E30 Zone

I am fitting a bilstein streetline suspension kit to my car. The kit is suppose to lower a std 325i by 40mm. My car (325i SE) has the mtech suspension fitted. I went to fit the front shocks and springs and noticed that the new springs are 40mm shorter than the mtech ones(uncompressed) and also the diameter of the shock rod (the chrome bit) is smaller than the mtech one.

My questions are: Are the mtech struts different to the std 325 ones, ie. is the lower perch in a different place?

Also are the shock rods a different diameter between mtech and std 325?


The new shock fits in the strut housing and the black part of the shock is the right length and diameter but when I put the new spring on I don't even need to compress the spring to get the top nut on.
I was expecting that this kit would only lower the front by approx 10mm. I have fitted the rear end of this kit and it dropped it by 7mm.


I await your expert advice!

There is a thread under www.bimmersport.co.nz under the maintenence section with photos etc if this helps.

yes the tech shocks are alot thicker and a 25-30mm drop with tech springs from standered so you should be aroud 10mm lower than before
billies are going to be just as storng and stiffer to boot. The position of
everthing will be the same ur not low enough to have a camber problem.
Enjoy..

The gas charge in the Billies will tend to make the car sit slightly higher with the same springs as opposed std shocks.

Thanks for the tips, I'll finish putting the car back together tonight.