How to turn my car into a corner monster?

[Jand3rson]

I want my E30 to be a corner-devouring machine, and by that, I mean I want it to handle as good as it can. But at the same time, I don't want the car to rattle apart eveytime I cross the painted lines on the road. The E30 I'm getting is already dropped on Eibach Pro-Kit springs and Bilstein Sports, but I plan to replace the Eibach's with H&R's eventually. I am also definitely going to run a Sparco strut brace up front, and a Lukas strut brace in the rear. What other things should I look into installing/upgrading on my suspension to make it handle as good as possible without destroying my ride quality?

[bimmerphile]

Suspension Techniques sways.

The difference is night-and-day when you get those licorice ropes out of there.

Also, think about your tires/wheels too. Thinner sidewall = less sidewall flex = better feel in corners.

Not directly related to your suspension, but what about an E36 M3 steering rack :idea:

Corner "devouring monster" and "not filling-remover" don't really go together unfortunately...well, unless you can get some PSS9's, but no can do on the ole '30 :(

[Jand3rson]

I guess I should modify that a little. I want my car to hanlde as well as possible without completely doing away with ride quality altogether.
I don't mind stiffness, but I don't want to lose all my fillings driving to work.

BTW, the Suspension Techniques product PDF only lists swaybars for the 84-91 318i, and the 87-92 325 cabrio. Are the 318i ones the same as for the 84-91 325i? (stupid question, I know)

[e9nine]

I know this is corny as hell but ...the driver!
I have seen a stock m20s and other stock or vey lightly modded cars whup serious ass cos of the driver. We all take to driving differently. Some people have modded to hell cars and can't drive them for shit. I'll be a hypocrite and admit my car is modded ahead of the driver by the way :roll:

Suspension is an intimate mod. You have to either try out some elses setup or take the leap and put your own kit together. There are TONS of options as you already know. Avg off the shelf springs and shocks and sways or COs pretty much summarize it up. Bear in mind that there are trade-offs for suspension mods. Harshness, Squeaks and/ or Squishy Mushy Slammed car that will break oil pans and destroy lips. Which do you want?

Yes ST bars from non e30 m3s are compatible across the board

[Jand3rson]

e9nine, you couldn't be more right about the driver. I plan on attending a driving school as soon as I get my license back.

I think I will definitely end up ordering the Suspension Techniques swaybar kit from Turner Motorsport for starters.

Also, would you guys reccomend using urethane bushings wherever possible, or stick with rubber? I also plan on installing Ground Control rear shock mounts and aluminum control arms.

[nando]

do you want your car totally slammed? a setup like H&R sports with bilstiens would handle very nicely and still give you decent ride quality. toss in some swaybars and you have a very capable car. maybe do some driving schools and decide if you need something stiffer.

my car seems stiff enough to me.. i think it's mostly the konis. not quite teeth rattling but with the urethane bushings it's very solid.

[modifiede30]

You won't be able to maximize cornering without good brakes. i.e. entry speeds and maximizing the straights. Don't forget about them. Also, have you thought about coilovers? Sway bars are great for reducing body roll, thereby reducing weight transfer under load, but corner load also impacts camber and toe changes from standing measurements. If you can't change camber after dropping the car, you cornering will suffer - adjustable camber plates are a must for proper suspension tuning. The coilovers will also allow you to better distribute weight at all four corners.

You might want to make some minor modifications and learn the car's abilities first, then decide what needs tuning. If you don't know what it can do before modifying it, it will be difficult to know what to change. Stock sway bars aren't that bad, except the back. Before blowing all your money on new ones, you may want to just replace the rear with an M3 bar, and buy adjustable links up front so that you can begin to tune body roll. If it already has eibach and bilsteins, you won't be maximizing the setup for a while anyway. Focus on stopping first- brakes, then tuning the suspension, and then the engine.

[EVOIIIM3]

Fist thing, plan it all as a UNIT!!!

You must upgrade all the bushings also!! It doesn't matter how stiff the shocks are if the rubber difflects and changed the caber and toe.

Setting up suspension is a science and expensive......
All new bushings
New tie rods
new control arms
Strut braces
REALY, REALLY good shocks!
Good sticky tires
camber plates and trailing arm adjustments.
Reinforce the trailing arms, in the X & Y axis.

It doesn't have to be super stiff to handle well, but there has to be a trade off some where. Notice I didn't put sway bars on there? You can tune the roll radius with springs and shocks using the stock bars, really stiff SB's just turn the independent suspension into linked suspension.

