Stiff Suspension

[Kerry]

I'm doing a little planning for my '88 325is. It's not a daily driver, I will be turning it into a auto-x/track day car and ripping the interior, etc. out. So I'm wondering if anyone has experience with a good stiff performance suspension. Who sells the most competitive product for an e30? Are there any coil-over kits stiff enough? I need something fully adjustable - the lot we autocross on is nice and smooth so I could run a pretty stiff suspension, but the track isn't as smooth.

[scobib]

Talking with all of my club racing buds and competitive autocrossers, most are running a full Ground Control setup with either Koni or Advance Design struts... Don't know about the spring rates, but I do know that most are running much stiffer rears. If you go this route, the GC guys can definitely hook you up...

A much more expensive, but elegant, solution are Motons with custom springs - Turner carries them... But they'll be mucho expensivo...

[Bavarian3]

The advance design shocks/struts are nice but beforwarned.... they are much easier to wear out than motons or penskie.....

Also how much money/time/effort do you want to be invovled in this equation?

The best 'bang for the buck' would be the TMS J-Stock (non-coilover) system..though some say the rear springs are too stiff....

If the track isn't super smooth....you don't want 'stiff' suspension...

BTW: How much track experience do you have? Do you know your car? I am asking this because you might want to learn the car you have stock and then slowly change things, instead of jumping right into a suspension setup...

[Kerry]

If the track isn't super smooth....you don't want 'stiff' suspension...

As stated above - That's why I want an adjustable suspension.

BTW: How much track experience do you have? Do you know your car?

Yes I know my car - 3 years of autocross, some track time mixed in there, karting, etc. I'm a novice to a stripped down car - not performance driving.

Anyone have experience with a set of adjustable sway bars?

[Skafrog]

if you are serious, get Ground-Control coil-overs.
Call them, and tell them what your plans are for the car. They are very knowledgeable, and will give you the correct rates.
You can't go wrong with Koni's, but Advance Designs are much better if you can swing the money.
As far as swaybars go, the best setup is not to run a rear bar, and find yourself a good front bar. I personally use a cabrio front bar with m3 links (the ones that go to the strut), and the setup is working out great for me.
Your springs should be used to control body roll, not your swaybars.
It can't hurt to call GC.
Also, if you are serious about a "track" car, it would be good to upgrade the other bushings you have (subframe, trailing arm, CAB's), and check your wheel bearings.
As far as camber plates go, you will want to get the Ground-Control or Ireland Engineering camber plates. Both of these products are amazing. I have first hand experience with the Ground-Control plates, and many others on this board have run the IE plates.

[e9nine]

As far as swaybars go, the best setup is not to run a rear bar, and find yourself a good front bar.

Why do you suggest this? I am curious because when I went from the stock rear sway bar to the M3 bar on my car It smoothened the car's behavior. It seems to have aded a little oversteer making the car less prone to understeer.

Is this theoretical or practical?Would it not be base on the spring rates chosen? Just curious :D

[Kerry]

As far as swaybars go, the best setup is not to run a rear bar, and find yourself a good front bar. I personally use a cabrio front bar with m3 links (the ones that go to the strut), and the setup is working out great for me.

Really? That's interesting... were you able to eliminate a lot of the oversteer? That's one thing I like about the car over my e36 - not fast, but fun to drive. Does running without the rear bar make it feel more like an e36?

Your springs should be used to control body roll, not your swaybars.

I am aware.

Also, if you are serious about a "track" car

I won't be racing wheel to wheel but yes, I'm planning on doing track days with the car.

As far as camber plates go, you will want to get the Ground-Control or Ireland Engineering camber plates. Both of these products are amazing. I have first hand experience with the Ground-Control plates, and many others on this board have run the IE plates.

Thanks for the info!

[Kerry]

Also how much money/time/effort do you want to be invovled in this equation?

It's a long term project. Money isn't a huge issue. It's a project car that I want to get done right. So I'm gathering information. The car is in medeocre condition, a little rust, rear shocks gone, engine oil leak but still running strong, interior needs some TLC. I plan to complete the project over the next five years and autocross/track it as I make changes.

