Hypertek

iTrader: (3)

my point was that they where not changing the design of the suspension, but where able to pull off what they could with simple bolt ons. which is pretty good imo.

Roen

iTrader: (2)

Cantilever + SLA would be a good alternative to 8

WingsofWar

see..now your just speaking in tongues...lol

NotTTT

Sooooooo you're saying that you don't like the design, that the design should be changed, that pretty purple bolt-on parts make the inferior design capable of impressive things.... Well hey, you got to reference a japanese tuner and post lots of pics. And with that, I'm out

In that case, specific to item 10 on your above list,

I think that there is little to be gained with the front subframe. It's not that heavy and serves a few purposes. The rearon the otherhand I think can be improved upon. To me, it seems very heavy and awkward. Perhaps building it out of chromoly to lightne in up a bit? Maybe just welding the mounting points needed for the suspension to the chassis and stregthening the areas surrounding the mouting points? I think there is a little to be gained it weight doing it that way, but not so much more over stock in terms of adjustment.

The rear control arms can be lightened slightly, but would be difficult to reproduce.

As far as the front, there are hotrod kits out there that could be adapted to the FC. All you would need would be a welder, a plasma cutter, and a dream.

Roen

iTrader: (2)

Why not? Inboard shocks are independent of control arm design, right?

NotTTT

Yes, but the way I'm picturing it, the entire stock strut tower and probably 8" fore and aft would need to be cut out in order for the new suspension to be able to fit.

jdmsuper7

iTrader: (1)

You'd probably need to re-arrange the turbo piping/position on the front to do this...

If you wanted to do an excessive amount of work to the suspension for no reason...
You could lay a small damper/spring setup down along the front frame rails in the engine bay and use a push rod mounted to the upper part of the stock hub to actuate it. With all the area where the McStrut used to be freed up, it wouldn't be nearly as hard to mount an upper arm, again using the upper hub mount, even if you ended up using a honda-like design with a heavily bowed upper arm that mounts where the original upper spring perch was. It would look cool, but wouldn't be coupled, so the true benefits of a cantilevered system wouldn't really be seen. It would be a good way to waste alot of time and money.

I know I've seen a picture of a coupled rear system, with both (pushrod? actuated) dampers/coils laying in the hatch area. So this must have been done at some point, even if it was just for show. Again, lots of time and money, little gain.

ITSWILL

iTrader: (12)

does any one have any numbers for lateral Gs on stock fcs?

how about lateral gs on modified fcs? (coil overs, fancy purple things, sway bars, ect)

Now what would be a goal for an entirely redesigned suspension?

Is it worth it? (if so, to who?)

jdmsuper7

iTrader: (1)

Leteral G's are very heavily a function of tires. You would probably need something like a high speed slalom with elevation AND camber changes to really see the difference, and have all cars on equal tires.

LargeOrangeFont

iTrader: (7)

I have not removed the rear sway on my personal car yet. I plan to try it at the next track day in a couple weeks. I understand why the car would be easier/smoother to drive without it. I think benefits are really seen when using a suspension setup that has very little droop.

I think the toe links are a good idea, but paying $300 from AWR or Supernow is rediculous. I can make my own for $75-100 easily. I have heard rumors that MMR is coming out with toe links of their own. If they are under $150 they would be a very good option.

I think the roll center and K member would essentially be one and the same. A tubular chromoly K member would be great, with a coule different arm mounting locations for different ride heights. Also, a tubular rear subframe and tubular rear arms would be excellent products. The arms would be pretty tough to make and probably are not cost effective however.

DTSS is what it is. It serves its purpose when the bushings are fresh. if the bushings are shot, get rid of it.

ITSWILL

iTrader: (12)

Thats my point. ( there would be a lot of comparison and analysis to be done before you could even think of doing something like this)

You are taking an excellent handling car and wanting to completely revamp its suspension.


It seems to me that between the products out there such as coil overs purple adjusty things and R compound tires, while they may be band-aids, do get the job done.

For the effort it would take to engineer a new suspension ( which would quite possibly involve new subframes) it's just not worth it.

MaczPayne

iTrader: (5)

The "effort" varies from person to person. For someone that's very resourceful, this endeavor may not be as hard to them as it is to maybe you and I.

ITSWILL

iTrader: (12)

True, I just think it would be more time consuming than anything.

Black91n/a

Your biggest challenge in the back will be mounting the subframe for A arms, since the stock one is in entirely the wrong place.

I think you're VASTLY underestimating the subtle complexity of suspension design, there are many, many ways you could screw it up and make the car worse than stock.

I also thing you're VASTLY overestimating the advantages that A arms will give you. M3's and 911's all use struts, and they're very sucessful in racing and are very fast cars.

