Evo Magazine's Review of the BMW Performance Suspension

[bmw330d]

For me having read the article in question I have to agree with others, changing the wheels and tyres then the suspension without a new benchmark figure in between, which incidently they could not get because of the weather, gives no proof as to what the suspension has done for the car.

Tyres have a massive impact on lap times, I for one have data logs at Donnington showing 2-3 seconds a lap of difference between one sticky tyre and another on the same day on the same car.

[bmw330d]

Just another point to back up the no two tyres are the same rule.

The UTQG rating on the Bridgestone is 140, the Dunlop is 280 (both figures taken from tire rack) this proves the Dunlop is a harder tyre. The Bridgestone will grip better but offer a faster rate of wear.

[Justin(OKC)]

Originally Posted by bradford

Stock 135i ARBs?

I'll answer for him....they are running UUC ARB's. If you do a little searching, brracing has posted a lot of info on their car. I've done some similar things but my approach has been a bit different. Granted, my car is not quite the track rat that their car is

[Mark M]

While I can't comment on lap times, I can comment on the KWs.

I have had the KW V2 setup on my car since 1800 miles, hands down this has been one of the best automotive mods I have ever done. Very robust and well rounded setup. Dial soft for daily use / comfort, dial firm and the suspension is taught and flat for real performance driving.

[///M1]

Yes, the suspension is the achiles heel IMO on this car, and with power mods it only becomes more apparent. Any form of aftermarket suspension should be an improvement. I am likely going to go the BMW PS route while also adding some M3 parts (control arms, rear bushings, etc.)

[mineo77]

how easy is it to adjust the dampening on the KW V2's?

[BMW86]

Originally Posted by mineo77

how easy is it to adjust the dampening on the KW V2's?

+ 1

Would like to see a video of how it is done.

[FlyingScot]

I have the KW V3 on my S2000 which is setup as a track car. The front adjustment is very easy, just open the hood and right there on strut tower - just like in the BMW.

The rears are a PIA as you open the trunk and access on top of rear wheel well - I have NOT torn my BMW trunk apart yet to see how to access the rear wheel tower tops...if anyone has done this chime in. I'm guessing it will be similar.

Once you have access it is only a few turns either way. And yes, I can attest that the KWs are pretty awesome shocks - why I'm considering for the 135. I'm a little hesitant thought as there doesn't seem to be a lot of info on tuning the 1-series suspension - which is critical if these are going to be an improvement. With the S2K, I had access to a lot of experienced suspension tuners and was able to setup the car with bigger tires (had 215/245 17" and went to 235 / 255 17"), adjustable front anti-sway, alignment changes, and cross-balance. I also almost doubled the spring rate and I'm still dialing in the oversteer ( still a bit tail happy). Track time is letting me setup to my style (it is supercharged to put out 304 hp at wheels).

Still undecided if I want to go down this path with the BMW - this is a daily driver that may see light track duty with my wife driving. Suspension is a package and not sure I could get it right with just KWs. ....must resist...no mods on new BMW ...(I dropped suspension, replaced clutch, put in SC on S2K at 5000K miles and said to heck with the warranty)....can't work on the 135 as easily as the S2K.

[///M1]

New month, new issue, new discussion of the Evo 135i project car

This month, after the suspension, it gets the power kit. And finally some real tures next month, all of that ought to improve the lap times considerably!

[rsjean]

Originally Posted by ptack

So far it seems that none of the BMW upgrades for the 135i do anything at all to significantly improve performance. I wonder if that's no accident. Can't wait to read about the engine upgrade.

From European Car magazine....

"Our biggest complaint with the 135i didn't rest with the engine but rather with the car's chassis dynamics. As one seasoned journalist put it: "It understeers like a pig." I can tell you firsthand it's nearly impossible to rotate the factory car without throwing it horribly out of shape. Couple this tendency to plow with the standard factory run-flat tires and you've got a formula for less than desirable track handling.

Madness addressed the issue with a full KW Suspension V3 coilover kit. In front, a BMW Performance brace was bolted in to tie the upper suspension together and tighten up turn-in. Adjustable camber plates were also added (set 2 degrees negative) and the front stabilizer bar replaced with a 35mm Hotchkis piece. In back, the factory bar was left in place but disconnected at one side, effectively rendering it inoperative. While we might not recommend this setup for everyday street use, it allows the rear end to be more easily unsettled, relying on the improved rigidity of the front engine to keep the chassis flat as the rear tires skate out.

The wheels and tires needed to be replaced, and Madness did it with Breyton GTS-Rs, which weigh a feathery 18 pounds each, surrounded with Continental SportContact3s. Inside those, the already beefy factory brakes were upgraded with slotted rotors, Cool Willey race pads, and stainless steel lines. The brake setup is definitely designed to be track-friendly, and you might say the tires alone could account for a 50 percent improvement in overall handling."

[Tallest]

difference in times can be attributed to:

1. difference in wheel alignments after suspension change
2. difference in weather
3. difference in track (or how green it was)

Overall what CAR wrote I think is pretty reliable since they know what they're doing.

[///M1]

Well, another month passed by, and the poor guys at Evo magazine are having problems with the in-fleet 135i. After they installed BMW's Powerpack, they went on the track and halfway through the 2nd lap car goes limp, and following msg appears on the navi screen: "Full engine power no longer available. Possible to continue journey. Drive moderately. Have the problem checked by the nearest BMW service."

Oh well, so much for the confidence in the factory software. We'll have to wait another month to see if they are finally able to improve the stock laptimes after all the performance bells and whistles thay have added to date (suspension, wheels, software/hardware).