[Kerry]

As far as swaybars go, the best setup is not to run a rear bar, and find yourself a good front bar.

Why do you suggest this? I am curious because when I went from the stock rear sway bar to the M3 bar on my car It smoothened the car's behavior. It seems to have aded a little oversteer making the car less prone to understeer.

In stock form I have found that e30's aren't really very prone to understeer. And any understeer they do have is eaily corrected by adjusting your driving a bit. But they oversteer like crazy, lots of fun, but slow. Eliminating the oversteer would make it easier to carry speed out of the turn. e36's are generally faster because the rear is much more stable.

Has anyone here ever really had a problem with understeer in an e30?

[Skafrog]

if you are running springs that you can't adjust the rates, I imagine some people are.
That's the beauty of GC's. I let them know 3 things:
A) What I was doing with my car (I am street/tracking it, but I dont mind suffering a bad back for lower lap times)
B) My weight (2600 wet w/o driver)
C) My swaybar situation (cabrio front with m3 links, no rear)

After listening, Jay sent me 475 fronts, and 5" 625 rear rates. The car handles like it is on rails.
Also, since none of us really have much of an LSD anymore, disconnecting the rear bar helps with the traction and wheel spin.

Since you are tracking the car, I will suggest stiffer rates. Most e30 race cars have a little stiffer setup, and combine the rates with Advance Design struts, or Koni Doubles.
Ground-Control offers a pimpy set of top-adjust Koni's that you can get them to valve to the rates you decide on. This is the way to go.

[Bavarian3]

"As stated above - That's why I want an adjustable suspension."

Just to throw it out there, adjustable suspension doesn't mean coil-overs.....

Just because one has coil-overs and one set of springs, really you can only 'adjust' ride height.... which is good but unless you have other variables that help tune camber,caster,toe, other small (but worthy) adjustments....

Obviously there is a lot of tuning you can do with the suspension.... Most 'racers' don't recommend coil-overs for a double use car, IE: daily driver/track rat....

Again advance design shocks won't be good on the street (driving to and from the track)...

In regards to running no rear sway bar... you would have to run stiff (high spring rates) *probably higher than Skafrog's* to really take advantage of no rear bar....

I am running (for example) TMS J-Stock springs/revalved Bilsteins with the BIG IE bars on our Henna track car. There is no understeer and a bit of oversteer. The car is on rails, but everyone has their own term 'on rails'..

In general you don't want a car to oversteer or understeer, but to be neutral. Easy to correct either way....

Every E30 driver has their own setup and recommendations..... but I do agree with Skafrog that you want to fresh up the bushings, get some crash M3 front strut mounts, clean the rust up.....

[Kerry]

Just to throw it out there, adjustable suspension doesn't mean coil-overs.....

Right, when I said adjustable I was actually mostly referring to an adjustable set of shocks/struts and camber plates. And I'd like some coil overs as for the first while I will need to drive it to events.

Most racers don't like them because a) they're more expensive - and b) can be a pain in the ass to adjust. I know a couple people that have had coil-overs seize on them - they fixed them, but it wasn't fun.

[Kerry]

Thanks for the info guys - I apreciate it!

[Skafrog]

In regards to running no rear sway bar... you would have to run stiff (high spring rates) *probably higher than Skafrog's* to really take advantage of no rear bar....

I agree, but I am running without one to prevent wheel spin.
The point of getting "coil-overs" is that you can tune the car. It is now ~60 dollars per spring, as opposed to being stuck with a single spring rate (Turner J-Stocks, etc) and then having to correct with sways. Also, you can corner-balance your car with coil-overs if you feel like it.

However, I would have to say: Listen to Bavarian3, he knows what he is talking about.

[trent]

In regards to running no rear sway bar... you would have to run stiff (high spring rates) *probably higher than Skafrog's* to really take advantage of no rear bar....

I completely disagree. I am running no rear bar with relatively low rates. If the rear of the car is tuned to the front it isn't necessary. Levels of grip will still be there. I think there are way too many people setting cars up too stiff thinking it is the bomb.