Suspension set up [Archive]

05GLI

08-29-2006, 09:27 AM

How do you read the spring and shock rates? I am looking into changing my suspension but don't know how to read what I am buying? I don't want a random set up. I want a matched set. Due to engine up front I would need a heavier springs on the front right?

Note: I don't race but I drive in the canyons at least once a month.

Damon

08-29-2006, 10:07 AM

Spring rates are how "stiff" the spring feels. It's how much force needs to be applied to compress it. The stock GTI springs are something like 150 lb/in. Compare that to what competition folks may be using, which is in the neighborhood of 400 lb/in. I haven't seen a solid measuring stick for shocks.

Springs can also be progressive (rate increases exponetially as it becomes more compressed) or linear (constant rate of increase through compression). Most street springs are progressive (H&R, Neuspeed, Vogtland, etc etc).

If you want a nice, fully adjustable suspension where you know all of the factors - I say get Ground Control with Koni Yellers.

Go ahead and "lol @ GC - get real coils!"

Ground Control makes a solid product, and they will give you custom linear springs rates in adjustable perches, and the Koni's will give you the full range of adjustability for rebound. If you decide to play with your spring rates, they also sell new spring pairs.

(How did I become a little suspension nerd?)

05GLI

08-29-2006, 04:20 PM

Thanks for the info it honestly helps but....... How do I find out if a certain shock can handle we'll say a 500 lb/in spring? You can find most spring rates but Shocks seem to be a different story.

Skwurlz

08-29-2006, 04:38 PM

Schneller

08-29-2006, 04:47 PM

I would avoid Ground Control's if you want to go really low and maintain a decent ride. That, and they are prone to shift.

Cheers, Travis

If you want to go low, and handle, the limiting factor is your spindles; MkIV's arent meant to be lowered more than OEM sport height. Once you drop it, the geometry will be all out of whack, and the front end will roll like a torpedoed frigate in high seas. Trust me, I've done it.

You can find a shit ton of information on this subject on the 'tex's suspension forum...all the science you ever did and didn't want to know concerning the MkIV chassis.

Get the spindles, however, and she handles like a go kart.

Damon

08-29-2006, 05:53 PM

Thanks for the info it honestly helps but....... How do I find out if a certain shock can handle we'll say a 500 lb/in spring? You can find most spring rates but Shocks seem to be a different story.
Other than contacting the manufacturer, I'm not sure.

Lowering anything over 1" + MKIV = bad. The control arms go past parallel to the ground and your camber curve goes to poo. But!, a lowered euro looks soooo clean, oh the drama....

I've been trying to nail this jello to a tree for a while:
http://www.socaleuro.com/forum/showthread.php?t=12020

The VWVortex "Lowering vs. Handling Thread" (WARNING! It will make you cry..):
http://forums.vwvortex.com/zerothread?id=621342

I believe there is a 337 that goes to Fusion that is on KW V3 coilovers with H2 sport spindles that fixes the camber curve issue. I've been dying for a ride but haven't made it out in a month or so. I heard it handles like sex.

...and 500 lb springs are going to be brutal! :)

BLACK 1.8T

08-29-2006, 06:01 PM

I believe there is a 337 that goes to Fusion that is on KW V3 coilovers with H2 sport spindles that fixes the camber curve issue. I've been dying for a ride but haven't made it out in a month or so. I heard it handles like sex.

...and 500 lb springs are going to be brutal! :)

Yeah. That's Yoshi (Schneller here on SCE).

MikekiM

08-29-2006, 06:08 PM

If you're just looking for a daily driver kit there's a lot of choices out there. Most will improve the handling, look, and make canyon drives a lot more fun.

What's your budget?

bugzy

08-29-2006, 06:17 PM

Budget is the key.

Stiffer spring rates usually means stiff ride. Most street coilovers have spring rates from 300-450lb

Track/street end up being 400-600lb
Track end up being 600-1200lb

but then shocks that are tuned to those spring rates become really important for the proper performance. Stiff spring without the proper shocks, is just as bad

which is way going with a tried and true setup like the H&R, Vogtland, Eibach, KW's are usually the best bet for street use

Talk to some of the local forum supporters like Troy@group5 or MikeKim@purems ... they can be a great resource

Damon

08-29-2006, 06:22 PM

Spring rates shouldn't really affect the damper or strut, but travel will. You need to match the drop rates with the shock travel. You don't want to be bottoming out the shock. I run a Weitec TX coilover setup with custom rate KW springs, but they are measured in N/M.
If you have stiff springs and soft shocks (underdampened), the life of the damper will be shortened because the system goes through more "up-down" cycles before coming to rest. All dampers are designed to go through a certain amount of these. So, everytime you hit a bump, the shock travels 3 times instead of 2.5 (for example), and the lifespan is reduced.

Dampers are meant to control the number of cycles the suspension goes through before coming to rest. You hit a bump, how many up-downs does it go through to stablize? 1, .5, 4? This is rebound.
They also have some doing in resisting compression.

If the springs are too soft, the dampers bottom out internally and "kablooey". The internal bits in the damper get squeezed too tight and it's effective dampening force is reduced to 0. In other words, your car feels like a water bed. Lowering the car compounds this problem since the shock is already partially compressed. If you go balls out low, the shock is nearly fully compressed.

