Seeking MK1 VW Rabbit Suspension Setup Advice

And as far as setting up the Ground Controls go I have a couple questions too since I’ve never put together a set of them myself.

I checked into a used set a while ago and I was told that one set of springs were 8” long and the other were 7”.

Are the 8” front?

Can I run 7” all around so I can swap springs back to front if needed?

Assuming I am shortening springs up front with 7” springs, would I have to move my collar seat up from the stock cup on the strut bodies 1”?

If I’m scavenging for used setups what kind of interchangeability would I have with other cars like a MK2 setup?

Is there a certain length and diameter sleeve I would be after if I have to get even more creative for finding a set?

FYI I won’t be skimping on the struts though. I do want to buy them new and have the warranty.

You can actually run longer springs in the rear then in the front. Seven inch is what I would and do run in the front. I would even do 6 inch if I found some cheap. I have run as tall as 10 inch in the rear as my Bilstein threaded body shocks allow that tall of a spring and still get the car to the preferred ride height.

If you want to ever discuss VW's just PM me. I live just over the IL/IN border in IL. I have made some custom parts for my race car such as camber plates, spherical bearing LCA's, and few other things.

jimbbski wrote: If you want to ever discuss VW's just PM me. I live just over the IL/IN border in IL. I have made some custom parts for my race car such as camber plates, spherical bearing LCA's, and few other things.

No kidding? Do you happen to know Chris Schafsma (sp?)? He races ITB in a MK2 and he's pretty involved in that. I knew him from back when I lived in Chicago from 2004-2007 and I used to race Autocross with the Chicago Volkswagen Organization Club.

Once I have the rabbit all back together again this summer I'll have to meet up with you sometime. I'm only about 2.5 hrs away from Chicago.

I appreciate your offer to PM you questions too Jim but I figure I might as well keep posting them here since people have been so helpful.

So based on an old thread I found on vwvortex and your last comments I have a whole bunch more questions.

Can you explain the effect of, and the theory behind longer spring length being beneficial?

By that logic, am I better off having a longer sleeve and a longer spring with a lower sleeve stop?

Someone on vwvortex pointed out the idea that instead of welding a stop I could simply run a 7” sleeve that sat on top of the flanges for the strut mounts. Is this a good direction to go in too vs. a shorter sleeve like a GC kit that rests upon the ground down spring perch or a welded in ring?

Multiple people have mentioned 7” springs being the ideal length, is there a reason for that?

Likewise, what can I get away with for a rear length? I’d like to buy the same length so that I can decide if I want to run a rear spring bias/no front bar or a front spring bias/larger rear bar. If I can do 7” or 8” springs at both ends and swap them at will that would be ideal to me.

Would 8” up front likely start to interfere with the tire?

This is another stupid question but I have to ask it. Technically the length of the spring and the sleeve length shouldn’t matter should it?

In other words, whatever both are the height of the car is the height of the car, and I should consider my adjustments to be against the stock height (which I can record because it IS all stock now) and whether or not the control arms are parallel?

Is there any good reason to cut down the length of the strut housings or am I good if I just cut the factory cups off and weld in a new stop?

I’m sorry that I’m asking a billion questions here but I REALLY appreciate all of the advice I can get and it sounds like some of you have some really strong, “been there done that” racing experience that would help me out.

If you consider a given ride height and a given spring rate, the length should be of no consequence whatsoever.

There is a wealth of knowledge about VW setup out there. There is also a wealth (poverty?) of superstition. Separating them is not always trivial.

I am not a VW expert, but I will make this observation: Whether or not having the control arms parallel to the ground is a good reference point (and it kills me that people just say "parallel" without giving a reference to what they're supposed to be parallel to), there is nothing magical about having control arms parallel to the ground. The result of doing that will be a specific instant center (the location where a line extending inward through the control arm intersects a line perpendicular to the line between the strut tower bearing and ball joint extending from the strut tower bearing inward) and a specific geometric roll center (the intersection of lines drawn from the left and right instant centers back to their respective contact patch centers).

The "horizontality" of the control arms is in and of itself meaningless because the forces from the wheel are not fed through the control arms alone, but the structure comprised of the lower control arms and the struts. Recipes can be very useful, but do not confuse "one cup flour and 1 tsp baking powder" with an explanation as to why the pastry is tasty.

I agree wholeheartedly Ransom. Especially in the VW enthusiast world, there's a strong division between "show" and motorsport" these days so I hear chatter from both sides. The 100% show guys that are toying with offset and stretched tire size until they have wheels that are perfectly nestled into the wheel well look great parked but beat the crap out of the car driving it and I can't see the justification in that.

The strictly motorsport guys will preach up and down that anything other then parallel control arms (which is really not easy to define as you pointed out) will vilify anything other then that and proclaim that you have "ruined the car" by going lower then that.

