Too low!

[TJ7]

I purchased some lowering springs for my Z4 3.0i SE roadster as the stock (non-sport) springs were too soft for the track and the car sat a bit too high (the arch gaps were too much for a car like this). The springs are rated at 30mm, which was the only size available from 4 different manufacturers.

The little roadster now handles a lot better! However.....it now sits lower than anticipated, resulting in the front wheels hitting the inside the arches when going over the smallest of bumps and making a lot of speed bumps unbearable.

Has anybody else had this experience or any ideas on how to simply rectify without having to change everything again?

One idea I had was to change the spring pads to thicker ones, which will add approx 10mm.

 

[Nodzed]

Are your shocks good?

 

[TJ7]

Yes, I had to get new shocks only last year shortly after collecting the Z4 and the day before a track day (which is why I haven't done coilovers). But the lowering springs were approved with standard shocks.

 

[DavidM]

Some photos would be useful.

 

[TJ7]

I'll grab some photos of how it sits now when next see the car as it's kept elsewhere (not enough parking at home for all the toys ).

But here are some with the stock springs (check that lean on the track).

 

[peteslag]

The best track day handling mod for my old Z4 3.0 was a H&R anti roll bar kit. From memory, the 3.0 SE has sport springs as standard. Check out my progress thread, there is a picture my my car hard cornering with standard SE springs and an anti roll bar kit.

What size rims/tyres do you have?

 

[t-tony]

My old 3.0i came on Sport Suspension, but I fitted Eibach Pro springs and it was awesome.

Tony.

 

[TJ7]

They are CSL style aftermarket rims.
Tyre sizes on car are:
Front: 225 40 18
Rear: 255 25 18

 

[NeilH]

Is that the Blyton track? If so im looking go there with my z3 next year all being well. Might need upgrade brakes first though not sure how well standard will do on a track.

 

[TJ7]

Is that the Blyton track? If so im looking go there with my z3 next year all being well. Might need upgrade brakes first though not sure how well standard will do on a track.

That was Bedford Autodrome. You could start by getting a good set of sports brake pads and see how you get on. I have now upgraded the brakes on my Z4, but have yet to test them on track until the above issue is sorted.

 

[peteslag]

They are CSL style aftermarket rims.
Tyre sizes on car are:
Front: 225 40 18
Rear: 255 25 18

Do you know the offsets? It is normally stamped on the inside of the rim.

 

[peteslag]

Is that the Blyton track? If so im looking go there with my z3 next year all being well. Might need upgrade brakes first though not sure how well standard will do on a track.

I used orange stuff pads with standard calipers and rbf600 fluid. I never had brake fade with this set up.