The suspension setup/ride height thread

[Wiglaf]

ok so i'm not happy with the cosmo coilovers, too stiff for the streets around here. and the rear adjusters are topped out but i still have too much neg camber. Winter is coming and I'll have to be driving this thing so a little extra height will be good.
The rates on cosmos are 450lb/in 6" front, 560lb/in 5" rear.
seeing as the stock 325is rates are 118/265 that's more like 1:2 ratio. So I have an idea..

Move the front spring to the rear. That gives me an extra inch and lowers the rate a little bit. Then buy a 200# 7" spring for the front.
This should give me softer, taller ride and I only have to buy 1pr of springs.
and 200/450 is actually really close to the 118/265 ratio.
What do you guys think?

[JRKOUPE]

your numbers are a bit confusing.....

your current rates are good imo..its a very common street set up...maybe its the shocks?...

a 1 : 2 ratio is not correct.

HR race....GC's suggesdted rates...etc etc.. are not 1 : 2.....


use 450/600 as a PROPER ratio.....and try like a 300 oR 350 FRT.....U CAN Figure out the rear


my Hr race are like 350 ish and 550 ish rear iirc...

[Wiglaf]

your numbers are a bit confusing.....

your current rates are good imo..its a very common street set up...maybe its the shocks?...

a 1 : 2 ratio is not correct.

HR race....GC's suggesdted rates...etc etc.. are not 1 : 2.....


use 450/600 as a PROPER ratio.....and try like a 300 oR 350 FRT.....U CAN Figure out the rear


my Hr race are like 350 ish and 550 ish rear iirc...

Not to argue but I want to cut WAY back on how stiff the ride is. The roads around here kind of suck. Potholes, heaves in the asphalt that resemble speed bumps, etc. the 450/560 linear rate spring is beating the shit out of me and the car.

I should mention it's a convertible and the rear springs are in the stock location, they are not true coilovers back there. I'm looking at this chart:

Let's start with spring rates:

Spring---------------------Front(lb/in.)-------------Rear(lb/in.)

Stock 325i-----------------------106------------------------245
Stock 325is----------------------118------------------------265
Stock 325ix----------------------106------------------------308
Stock M3-------------------------114------------------------314
Stock M3--------------------------140------------------------250
Dinan Sport-----------------------172------------------------300
H&R OE Sport---------------------180------------------------380
H&R Sport-------------------------180------------------------380
H&R Sport (29664)---------------200------------------------285
H&R Race-------------------------315------------------------ 570
H&R Coilovers***----------------340------------------------380
Eibach Pro-Kit--------------------102-------------------------277
Eibach Race----------------------160-------------------------445
IE SIII----------------------------315-------------------------570
Koni Coilovers-------------------342-------------------------407
Cosmo Coilovers----------------450-------------------------560
Tokico----------------------------165-------------------------265
TMS J-Stock**-------------------680------------------------1026
Alpina(est.)---------------------~200-----------------------~350
FK 60/60 cup kit-----------------379--------------------------379
Vogtland Standard***--------115/197-----------------------360
Vogtland CS***---------------137/200-----------------------400
Vogtland--------------------------225--------------------------360

Most of the lighter springs there are in the 1.8~2.8x range with stock being 2.2~2.7x and it doesn't close in to the 1.5x zone until we are getting into rates much higher than I want to be in.

If I buy a coilover spring it will still be linear rate but going from 450/560 to 200/450.

Also I've tried vogtland, they felt ok but were seriously way too low on ride height and the rear would scrape all the time. The rear felt really dippy compared to the front, so I think keeping that ratio above 1.6 is a good idea.

Is the HR race a progressive rate spring?

[JRKOUPE]

I hear ya...

based on your goals..forget about Hr race..not for you.

I run Dinan on a z3 coupe..like them alot.

this is very subjective you know...right?..depends on shock too!


Id say mimick Dinans rate..his stuff usually works..or even Alpina......they usually do it right.

[bacton]

Hey R3v members I need some help dialing in my coilovers. I purchased and installed Megan coils (essentially BC'S) on my 88 325 and seem to be having extreme wear on the inside edge of my rear tires. I've done some reading and this seems to be a common occurrence on lowered e30's but for instance in the images above, these cars don't seem to have nearly as much of a cambered rear end. I would like to increase contact patch on my tires. Any suggestions? Fyi- Havn't had the extra cash for a proper alignment, although it tracks straight.

[Wiglaf]

welcome to r3v. read up on some threads around here, nearly anything you need to know is already here.

anyways the rear camber goes highly negative as you lower the car and can't be adjusted unless you do some mods. the only thing to do is raise the rear ride height and make sure your bushings aren't trash.

mods to consider-
poly bushings all around
eccentric bushings (not popular b/c they don't do enough and go out of adjustment)
weld-on adjustment tabs- more popular but a lot of work
subframe raising bushings- helps a little bit, easy to do in addition to the others. it all adds up.

[jrockbk]

Loving my ground control setup but does anyone else hear noises from the springs like binding when they turn at slow speeds?

[RedReplicant]

Ground Control 440lb/650lb
SW22 MR2 Rear KYB AGX front
Camaro KYB Gas-A-Just rear
AKG Offset FCABs
BMW Style 5 16x8 +23 w/ 18mm 42Draft adapters effectively 16x8 +5
205/45/16

[RVA_Zinno]

Hey guys, this might be the wrong thread for a question but I'm looking for a good pair of springs that will bring my car down a bit lower than the stock height. Low enough to lessen body roll but still high enough where as to not scrape on anything.

[RedReplicant]

Well, went GC Race plates and the difference between the stock strut mount and Race plates is right about an inch.

[dirtbag30]

Well, went GC Race plates and the difference between the stock strut mount and Race plates is right about an inch.

looks so much better, can definitely tell the difference.

[RedReplicant]

Thank you :) Definitely looks much better but goddamn, hitting the skid plate hard a few times a day.

[JRKOUPE]

Thank you :) Definitely looks much better but goddamn, hitting the skid plate hard a few times a day.

yes..it looks great..but sheesh its lo for street.


can u tell me how your rates feel on the street?..is it really harsh?..beating you/car up?...

I realize its subjective...just curious.

car looks really good.

[RedReplicant]

yes..it looks great..but sheesh its lo for street.


can u tell me how your rates feel on the street?..is it really harsh?..beating you/car up?...

I realize its subjective...just curious.

car looks really good.

It's 440/650 and feels fine on the street, to me. Little bit of bounce over wavvy sections of road, but that comes down to me being a cheap-ass with KYB AGXes.

[JRKOUPE]

Red:
u r correct..prolly the shocks


to others:
I was wondering if folks could chime in on what length the frt and rr springs are.....and where you are in terms of ride ht...can it go much lower/higher? A few have included this info...cool.


I have 6" frt and 5 " rr about to go on....