At this point everything I'm worried about has been entirely speculative until I get the suspension on the car and actually DRIVE it and see what effect the height adjustment has on how the car behaves. I'm leaning more and more towards saying "FK style points" and tayloring the car to how it drives not how it looks though. If I determine that an extra 1/2" or 1" of drop to eliminate the wheel gap makes it handle like crap then I'm just gonna raise it up again to a useful autocross height and call it done. I'm really leaning towards an old school period correct look with some 13" mesh wheels like Vials, Rikens, etc. and gumball tires anyway.

I bought this car because I wanted something that had proven racing capability, light weight, and great handling. I could be like any other jagoff at most VW shows these days and take a bone stock car and put airbags on it and the "flavor of the moment" wheels on it to be anointed "cool" if I wanted to but that's not my goal. I have friends who have their cars so low on coilovers that they get to the show and proclaim "Man I shouldn't have filled the gas tank up completely, I was rubbing the whole way!" That defeats the purpose of the car IMO.

Contradiction wrote: I appreciate your offer to PM you questions too Jim but I figure I might as well keep posting them here since people have been so helpful. So based on an old thread I found on vwvortex and your last comments I have a whole bunch more questions. Can you explain the effect of, and the theory behind longer spring length being beneficial? By that logic, am I better off having a longer sleeve and a longer spring with a lower sleeve stop? Someone on vwvortex pointed out the idea that instead of welding a stop I could simply run a 7” sleeve that sat on top of the flanges for the strut mounts. Is this a good direction to go in too vs. a shorter sleeve like a GC kit that rests upon the ground down spring perch or a welded in ring? Multiple people have mentioned 7” springs being the ideal length, is there a reason for that? Likewise, what can I get away with for a rear length? I’d like to buy the same length so that I can decide if I want to run a rear spring bias/no front bar or a front spring bias/larger rear bar. If I can do 7” or 8” springs at both ends and swap them at will that would be ideal to me. Would 8” up front likely start to interfere with the tire? This is another stupid question but I have to ask it. Technically the length of the spring and the sleeve length shouldn’t matter should it? In other words, whatever both are the height of the car is the height of the car, and I should consider my adjustments to be against the stock height (which I can record because it IS all stock now) and whether or not the control arms are parallel? Is there any good reason to cut down the length of the strut housings or am I good if I just cut the factory cups off and weld in a new stop? I’m sorry that I’m asking a billion questions here but I REALLY appreciate all of the advice I can get and it sounds like some of you have some really strong, “been there done that” racing experience that would help me out.

The 7"spring in the front is because it will fit and the tire will be below the lower part of the spring perch in most cases. This will allow you to run a wider tire and/or add neg. camber at the steering knuckle attachment bolts. I do both, I added wheel spacers (3/8 inch) to give me the extra clearance so I can add as much camber there. I fine tune the camber at the top strut mount. You can run a long sleeve that rests on the strut mount but it does add thickness to the strut housing that will reduce the amount a camber you can add at the knuckle mount. If you can get what you want/need at the top mount then the issue of clearance is moot.

I use longer springs in the rear because I can and they are easier to find used. The 6-7 inch CO springs in the right range don't come up for sale used on the net all that much and when they do they sell quickly and for a price sometimes higher then I want to pay. If you are not in a hurry and you visit enough sits where things like this are sold you will eventually score a set or two. Once you find the right set up you can always sell the extra spring sets, most likely for what you paid for them, if not a bit more.

The key is that the strut and spring should bottom out at the same time or the spring a bit later. This is what determines spring height & sleeve length. What I have done when using shorter sleeves is make some sleeve spacers out of some aluminum tubing with .090 thickness and the a slightly larger ID as the struts OD. The spacer can rest on the strut mount and the sleeve above that. Keeping the spacer tube thickness to .090 means little reduced tire clearance. Having a lathe does allow me to start with a thicker piece of tubing and turn it down or open the ID to any size I need.

Spring length does have an effect but really in our case it won't make a noticeable difference other then the size factor and fitting longer springs on a car vrs shorter ones.

Thanks Jim.

The 7" spring makes sense when you describe it that way.

To clarify a bit further do you think that 7" springs are long enough in the back as long as I set my circlips to locate the rear sleeve high enough?

I like the idea of ordering 350/450 springs so I can swap them front to back if I am not happy with the rear spring weight bias to start with. It looks as if I have found a 16v rear bar so I plan on doing 350 f/450 r with no front bar and a 16v rear bar to start with.

Are you running camber plates on your car then I'm guessing?

Since I'm curious too what wheel size and offset are you running?

A friend of mine has some lightweight 15" wheels that were on another 84 GTI autocross car and I'm going to look into buying those. I'm guessing they are 15" x 7". Not sure on the specs yet but he's going to look at them for me soon.