The "best" street setup is....
Coil overs (corner balance the car) pick the best spring rates.
Morton shocks
delrin bushings
alm control arms
urethane subframe bushings
either K-mac or Dinan trailing arm adjusters
Camber plates
solid RSM
some DOT-R rubber

[MattM20]

tires play a very big role in mechanical grip, don't take the cheap route on them, and deffinately try to find a way to squeeze 225's in there. then the camber plates and toe adjusters will help further maximize the grip thresholds. you also have to try to find a good balance with the shocks and springs. adjsutable shocks (koni) will really help in neutralizing your handling especially when you have the ability to adjust the camber, toe, and sways for the perfect balance. another thing to consider is the pitch angle. coilovers would be perfect for tuning the proper height of the front and rear to put the F/R weight ratio right where it needs to be instead of guessing with non adjustable springs like IE or the prokit. for instance, if your running a huge amount of power later on to the rear wheels, you would probably need more weight balance in the rear, but if the sways and strut brace tighten up the front too much then you would need to lower the front a little bit to transfer more weight to the front wheels. you'll need to spend alot of time getting the balance right, and it's alot more helpful to document the effect each mod has instead of throwing them all on at once

[Jand3rson]

That's some great advice, Mike. I will definitely take all of that into consideration. I may do coilovers later, but right now they are just going to be to expensive.

I didn't think about new tie rods, I wil have to add those to the list.

modifiede30: Brakes are definitely on the list as well. Brembo rotors are already on the car, as are new pads (can't remember what kind). I also plan on upgrading to stainless steel brake lines and possibly having the calipers rebuilt, depending on their condition.

nando: I don't neccesarily want the car SLAMMED, but I do want it to have a nice looking ride height. It already has a good looking stance due to the Eibachs, but it may be a little too low. I plan on switching over to H&R springs, which I don't think are quite as low as the Eibachs. But I think I've picked on major thing out of all this, drive the car first and get a feel for the suspension, and then decide what needs to be done.

[Jand3rson]

Is there a way to get H&R cup kit springs without ordering the whole kit? Will the work with Bilstein sports?

After talking to Jordan, I'm just going to drive the car as is for a while, and decide what is needed from there. But I will for sure at least be running strut braces front and rear.

[darien28]

best to just get the rear subframe modified for adjustable camber instead of using the offset trailing arm bushings. it'll be much easier to adjust in the future and cost about the same.

as for the rear sways, if you upgrade, you will most definetly want to reinforce the rear sway mounting points, which is easily done when the rear subfram is removed for the adjustable camber modification.

other than that... run the widest track you can on the wheels, widest and lowest profile tires, lower the center of gravity of the car, lighten the car, and proper suspension.... I suggest IE stage 3 springs wiht some good adjustable shocks like konis. the IE3 springs aren't too harsh for the road and are reasonably priced.

other than that... it's all about the driver, I'd rather spend the $500 you would spend on sways and strut ties for a weekend of track school... you'll be a MUCH MUCH better driver.

[Old'n'Slow]

My jackass, old fart opinion!!!

With all the emphasis on lower and stiffer, don't forget that those things equal less compliant.

What I mean is, on a skidpad, or perfectly smooth roads, lower and stiffer works. But we don't all drive on billiard tables! If you are super low, and have not perfected the shock valving, bumpy corners may "jack" the shocks down, you run out of travel, then fly off the road!

I have to laugh at some the proposed mods(note: it's the IDEA of those mods, not the person suggesting them that I find amusing)...full urethane everything will make your car very annoying on long drives. Of course it depends on your tolerance, but the fact that you state you don't want the car to "rattle apart" over pavement irregularities, I cannot remotely imagine you'd be happy with a streetable race car!

OK...in the real world...remember the mid eighties Corvettes? Stiffer, lower, harder so it would corner? My car is sensibly lowered with H&R OE Sport springs and Boge Turbo shocks. Stock sways. No tie bars. 205/55/15 Dunlop SP5000 ALL SEASON tires...get the picture? Nothing super modified. I've driven my '88 ETA in the mountains with a long time friend in his 86 'Vette. As long as the corners are smooth, with no ruts, ripples or broken pavement, his car sticks better. BUT, often, the corners were pretty chewed up, and his stiff car couldn't stay hooked up. I could! Compliance can be your friend. He was amazed, sold the 'Vette and drives a '90 M3 now!

Now, having said all that, if you don't care about the noise levels in your car, or about your fiscal condition, go do all the recommended stuff. You will be the King of the Freeway Entrance Ramp. Your wallet will also be much lighter. This also enhances cornering speeds! (Sorry, I couldn't resist!)

There's no way I'd do all that to a daily driver!

BTW, as other have stated, the FIRST mod should be on yourself. A properly prepared driver will always get more out of a car than a dilatant with deep pockets. Go to a driving school. In the words of Jim Fitzgerald, my driving instructor at Road Atlanta, where I raced 240Zs in the early 80's, " Cars are seldom truly out of control. Drivers often are!"

[nando]

urethane really is not that bad. My car is solid, not teeth rattling harsh! the bushings only keep the suspension from moving around, your shocks and springs have more to do with ride quality.. Plus urethane will last a lot longer, and if you're replacing all your bushings anyway, why bother with rubber? derlin, on the otherhand, is probably overkill for a street application.

oh, and strut braces make a huge difference.. plus they are cheap and easy to install.

[Old'n'Slow]

Hey nando,

You may be right about urethane. I was thinking about what we had in the 240Zs....it was red and hard as a rock and squeaked over bumps... bushings, mounts, links, all brick stiff!

Gives me a headache thinking about turn 3.....bump...ba bump...BLAM...ba bump...such a racket! ;)