Early model E30 lowest lowering rear springs???

[Northern]

Can confirm 1" shortening plus spacer works well.
iX Koni Sport works well for 450lb/in spring up front.
If using a higher front spring rate, you might consider Koni 8610-1437-RACE over the iX. Dimensions are nearly identical.

[iXguido]

thank you for the heads up i appreciate it.

Honestly with all this trouble to mismatch the springs with the right struts/shocks, cutting not cutting the strut housing and the list goes on...i feel like im leaning towards a full set of coilovers now such as Megan racing or BC racing. It's Soda Not Pop has a point

No worries. I think you should have enough info from this thread to decide what is best for you. If you're just trying to get the rear height figured out, the GC kit is probably your best bet. If you're still looking at the full front and rear setup, then coilovers are the easy choice if you have the money.

Normally housings are cut 1 inch and damper sleeved up 1 inch.

I had a spacer under the damper so that it was right up to the retaining nut. 1 inch would probably be just about perfect to retain max travel and my desired ride height.

[moatilliatta]

I wouldn't focus on tucking. Id just try and keep your front control arms parallel to the ground and set the back about the same fender gap. It'll ride and handle better. FK stance.

[moatilliatta]

Normally housings are cut 1 inch and damper sleeved up 1 inch.

[DAN-E30]

So I double checked my rear springs because I wasn't sure I had 4inch rears. Turns out mine are 5.5inch rear springs. I took a pic of the rear spring and where my adjuster is set. Looks like I could drop maybe .5inch at the max in the rear with the 5.5inch springs.





Regarding the fronts, I'd be cautious shortening the struts right away. I am using ix Konis in the front because I wanted to lower the car and retain maximum suspension travel. I shortened the struts 2inch and when I put everything together, the car was slammed with the adjusters all the way at the top. The pic below is as high as the car would go in the front with the struts 2inch shorter and the adjusters at max height. I ended up having to cut the struts again and weld back in the 2inch piece just to get back some height. At first I thought I could just buy longer springs, but the Konis were fully extended with the 6inch springs so that did not work.

Also you are going to want to get a skid plate in the front to protect your oilpan

thank you for the heads up i appreciate it.

Honestly with all this trouble to mismatch the springs with the right struts/shocks, cutting not cutting the strut housing and the list goes on...i feel like im leaning towards a full set of coilovers now such as Megan racing or BC racing. It's Soda Not Pop has a point

[iXguido]

So I double checked my rear springs because I wasn't sure I had 4inch rears. Turns out mine are 5.5inch rear springs. I took a pic of the rear spring and where my adjuster is set. Looks like I could drop maybe .5inch at the max in the rear with the 5.5inch springs.





Regarding the fronts, I'd be cautious shortening the struts right away. I am using ix Konis in the front because I wanted to lower the car and retain maximum suspension travel. I shortened the struts 2inch and when I put everything together, the car was slammed with the adjusters all the way at the top. The pic below is as high as the car would go in the front with the struts 2inch shorter and the adjusters at max height. I ended up having to cut the struts again and weld back in the 2inch piece just to get back some height. At first I thought I could just buy longer springs, but the Konis were fully extended with the 6inch springs so that did not work.

Also you are going to want to get a skid plate in the front to protect your oilpan

[It's Soda Not Pop]

With all this trouble it still might be beneficial for you to save up and buy a full set of coilovers. You can have the front strut tube and knuckle welded and powder coated when you put in the order. CATuned does this service and GC.
I know money is tight at times and I can understand doing what you can with what you have. But sometimes that ends costing more. This has happened to me several times. Trying to save a dollar I end spending 5.

[WestCoastEta]

sorry i bombarded you with questions but how did you shortened the front strut housings 2'' on your car?

I paid E30SPDFRK to do it lol. But there are plenty of guides online. A little cutting & welding.

You don't need to shorten them unless you're trying to be fully slammed

[DAN-E30]

It's a long thread, but the Spec E30 board has an interesting discussion on the topic here since they are required to use Bilsteins with the Ground Control setup. Not sure if you have camber plates as well, but ditching the stock strut mount for camber plates drops the car around 1/2-inch or so due to shorter stack height.

ok i will check it out, thank you

[mtech325]

It's a long thread, but the Spec E30 board has an interesting discussion on the topic here since they are required to use Bilsteins with the Ground Control setup. Not sure if you have camber plates as well, but ditching the stock strut mount for camber plates drops the car around 1/2-inch or so due to shorter stack height.