Contradiction wrote: Thanks Jim. The 7" spring makes sense when you describe it that way. To clarify a bit further do you think that 7" springs are long enough in the back as long as I set my circlips to locate the rear sleeve high enough? I like the idea of ordering 350/450 springs so I can swap them front to back if I am not happy with the rear spring weight bias to start with. It looks as if I have found a 16v rear bar so I plan on doing 350 f/450 r with no front bar and a 16v rear bar to start with. Are you running camber plates on your car then I'm guessing? Since I'm curious too what wheel size and offset are you running? A friend of mine has some lightweight 15" wheels that were on another 84 GTI autocross car and I'm going to look into buying those. I'm guessing they are 15" x 7". Not sure on the specs yet but he's going to look at them for me soon.

Seven inch springs may fit or they may actually be to short. The rear suspension has more travel then the front. The shortest spring I tried in the rear was 8 inch and I would not want to use anything shorter.

Yes I have camber adjustable top strut mount that I made myself. I am currently using a third design. The first set were designed to fit the stock hole in the fender but they didn't give me enough adjustment range. The second set required making the hole bigger and they were better. The third set required a bit bigger hole but offset to the center line of the car to increase neg. camber still further. I did this so I could reduce the camber dialed in at the strut-to-knuckle joint for extra tire clearance. I hope to run 225/45X15 tires at some point. I am currently using 205/50X15 on 15X7 inch Enkie RFP1 wheels.

Thanks Jim,

I'm finally getting close to ordering the suspension now. Waiting on the rumored Koni Sale that starts on March 1st.

So based on what you have said 8" rear springs it is. I was hoping to be able to swap them from front to back if I wanted to, but it just doesn't sound like a good idea if 8"s will interfere with the front tire and 7"s are too short in the back.

I have a couple other questions for you now.

Is it worth adding tender springs to the coilovers? Am I ever going to likely unseat the springs when I am getting lift on the rear wheel around a corner or when I have the car jacked up to remove a wheel, etc?

Do you run any kind of bumpstops on your car? If so what length?

Any particular company that sells them that I should look into?

I don't use tender springs. I don't see the need of them on a road race car. You can use then if you want to spend the money and/or think you need them but that's up to you. A pure street car may need them but then on a street car the spring rates are softer and I would use taller springs so that may negate the need for tender springs there.

Do use bump stops. Bilstien struts as opposed to all other common struts for the A1 don't use bump stops so depending on what brand of strut/shock you have use them if there is room. Also just because something is sold for use on the front doesn't mean you can't use it in the rear.

Here's a place that sells a selection of them. http://www.germanautoparts.com/Volkswagen/Rabbit/Suspension/27 Some other parts sources.

http://www.autohausaz.com/ http://www.parts4vws.com/

Back from the dead on this one. I spent all of last summer and fall wistfully staring at my poor neglected dusty car in the garage when I dragged the lawn mower out because I kept saying "well the next show is in 4 weeks and there's no way I'll get it done by then."

Now I'm going to get serious on it.

About the last thing I need to decide on here is brake pads.

I'm hoping some of you guys that replied before might have some advice on that.

The obvious choice to me is some Hawk HP pads, but I'm torn between the HPS and HP+

I had HP+ on my 98 Jetta GLX that I autocrossed with and while they stopped great, they were HORRIBLE for noise and brake dust. Like bad enough for people walking on the sidewalk to look because they heard me braking and were probably thinking to themselves "Oh s**t is that fool gonna be able to stop?" loud. I don't necessarily want to go through that again.

For what I'm using the car for are the HPS enough, or would the HP+ really pay off?

jimbbski wrote: The 16V Scirocco front brakes require Scirocco front bearing carriers. The mounting lugs for the calipers are in a different position then other MK 1 carriers.

Not true. You can put the 10.1" brakes on any MKI knuckle. In fact they don't even have to come from a 16v Scirocco. You can use any 10.1" VW rotor, and the Scirocco calipers and carriers are the same as the Audi 4000. The only difference between the Scirocco 16v knuckles and the rest of the MKI knuckles is the drive axle clearance. You can't run the 100mm CV joints on anything but the Scirocco knuckles.

I lucked into a great autocross set up on my 16v Rabbit. I put it together as cheaply as possible because it was a challenge car build, and it turned out to be one of the best handling MK1's I've ever driven.

It's a gutted '77 Rabbit with 16v Scirocco brakes all the way around it, 16v Scirocco front and rear sway bars, 16v Scirocco lower brace, Neuspeed race springs with I think one coil cut off of them (ebay specials), and whatever crappy struts were on the car when I got it. I'm sure the struts could stand to be upgraded.