Ways of combating this include:
Don't lower the car (duh!).
Get stiff springs (your back hurts).
Get stiffer dampers (back hurts still, wife hates you, dog throws up, etc).
Get "sport" dampers. Koni and Bilstein have shortened internal shafts for lowered cars so they do not bottom out so easily. This is why I don't recommend the KYB or Bilstein Touring shocks-they have long shafts. (Insert penis joke.)

The problem with most coilovers is that they do not want to make the ride uncomfortable for the customer. So, they give you softer springs with a 3" drop, and the first big hole you hit....

If I am wrong about anything, please learn me up! :)

Damon

08-29-2006, 06:23 PM

Yeah. That's Yoshi (Schneller here on SCE).
Ah! I still say we need a "FACES OF SCE" thread.

g60racer

08-29-2006, 09:10 PM

500 lbs is really not that stiff, especially on a car that weighs 2700 lbs+.

I have 800 lb H+R race springs (rear ones) on my Corrado, which weighs 2600 even. Matched with Koni adjustables, it's definitely stiff but still streetable. It's a track dedicated suspension, set up specifically for Buttonwillow and Willow Springs (a few adjustments made depending on track configuration).

I do know a couple guys running 800lb springs on their H+R coilovers here in SoCal on their R32s, and they're happy but the cars are definitely *stiff*. Write it off to that Mk4 chassis being ridiculously firmer structurally than the A2 frame, but it's a totally different ballgame than my Corrado, which feels it's doing the twist when transitioning hard.

For street use I would stick with something in the 300-400 range. H+R sports for Mk4 are right in that range, so are Eibach sports.

Slapshotnerd

08-29-2006, 10:33 PM

budget is going to be your biggest limiting factor. Give us your budget, and we'll give you some suggestions.

ps - i'm a huge fan of the cup kit for most first time "lowering" customers. Great drop, no worries about adjustability or tuning or anything like that (coilovers should REALLY be aligned and counterbalanced every single time you make an adjustment. Most people never get them counterbalanced, and only aligned after the initial drop, which can affect your driveability dramatically

Schneller

08-29-2006, 11:04 PM

Dampers are meant to control the number of cycles the suspension goes through before coming to rest. You hit a bump, how many up-downs does it go through to stablize? 1, .5, 4? This is rebound.
They also have some doing in resisting compression.

If I am wrong about anything, please learn me up! :)

Just a clarification: compression is when the shock, duh, compresses. Rebound is when the shock uncompresses. My point being: up's and down's include both compression and rebound damping.

:tup:

Schneller

08-29-2006, 11:05 PM

Yeah. That's Yoshi (Schneller here on SCE).

Shhhhhhhh! You're giving away all my secrets!!!

:smokem:

Remus6

08-29-2006, 11:33 PM

Any suggestions on a good place to take my car to for an allignment? I got the Koni cup kit for my car, went to 2 places in Chula and they did not have the software for my car. I have an 06 Rabbit btw.

Damon

08-30-2006, 07:21 AM

05GLI

08-30-2006, 08:53 AM

I am trying to keep my budget below a grand. I getting new rubber this weekend so that puts me away from the coils. I currently have a set up that gives me a 1.5" drop and I don't want to go any lower. The problem is on certain corners the front seems to bounce a little while in the turn. It isn't bad but it is a little noticeable. I am doing my research this time to fix the problem. At a 1.5" drop should I get drop spindles? Or better yet, do I need them?

05GLI

08-30-2006, 09:35 AM

Also What will drop spindles actually do? I kind of understand what they are for but what do they do? Do they actually adjust in degrees or do they just drop a little in inches to keep a safe geometry for the suspension?

MikekiM

08-30-2006, 10:04 AM

At around a grand, your choices will be limited to mostly spring/shock kits, if you're including installation and an alignment in that budget.

It sounds like you've already got some lowering springs, but probably not good shocks to dampen the higher spring rate.

Now whether you "need" drop spindles or not is up for arguement, and depends mostly on your particular use of the car.

They help maintain proper geometry so the suspension has the best chances of operating correctly and most efficiently. The spindles on the market don't change the ride height much at all. They aren't lowering spindles in the sense that they lower the car. They simply allow for you to lower the car and maintain proper geometry.

They're an expensive option to consider since you need bearings and hubs, and some cases new ball joints. There's considerabl labor involved as well in assembly and an alignment. These don't have any bearing on ride comfort, only transitional handling.

Hope that helps!

bugzy

08-30-2006, 10:06 AM

Skwurlz

08-30-2006, 12:43 PM

Ok, lot of info in here, and most of it is correct.

I run Weitec TX's like I said before, which has adjustable dampning. I have it set two turns from full stiff with custom KW springs. The car is stiff, the way I like it. I can sit on the fender and it doesn't sag. I also run Ingalls engineering adjustable ball joints. My camber is at -2 degree's up front. My rear camber is around -3.5 degree's.

I looked into doing the drop spindles to correct the geometry, but it's just too damn expensive, and absolutely pointless unless your racing. Street driving with those spindles increases the risk of bottoming out your oilpan. Since my car is also my daily driver, it's a no-go.

I just ran Mullholland last Sunday and the bikes couldn't pass me. They had a hrd time keeping up in the twisties.

I can get ya Weitec's for $749 for GT and $899 for TX. You won't be disappointed.

Cheers, Travis