbs, that's probably not good?

Long story short, I spent the day trolling around town with a friend of mine who has a lot of experience with sports cars and has an obvious lean toward "American Muscle" styled vehicles, but both of us were very impressed with the performance, both in handling and power.

John_01 · 03-29-2015, 07:58 AM

I have used the performance suspension on my car. I think its a really good improvement over the factory suspension. It is firmer - more like you would expect in a performance car. It will trade off some ride quality when you drive on rough roads, but still very reasonable in most situations. I recommend changing the tires to conventional performance / sport tires. The tires themselves won't cause any problem if you choose good ones and keep the pressure up a bit to 36PSI - 38PSI front and rear.

The performance suspension is not a perfect solution for all issues with 1 series handling. 1) There is still some weirdness with the loose feeling in the rear of the car. You need to get upgrade rear sub-frame bushings to solve that. 2) The car still a little bit too much body roll - my opinion. 3) The steering is still a bit soft and lacking feel and responsiveness.

BMW135pls · 03-29-2015, 08:54 AM

Quote:

Originally Posted by John_01

I have used the performance suspension on my car. I think its a really good improvement over the factory suspension. It is firmer - more like you would expect in a performance car. It will trade off some ride quality when you drive on rough roads, but still very reasonable in most situations. I recommend changing the tires to conventional performance / sport tires. The tires themselves won't cause any problem if you choose good ones and keep the pressure up a bit to 36PSI - 38PSI front and rear.

The performance suspension is not a perfect solution for all issues with 1 series handling. 1) There is still some weirdness with the loose feeling in the rear of the car. You need to get upgrade rear sub-frame bushings to solve that. 2) The car still a little bit too much body roll - my opinion. 3) The steering is still a bit soft and lacking feel and responsiveness.

The M sway bars would probably be the fix for no. 2/3 right? Or at least I think it'll help, maybe 2 moreso than 3 though. 3 might require the M control arms and a bit more aggressive alignment? I don't know the exact solutions, being that I'm still pretty new to this. You are right though, the M RSFB absolutely solve the issue of the wobbly back end.

John_01 · 03-29-2015, 08:12 PM

Quote:

Originally Posted by BMW135pls

The M sway bars would probably be the fix for no. 2/3 right? Or at least I think it'll help, maybe 2 moreso than 3 though. 3 might require the M control arms and a bit more aggressive alignment? I don't know the exact solutions, being that I'm still pretty new to this. You are right though, the M RSFB absolutely solve the issue of the wobbly back end.

Unfortunately the RSFB is an expensive job if you get the M3 ones put in by a shop. Next to upgrading dampers, I think its one of the best mods you can do, no matter whether you decide on genuine M3 bushings, or other aftermarket options. It simply makes the rear of the car track more predictably even in daily driving situations.

If you want responsive steering you will appreciate the M3 front arms too. It can make sense to have them put in if you are replacing the front struts as there isn't much additional labour. The arms work because they eliminate the soft (fluid filled) front bushings that are used to absorb the harshness of the RFT tires. The extra camber gained with these arms also makes a big change to the steering response.

The front M3 front sway bar is really up to your preference. It works well together with the M3 front arms in a road car situation. However, the performance suspension kit includes an upgraded sway bar, so you should probably try that first.

MikesBMW · 03-29-2015, 08:25 PM

I'm considering RSFB what should I expect to pay for the install at an Indy?

BMW135pls · 03-29-2015, 08:27 PM

Quote:

Originally Posted by BMW135iMike

I'm considering RSFB what should I expect to pay for the install at an Indy?

About 6-7 hours is estimated.

03-26-2015, 10:46 PM	#1
gemini.m3 Major 1497 Rep 1,297 Posts Drives: 2022 M3 xDrive comp Join Date: Aug 2014 Location: Miami, FL iTrader: (8)	Performance suspension + Non RFT Anybody have this setup? how does it ride? Looking at this specific setup with the super sport tires. I hear when you go non RFT on stock m-sport / sport suspension car feels really funny, does anyone experience this with performance susp? __________________ 2022 M3 xDrive Comp 2020 M2 CS (retired) 2018 M3 Comp (retired) 2015 335i (retired)
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03-27-2015, 08:48 AM	#2
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]	From what I heard - great. The Perf shocks are well done __________________ 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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03-28-2015, 10:54 PM	#3
BMW135pls First Lieutenant 90 Rep 341 Posts Drives: Bucket of screws and sadness Join Date: Jul 2014 Location: NJ, USA iTrader: (0)	I'm pretty new to this exact setup, but I do have some input on it anyway. The stock car on RFTs actually made me physically dizzy from driving on our local roads, which are not well taken care of on the grand scale. It was stiff, but in a bad way. I switched to Non-RFTs last year and the ride quality increase was large due to the softer sidewalls, but the performance increase was still less than expected. I believe this was due to the fact that the stock suspension was designed with RFTs in mind, so it was pretty soft by sports car standards and the rear end was very loose. Just a few days ago I got the M RSFB bushings installed, along with a new set of Michelin PSS tires, and it is clear that the suspension can now handle the power the car has. No more sidekick on launch, and no more snake on straight pulls. I had the bushings installed at a local performance shop, and they actually called me saying that they didn't think the work would be worth it, since the M bushings are rubber, same as stock, but I wanted them installed anyways. After the install they said they could clearly see the reason for the upgrade, the stock bushings were mostly empty space, the M bushings were much more hardy by comparison. So that's the main difference really, the stock bushings are not rated for Non-RFTs or really for the power the car can generate in general. You can compress them with your thumbs, that's probably not good? Long story short, I spent the day trolling around town with a friend of mine who has a lot of experience with sports cars and has an obvious lean toward "American Muscle" styled vehicles, but both of us were very impressed with the performance, both in handling and power. __________________ Model: '08 135i N54 6AT Coupe ///M Sport - E85 + 93 = E30 Mods: AA DPs + Gen I - BMS JB4 (Race + Map 2) + DCI + OCC - Cobb CP - ///M RSFB + Front Control Arms - Koni Yellow - Swift Spec R - Vorshlag camber plates - MPSS 225/255 - x-ph Angel Eyes 160w Last edited by BMW135pls; 03-29-2015 at 12:03 AM..
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03-29-2015, 07:58 AM	#4
John_01 Colonel 232 Rep 2,643 Posts Drives: E90 325i, E82 135i Join Date: Mar 2009 Location: Sydney, Australia iTrader: (0)	I have used the performance suspension on my car. I think its a really good improvement over the factory suspension. It is firmer - more like you would expect in a performance car. It will trade off some ride quality when you drive on rough roads, but still very reasonable in most situations. I recommend changing the tires to conventional performance / sport tires. The tires themselves won't cause any problem if you choose good ones and keep the pressure up a bit to 36PSI - 38PSI front and rear. The performance suspension is not a perfect solution for all issues with 1 series handling. 1) There is still some weirdness with the loose feeling in the rear of the car. You need to get upgrade rear sub-frame bushings to solve that. 2) The car still a little bit too much body roll - my opinion. 3) The steering is still a bit soft and lacking feel and responsiveness.
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03-29-2015, 08:25 PM	#7
MikesBMW Banned 318 Rep 1,410 Posts Drives: X3 M40i Join Date: Jul 2010 Location: Ohio iTrader: (1) Garage List 2019 BMW X3 M40i [0.00] 2017 BMW X1 [0.00]	I'm considering RSFB what should I expect to pay for the install at an Indy?
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