It's seriously one of the most neutral cars I've ever driven. It will oversteer before it will understeer (but can do either if you make a mistake!), but it's kind of hard to make it do either. It has placed in the top 10 in the Challenge autocross a few times.

One piece of advise I would give is to NOT upgrade the rear axle bushings. If yours aren't shot, leave them be. They're designed to pivot a little bit, so when you lift the inside rear wheel, the outside rear wheel actually shifts back and tows out to give you passive rear steering. If you put poly bushings in the rear beam it pretty much kills the passive rear steering.

I didn't read the whole thread, so sorry if any of my info was a repeat or unneeded.

16vCorey wrote: One piece of advise I would give is to NOT upgrade the rear axle bushings. If yours aren't shot, leave them be. They're designed to pivot a little bit, so when you lift the inside rear wheel, the outside rear wheel actually shifts back and tows out to give you passive rear steering. If you put poly bushings in the rear beam it pretty much kills the passive rear steering.

This does work remarkably well.

16V Corey; I hear you on the rear axle bushing but some poly bushing are not that hard and do give a bit under load. My set up on my '88 16V Scriocco is #450 front & #500 rear with stock rear sway bar, modified stock "K" brace and custom home made camber plates and the "mini slip" differential mod. The car is near netural, it will understeer on slow turns, then as the speed goes up can be made to oversteer just a bit with a slight lift on the faster ones. The car always will settle down "right now" if I give it more throttle in the middle of a turn. Sometimes on long turns, just for fun I make the back end dance. I.E. change the cars attitude from a bit of oversteer to a bit of understeer by adjusting the level of throttle I apply.

I can't wait but I have 3 more months before I can get the car on track.

16vCorey wrote:

jimbbski wrote: The 16V Scirocco front brakes require Scirocco front bearing carriers. The mounting lugs for the calipers are in a different position then other MK 1 carriers.

Not true. You can put the 10.1" brakes on any MKI knuckle. In fact they don't even have to come from a 16v Scirocco. You can use any 10.1" VW rotor, and the Scirocco calipers and carriers are the same as the Audi 4000. The only difference between the Scirocco 16v knuckles and the rest of the MKI knuckles is the drive axle clearance. You can't run the 100mm CV joints on anything but the Scirocco knuckles. I lucked into a great autocross set up on my 16v Rabbit. I put it together as cheaply as possible because it was a challenge car build, and it turned out to be one of the best handling MK1's I've ever driven. It's a gutted '77 Rabbit with 16v Scirocco brakes all the way around it, 16v Scirocco front and rear sway bars, 16v Scirocco lower brace, Neuspeed race springs with I think one coil cut off of them (ebay specials), and whatever crappy struts were on the car when I got it. I'm sure the struts could stand to be upgraded. It's seriously one of the most neutral cars I've ever driven. It will oversteer before it will understeer (but can do either if you make a mistake!), but it's kind of hard to make it do either. It has placed in the top 10 in the Challenge autocross a few times. One piece of advise I would give is to NOT upgrade the rear axle bushings. If yours aren't shot, leave them be. They're designed to pivot a little bit, so when you lift the inside rear wheel, the outside rear wheel actually shifts back and tows out to give you passive rear steering. If you put poly bushings in the rear beam it pretty much kills the passive rear steering. I didn't read the whole thread, so sorry if any of my info was a repeat or unneeded.

Thanks for the reply Corey.

I did get a chance to verify the 10.1" brake setup a bit more and I opted to stick with the stock GTI knuckles to keep 90mm axles.

You have a great point on the rear beam bushings too. I bought a spare beam for parts so I could refinish it so I think I still have my original stock ones that came with the car.

What do you think of the Autotech ones in this link though?

http://www.autotech.com/product/suspension-bushings/10-540-001K.html?fromcat=mk1-rabbit

These are what I reluctantly ordered because new factory bushings are NLA from VW. It sounds like they are on the softer side. Worst case scenario I can always swap back to the orginals I suppose.

Back to my last question, what are you guys running for brake pads?

If you have ran Hawks before are the HP+ enough of a performance gain over the HPS to live with the extra noise and dust?

If you're just doing street driving and autocross, HPS is enough. You might even be able to get away with stock pads, you need very little brake heat capacity for autocross (that's why you see Emod cars running puny brakes to save unsprung weight), it's more a matter of brake feel. Street driving will get your brakes a lot hotter than autocross.

Anybody have any opinions on Porterfield R4-S pads? I actually found out that they make 200mm rear drum shoes with R4-S compound! If I decide the shoes are worth it it would make sense to do the pads in the same material.

I've heard good things about them, they're one of the pads I looked at myself, along with the R4. They'll do fine for street and autocross.

I never felt the need for anything other than stock brakes on my autox-only MK2 Golf.