Wrong Bilsteins for E46 330i?

[Jimmy46 2]

Hi all,

Just purchased new front Bilstein B4's for 2002 NZ new 330i E46.  I purchased these from Demon Tweeks UK:

for vehicles with 'standard suspension' (not sports suspension).  I've installed the first one and the car now sits much higher the previously by about 30mm.  The shaft length is considerable longer on the Bilstein than the old Sachs.  Have I bought the wrong shocks?  Should I have bought:

I don't have option S226A listed when I do a Vin decode (NH45575).  The OEM shocks are Sachs 6Z Sports - were the NZ new 330i's fitted with a different 'sports' suspension at the time?

Thanks

 

[NZ00Z3 187]

Are the Sachs the original struts?  

Was the car lowered at some stage by a previous owner?

Looks to me that you have purchased the right struts for a standard model 330i.  I'ld check the part number on the springs to see if they are original and their spec.

[Jimmy46 2]

Yeah I'm pretty sure they are original as the number shown matches on RealOEM below:

 

No signs of lowering by any previous owner.  I'll do more digging on the original Sachs but I can't see these Bilsteins settling with the original springs by 30mm.

 

[Eagle 1662]

You always going to get some lift but 30mm does sound too much if the install is correct.

Maybe some one swapped or spec'd sport suspension after the build date. Did the car sit lower than a std E46, have you measured the swaybars diameters? 

[NZ00Z3 187]

Did you measure the height by just dropping the car back down onto the ground?  You usually have to roll the car back about a car length to let the suspension settle out once off the jack/axle stands

[Jimmy46 2]

Yeah I measured after a short drive.  I'll get a measure on the sway bars but I'm 99% sure they are stock at 23.5mm.  It did seem to sit lower than stock using the 'eyeometer' against other E46 sedans.  I'll do a google and see what that throws up.

Can't get over the difference here though -

Now I'm curious about the springs and if they are a stock 'sport' springs - I'll investigate the coloured banding

 

[zero 1162]

The coloured banding unfortunately doesn't give information on what springs they are - the banding was used in the production line to make sure the correct springs went on the correct car.

[zero 1162]

It also doesnt look like the old shock is completely open - it looks partially compressed.

[NZ00Z3 187]

The original struts may have a spring on the end of the rod, where as the Bil's don't.  I know from fitting new struts to Z3's that the new struts look too short until you fit them due to the spring.

[E30 325i Rag-Top 2956]

Strange that changing the shock has affected the ride height that much. The spring is the predominant factor for the ride height, the shock is there to damp down the oscillations in the spring.

If the “neutral” position of the shock is a different point it could make a bit of a change to the ride height, but 30mm is a big number.

Has everything settled and seated fully when the car has sat back on the ground? Might settle a bit more as you drive it around, but probs not by 30mm.

[gjm 3258]

Springs change ride height, not shocks.

Shorter shocks are often required when significantly shorter springs are used. Swapping springs for shorter ones (or cutting existing springs) is a common path to lower ride height. The shock is often overlooked. This leads to compromised function - the shock is already partly compressed before it is asked to do any work. If your car had shorter springs fitted with a stock shock, it may be possible that as it has worn out, it has remained at it's enforced shorter length.

If you're fitting the new shocks with the original springs then - theoretically, and all else being equal - the height should be the same. The part number of the new shocks is correct for your car; the part number on the old shock is also correct, although I'm slightly surprised to find that shock is used on seemingly all E46 models regardless of engine (4/6 cylinder, petrol/diesel).

I agree with Nathan ( @zero ) that the original shock doesn't look to be fully extended. I don't think they  (the original shocks) are readily rebuildable so it seems unlikely it has been shortened, although that may be a possibility. See if you are able to further extend the shock?

[M3AN 4016]

My 328 certainly rides higher now that I've installed new shocks @gjm - even after 50 km's it hasn't settled. It's not because the shock is lifting the car it's because stuff takes surprisingly long to settle. Same happened on my M3.

Although I'd say closer to 15mm than 30mm.

I'd say to the OP that some lift is expected, only worry after about 100 km's and yes, the B4's are OEM height, that OEM shock isn't fully extended, it can't be, the spring wouldn't fit.

Edited October 12, 2019 by M3AN

[Eagle 1662]

As above i think its all you can really do at this point if you are sure your install is correct, can't imagine it would be worth changing out things again due to cost and time?. I agree strut\shocks themselves don't affect the height to any real degree in this instance but ive always got slight lift from replacing many worn OE Sachs with new aftermarket units and associated strut\shock hardware, there's certainly a few small hardware and install variables that could combine can change things compared to old setup. It really doesn't much force to transfer some load off a car spring to raise the height by a little.

[Jimmy46 2]

Thanks all for the feedback on this. Gives me confidence that I haven’t got the wrong parts.  @Eagle correct I don’t want to have to swap out the B4s for another part/variant if I don’t have to.

I’ll look to double check my install to see if something isn’t set right. 

[Jimmy46 2]

I rechecked my install and found the shock wasn't seated down in the clamp as far as it could go.  The image below shows a witness line on the shock of where it sat previously.  I've gained a further 5mm + of drop.  We'll see how things settle out from here.

(Re the old Sachs shock, buggered if I can extend it out further than where it currently is.  It still compresses and returns back fine but only to the point shown in the photo above)

 

[M3AN 4016]

Holy crap, is the shock just held in by that clamp? ? How the f**k does that work? ?

Edited October 14, 2019 by M3AN