[DAN-E30]

If you shorten the strut housings (so you can lower the ride height and retain proper shock travel), you would need shorter strut inserts, such as from a 325ix. Having pieced together suspensions versus doing it right the first time, I'd suggest getting Ground Control's complete setup with their custom valved Koni shocks/struts and having them shorten and reinforce the strut housings. That way you lower the car with the rates you want and the ride quality will still be good.

Bilsteins are good quality shocks, but in the e30 application at least, they don't seem to work as well with higher spring rates. Not sure on the newer Bilsteins, but the older ones you were able to pop the cap off the bottom to trim the bump stops for a little more travel, so could be something to consider, but I'd still pick Koni over Bilstein in this case.

So if i don't shorten the struts housings and keep my Bilsteins would i still be able to go low enough on 17s inch wheels to close the tire/fender gap and retain an acceptable shock travel? im asking because i already got my struts/shocks, Bilsteins infront and Koni's sport in the back so it would be great if i can keep them for my GC c/o conversion kit im getting

[DAN-E30]

I'm running 4" Eibachs in the rear with GC conversion kit adjusters. There's still a little room to go lower.



The rear GC perches use 2.25 ID springs.

(Front strut housings were also shortened 2")

sorry i bombarded you with questions but how did you shortened the front strut housings 2'' on your car? youtube GC conversion kit installations don't do it

and is it something necessary to do with the GC c/o conversion kit in the front to go as low as possible if i need to? i currently have Bilsteins sport in the front and like i said before Koni's in the back

[mtech325]

If you shorten the strut housings (so you can lower the ride height and retain proper shock travel), you would need shorter strut inserts, such as from a 325ix. Having pieced together suspensions versus doing it right the first time, I'd suggest getting Ground Control's complete setup with their custom valved Koni shocks/struts and having them shorten and reinforce the strut housings. That way you lower the car with the rates you want and the ride quality will still be good.

Bilsteins are good quality shocks, but in the e30 application at least, they don't seem to work as well with higher spring rates. Not sure on the newer Bilsteins, but the older ones you were able to pop the cap off the bottom to trim the bump stops for a little more travel, so could be something to consider, but I'd still pick Koni over Bilstein in this case.

[DAN-E30]

Before welding in camber / Toe adjusters get and alignment with your ride height that you want and see where you are. A lot of people just weld these things in and cant get into the range the need to. If you're going to run 4" spring in the rear, I'd consider shorten front strut housings.

I like the machined ones, if you go aftermarket RTAB, make sure the sleeve is steel and you have a good Genuine lock nut.
https://www.bimmerworld.com/Suspensi...-Z3-318ti.html

Check your front strut size before thinking they'll work. Early early cars had small front strut diameters.

ok perfect i will do my alignment before any welding in camber / Toe adjusters got it.

On the other hand do you think my Bilsteins sport would still fit if i shorten the front strut housings? i saw two youtube videos installing GC kit on e30s but i didn't see them shorting the housing. Do you have a reference for me i can read or watch?

[moatilliatta]

I just send GC an email to get all the informations i need.

Ok i understand. So i don't think i will be removing the adjusters in this case but i will definitely try the lowest setting with adjuster, i will keep a very small gap between the tire and the fender so i won't rub. Weld in camber adjusters are a pain to install? where can i get in case i have to?
keep in my mind my wheels are 17s so i won't need the same drop to close the gap as if i had 15s

Before welding in camber / Toe adjusters get and alignment with your ride height that you want and see where you are. A lot of people just weld these things in and cant get into the range the need to. If you're going to run 4" spring in the rear, I'd consider shorten front strut housings.

I like the machined ones, if you go aftermarket RTAB, make sure the sleeve is steel and you have a good Genuine lock nut.
https://www.bimmerworld.com/Suspensi...-Z3-318ti.html

Check your front strut size before thinking they'll work. Early early cars had small front strut diameters.