Custom DIY Suspensions. WHo has done it and how?

[mpowerful]

So I went back about 10 pages in this subforum reading the very limited number of posts that were solely about suspension. I am familiar with the normal stuff. SE30, GC, TCkline, etc. I did see some people post some reference to building their own and I am just curious which ones of you are out there running 1 off suspension setups and how/what did you use? I am toying with suspension ideas for my car.

[TobyB]

Well, for the 2002 I started messing around with a new rear subframe and trailing arms to
reduce camber gain with wheel travel, but didn't get very far... built a Pro3 car instead!

Is that the sort of thing you mean? Or are you talking about spring/shock choices?

t

[mpowerful]

^really anything mild to wild. But yeah more interested in out of the ordinary spring/shock/coilover combos and builds

[petrolhead]

What car do you have, and what do you hope to achieve? Or to put it another way. What sort of driving, what's the current setup, what are you unhappy about in it's handling?
There's all sorts of tweaks you can do to an E30's suspension that doesn't neccessarily cost an arm and a leg.

What TobyB described above has to do with suspension geometry, and that side of the puzzle shouldn't be ignored. Geometry stuff is what gives the car it's basic handling traits (along with other things ofcourse but..)

-Jarno

[petrolhead]

Well, for the 2002 I started messing around with a new rear subframe and trailing arms to
reduce camber gain with wheel travel, but didn't get very far... built a Pro3 car instead!

Is that the sort of thing you mean? Or are you talking about spring/shock choices?

t

Decrease rear subframe movement and rotation. Set the trailing arms so that the line through the linkages is level, not angled outward like it it stock. Reduce trailing arm sweep angle. Reduce trailing arm bushing compliance. I've no idea how to achieve this except steel joints. Last resort, reduce wheel travel.

[TobyB]

In this case, change trailing arm pivot angle by about half.

But it snowballed into 'complete custom trailing arm fabrication'
and we have a lot shorter winters than you guys do, so the parts
are in a box at the bottom of a very tall pile waiting for an unusually
ugly winter, or until I retire...

t

[petrolhead]

I've got a spare rear axle carrier and arms waiting for inspiration/ an idle winter night :).
Bad thing is, DIY-suspension arms could never be street legal around here, no matter how well made.

[Beej '86 325es]

On the rear of my car, I wasn't happy with the GC setup that used the 2.25" springs.

I switched to a 2.5" OD x 6" long spring on an H&R adjuster, with a TC Kline short-body Koni shock. I've run this setup for years.

[djjerme]

Toby, have you ever seen the pic series someone did on a complete REAL DTM E30 suspension? Had some great insight in to all the customization they did to front and rear subframe(s) to get adjust-ability and durability. I will try and find the link again..

As for OP - I built my front coilovers for my own PRO3 car. They have gone through a few iterations, but the basics:

-Stock strut housings sectioned and rewelded with a couple inches taken out of them.
-Stock spring perches trimed off and GE coilover adjustable sleeves added (had to reweld on perches for them to sit on, and a little JBweld to keep them from spinning on the strut housing.)
-Koni single adjustables for a G60 Corrado VW and a stack of washers in the bottom to bring them up to height (so they are tensioned against the glan nut on the top.
-I forget the springs I have in front right now, but have experimented with a few over the past few years (650# maybe?)
-Camber plates started life as some old design GC maybe? Not sure, but I got them second hand, then the center bearing plate cracked and I replaced it with a plate from a set of E36 Camber plates (not sure where I got those..) Then I welded bigger bolts to the attachment points to keep from stripping them (don't ask..)
-SE30 sway bar in front for now, traded my big bar to someone else because I had this crazy idea to run SE30 in the PNW (yeah that was a misstep..)

The setup has run good for me, and is a lot more capable then my ability and it's not whats slowing the car down right now (about 2 sec off lead pace because the motor has a bad overheating problem and is waaaay down on power this year.) If I did again, I probably wouldn't cut as much out of the strut housing, it is possible to be TOO LOW!

[TobyB]

street legal around here,

No- one looks here in Warshington state... I don't even freak out
when I lose a headlight, taillight, etc. Wild Wild West, baby!

Gustave's site had a great bunch of pix, and there have been more that popped
up here not too long ago Really cool stuff! How to make an oxcart handle AND be adjustable
for roll center...

t

[e30_302]

Only "custom" thing I've done are roll center correctors. That page showing all the DTM goodness makes me drool.

[mpowerful]

^someone find me a link to this dtm page stat. Hahaha. Thanks for the insights as well!

[FredK]

http://www.m3motorsport.co.nz/products/suspension-and-steering/dtm-rear-suspension

This company in NZ has pretty crazy DTM reproduction stuff.

[Panici]

Only "custom" thing I've done are roll center correctors.

Any more details on these? Did you notice an improvement?

[TobyB]

http://teslacoils.org/e30m3performance/

was what I was thinking about...
t