bad knocking/vibrating from pas rear wheel area

[Bund]

Morning,

First track day in the csl - first problem in the csl

I was at Silverstone last night and after about 2 hrs i noticed a vibrating coming from the passenger side rear wheel area. It wasnt that bad under heavy braking or accelerating. It was terrible when not on the power but i did get it home.

I am clueless when it comes to the working of cars, if this is a known problem am i best to upgrade to parts that are not bmw and who is best to do it? Im in sw london.

thanks

[trawler]

No idea, but try BM motorsport or Thorney.

[Bund]

The rear wheel was loose and the front wheel had a bolt missing. Looks like someone was after my wheels!

[houlbt]

If You are in SW London... Bexley Motorsport would be a conveniant port of call for expertise with these cars. www.bmsport.com

That aside are you sure someone was after your wheels? I only ask as you mentioned Silverstone in the same sentence. Could it be that your wheels just weren't torqued properly? Even more possible if you are new to the car and maybe the wheels have just been refurbished by the previous owner/dealer - golden rule on freshly painted wheels is to check the torques after a brief heat cycle as they do come loose.

Good luck with the car...

[Bund]

Cheers Houblt,

I hadnt thought of that, the car had come back from Murkets 3 weeks ago after some warranty work. The wheels wasnt refurbed at the time but i would have thought they took them off? The reason i thought someone had been after them was because of one of the bolts missing in front wheel and the back being loose. When i think about it though, there are 2 sets of locking nuts on the wheels so its pretty obvious your not getting them off. Unless it was sabotage? My girl friend said it wasnt her and she was top of the list of who it could be's! Iv lurned my lesson, ill be checking all nuts before next track day. I think i was pretty lucky after learning about the bolts.

[nickbell3]

Simpson Motorsport take care of my car. Speak to Anthony of Julian

[RatBoy M3CS]

Glad to hear you got your loose wheel back on again..
Let me know if your doing another day / evening at Slitherstone.. i'm usually up there on the goldtrack events, we may be able to swap notes etc.. mines not too bad round there now after a bit of work, and I want to see if I can run with a CSL..!

[Bund]

RatBoy M3CS said:

Glad to hear you got your loose wheel back on again..
Let me know if your doing another day / evening at Slitherstone.. i'm usually up there on the goldtrack events, we may be able to swap notes etc.. mines not too bad round there now after a bit of work, and I want to see if I can run with a CSL..!

Im sure your do more than keep up, mines stock apart from the Ap's. I think the car will perform a lot better just with cups or 888's. Is it right you need to run neg camber with cups and how different will the car feel for normal use with neg camber?

[RatBoy M3CS]

Hi there, did you track yours before or after putting the AP's..? what do you think of the difference ..?

You can run cups on it no problem with stock suspension, they were built that way, but what you will find is with the understeer, you will destroy your outer tyre edges.. a pair of fronts will last about 3 hours..!
I have done a fair bit of trial and error research on mine on the track now and its a huge improvement.. I'm happy to share notes if your interested..

I'm on cups next time out too, .. 888's are not available yet in a rear fitment.. but it is on the way soon..

[Bund]

Iv had the car 3 weeks so dont have many notes to share, sorry.

I can say iv had RS29's put on the front but havent tracked or bedded them in yet. Not sure what came off but they were good so i expect these to be even better.

I think im going to go down the neg camber route once i change the tyres, will i notice a difference in day to day driving? Do you mind saying where you got the cups and how much i should be paying?

[d8ean]

B,

try these guys
http://www.elitedirect.com/
talk to barry

[Bund]

Cheers dean, ill give the a shout.

[RatBoy M3CS]

Hi,

For all round steering improvements more negative on the front feels so much better, there is a trade off on tyre life but the adjustable turret tops allow you to set it to -1.25 and -2.5 for the track, and its easy to re-set it all after your track day, on track you will sh*g your fronts in a matter of 2 or 3 hours on stock settings..

Try Thorney Motorsport in Milton Keynes, if its your area, he set mine up and knows his stuff.. adjustable dampers are great for track work once you get the hang of them.. if you go for turret tops, consider doing the dampers at the same time while its in bits..save you £££'s on the labour..!

[Bund]

Not knowing about cars, what will the adjustable dampers be doing to help? Stiffen the car? How do you adjust them?

[madou]

Bund said:

Not knowing about cars, what will the adjustable dampers be doing to help? Stiffen the car? How do you adjust them?

Depending on which kit you select

1. Variable ride height
2. Spring rate ( selectable spring )
3. Compression adjustment ( single or low and high speed )
4. Rebound adjustment
5. More scope to adjust the static geometry ( camber, toe, castor )

Access to adjustments depends on which kit you pick. Top or remote mounted is convenient

Have a look at KW v3 from Thorney and Intrax from Simpsons

Some question if you should run coilover at the rear without at roll cage. Ask about service intervals and help with setup. Keep in mind a good track setup will be compromised for the road, switching all of the above variables from track setup to road setup is time consuming

If you want to know more about the origins of track car setup, read The Unfair Advantage