Your money will be MUCH better spent on wide, sticky tires and good shocks than fundamentally changing the suspension. I'd put money on that.

NotTTT

I don't think they're band-aids at all. I think those are some of the things that need to be done when modifying a car and negating all the compromises that the factory made. A second reason I don't think they are band-aids is listed and well said below

I've driven bone stock M3's and 911's. Driven them HARD and there is very little body roll at all. The big advantage to A-arm suspensions (in my eyes anyway) are when using soft springs. With A-arm suspension there is less camber change to the contact patch through the range of motion maintaining a better contact patch. Eliminate the cause of the motion (springs and shocks and to a degree sway-bars) and all of a sudden the benefit is reduced simply becuase the advatage of one is so small.

FWIW the E46 is my next car as a DD for a few reasons. 2 of them are
1) Rides so nice on the street
2) Rides so nice when driven hard

Meh, it's also personal pride, pipe dreams, or setting a goal when not fully aware of what's completely involved and sticking to it. Take my project for example. There have only been maybe 4 people who have agreed with my reasons for doing it and maybe 2 still agree that it might be worth it in the end. A very close friend of mine said to me a few days ago (after blowing one motor, buying another only to find out that it wasn't what we had hoped, and cracking my old n/a block only to find bad housings that we were hoping to use), "You just don't know when to give up, do you?" My answer was simple, "no I don't and it's a strength that alot of people don't have." With that said, if someone is stubborn enough and wants to go for it, by all means but I think it's going to be alot of trial and error, alot of cutting out of pieces that are welded in, alot of different combinations and the first few variations will probably not be as good as a "stock" FC's suspension with a set of good coilovers and lots of fancy purple ****. In the end, yeah maybe a few extra .0X g's, or a few .X seconds of a lap time but really good tires and suspension tuning will will bring the difference down to what's the real reason for wanting to do it.

WingsofWar

Wow i really like that statement.

I am going to have to disagree with Will also, I believe that R-Compounds are not band aids. They work in tandem with the suspension. Upgrading the tire grade does target those specific areas in which are weak. Such as upgrading bars and arms and bushing which target their respective areas which are weak. I believe band-aids are more related to helping areas which not weak, but pose a negative threat against a system.

ITSWILL

iTrader: (12)

I only included R-comp tires because so many people use them with out ever modifying their suspension.

With a proper suspension they are key.

MaczPayne

iTrader: (5)

R-comps are only a bandaid for poor driver skill. When talking about suspension, tires are a big big upgrade!

wrankin

I don't think that there is any debate here. For road racing applications, it is best to eliminate the DTSS, if for no other reason than to keep the back end "predictable" under heavy braking.

If you want to go and look at radical suspension design using stock FC components as a base, then head on over to the Locost forum and read up on what some of those guys are doing in terms of suspension design and construction from scratch.

http://www.locostusa.com/forums/

Right offhand, I think that the big challenge would be in fabricating and reinforcing the upper front pick-up points. I am not sure if you have enough chassis metal where you need it.

It would be an interesting project.

pfsantos

iTrader: (1)

One can justify re-designing the FC suspension many ways - knowledge gained, exclusivity, wanting to mess around, eating up free time to keep one's *** out of trouble, etc.

The way I see it is a lot of work for little gain. Time and money (time IS money) which could be spent somewhere else. Obviously, this has a lot to do with your situation in life and many other factors. I for one have two kids and I have enough distractions already. I may be going off topic, but everything one does and one's decisions are based on many, many factors.

Just to ramble on, I could see this making a good thesis for an engineering student, no?

WingsofWar

You are exactly right, i am hoping for all of us here to kinda discuss the implications and such just for future reference. So if someone who has that background or is a student, and wants to take on this massively complex task, this thread would be a good starting point. Although this thread should belong in the Suspension/Wheels/Tires/Brakes section of Tech and Performance because its direction is more closely related to dedicated racing applications. For street or semi-road racing its obvious that the OEM strut design works very effectively, but how efficient it works is up to the tuner.

I am also going to apologize to everyone if the topic i started seems vague, especially since it may sound like i am actually trying to do something that is "over the top" even for a professional. As if the FC3S is trying to compete in F1 or something lol (but if i saw that id eat my jock strap). I am gona say this now, i have no intention of building such a design and already knew of its complexity, I just thought i would share some ideas and have a discussion about it.

MaczPayne

iTrader: (5)

No worries. One thing is for sure though:

Whoever goes through hell and high water to give the FC a completely new suspension design must LOVE the FC. Hell, he could have gotten another car and be done with it!

NotTTT

Masturbation accomplishes 75% of those four objectives.

ITSWILL

iTrader: (12)

pfsantos

iTrader: (1)

Which ones? Wait - this isn't the lounge.