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Project Black Dog Part 1b: H&R Cup Kit suspension installationFrom the April, 2009 issue of European Car By Dan Barnes Photography by Dan Barnes
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Kosei K1 Racing wheels, 7x16-in.,... Kosei K1 Racing wheels, 7x16-in., were supplied by The Tire Rack. These are high-quality, lightweight, cast alloy wheels. They aren't as light as the best forged wheels, but they are highly affordable and fall comfortably under the 1lb-per-inch rule we like to follow on wheel weights. Plus, we think they look great. Sister magazine Sport Compact Car used them on its MR2 Spyder project, and they survived near-rally abuse. We had them shipped with 205/45-16 Kumho Ecsta Supra 712 tires mounted and balanced, another budget-conscious choice. We may eventually replace these tires with more-serious rubber in an attempt to get some handling numbers, but for now they provide a comfortable, quiet ride. They are lasting well, and supply considerably more grip than the worn stock tires. When we tested this Jetta initially, it took 167 ft to stop from 60 mph and cruised through the slalom at 60.5 mph. The slalom driver had no kind words for its handling, and the skidpad revealed only 0.77g of cornering power. Clearly, the suspension, wheels and tires were the first and most important place to start making improvements. H&R has touted the benefits of its Cup Kit suspension systems for several years. european car had yet to evaluate one on any car, so we took this opportunity to do so. H&R's Cup Kit is a combination of shortened struts and shocks with stiffer springs. Most aftermarket performance dampers are stock length so they can also serve as replacements with stock springs, but that limits suspension travel when the car is lowered. H&R's Cup Kits, because they are designed to achieve significant lowering from the start, maintain as much travel as possible with their low ride height. The spring rates and damping are engineered by H&R to work perfectly together in a street application. Some Cup Kit applications are infinitely adjustable in rebound damping, but this one is not. Because this was european car's first experience with a Cup Kit system, I chose to install it myself in the Primedia tech center, which has an Autolifters two-post lift and a large selection of Craftsman tools. I brought my own Sir Tools spring compressor, which worked perfectly. (For more information, see Tool of the Month, December 2000.) I have changed struts on many cars. This Mk3 had the fewest attachment points of any, and was somehow still the most-involved procedure. In addition to the notes here, we strongly recommend following the instructions in the Robert Bentley manual, p/n VG99, or Volkswagen p/n LPV 800 116 at your dealer. It has the correct torque specifications for all fasteners, and exploded parts diagrams that make the process clear. The H&R Cup Kit turned out to be an excellent choice for a budget-priced, matched suspension set. The author hasn't stormed up any mountain roads with it yet, but the ride and handling on everyday roads is excellent. The vehicle is lowered considerably, with no rubbing, and suspension travel doesn't appear to have been adversely compromised. The "next first step" is a 280mm front brake upgrade from Autotech. That installation will be here next month. After we get the chassis dialed to our satisfaction, we'll go to the test track and measure the improvements. Hopefully, this black dog will begin to be capable, faithful companion.  H&R's Cup Kit is not a full-on...  H&R's Cup Kit is not a full-on coil-over system, as ride height is not adjustable and the springs are full-bodied. Volkswagen factory upper seats are used, and the lower seats look similar to the originals. In fact, we were very impressed with the overall presentation: with few exceptions, these parts resembled the factory parts and installed just like them.H&R includes spacer rings that can be installed below the lower spring seat on the shock shaft to increase rear ride height about a centimeter. They were packaged separately, so I figured they were optional (such as when heavy passenger or cargo loads are expected) and didn't install them. Having seen the car on the ground, I'd use them if I were to do it over again. Installing them after the fact requires going one step further than when leaving them out.  As with any car, start by...  As with any car, start by removing the anti-roll bar end links. They will limit suspension movement and make problems later if you don't do it now. This is easy to do on the ground, but be sure you look where you're putting the wrench and don't go by feel--the bolts holding the ball joint to the control arm are about an inch away and fit the same size socket. Of course, I merely observed this with my eagle eye. I would never make that mistake. But if you do, relax, because there are two more bolts holding the ball joint in position. Just put it back, torque it to spec and don't tell anyone.  The brake line slides out...  The brake line slides out of the bracket holding it to the strut body, and the tiny stock front brake discs make access to the strut-to-steering knuckle clamp bolts a cinch. The brake line bracket must eventually be transferred to the new strut, a task most easily done off the car.Camber adjustment is achieved by slotting the holes in the strut that the steering knuckle clamp bolts pass through. This gives a wide range of movement, but means any time these bolts are loosened, a professional alignment is an absolute necessity. That's a good idea on any car, but you can let it slide on many older Japanese cars, which used an eccentric cam to set the camber with some repeatability.  The strut top nut is accessed...  The strut top nut is accessed from inside the engine compartment. Hurried mechanics often use an air-powered impact wrench, but it is better to use a deep-offset box-end wrench with a long hex key holding the strut shaft to remove the nut. I couldn't find a 22mm deep-offset box-end wrench in the Craftsman catalog, so I went to Harbor Freight and bought a whole made-in-India set for $9.99. On the Jetta, the wrench didn't fit inside the strut top mount at first, so I took the 22mm wrench over to the big, bad, belt sander and made it fit. I was amazed when the wrench didn't break. I began to feel a little cocky.  My cockiness soon dissipated....  My cockiness soon dissipated. I remembered an installation article I did a few years back (February, 1997, p. 64) where a Mk2's upper strut bearings were upgraded to Mk3 VR6 parts. On many Volkswagens, the upper spring seat is held to the strut shaft with a slotted round nut that requires a special tool. After two strikes at the closest auto parts stores, I borrowed one from Eurosport Accessories, which is fortunately just a couple miles from our offices. (Koni struts intended for a Corrado that I installed in another car came with this tool.)  With the Sir Tools spring...  With the Sir Tools spring compressor, the strut came apart easily, and the bump stop and upper spring seat and body mount were transferred to the Cup Kit strut. The instructions are very explicit that air or power tools should never be used with the compressor. As well, I find a little grease on the threaded shaft is a big help. Just be sure to store it where the grease won't attract dust and grit. I like wearing Mechanix Wear gloves when doing work like this to protect against skinned knuckles and keep the dirt out from under my fingernails.After reassembling the strut and tightening the nut, I found the upper body mount had play in it, just enough to make an irritating clunk. With the Volkswagen's generous rubber, it may not have been a problem, but I wasn't about to find out the hard way. The bearings in this car's body mounts were worn, and there was only one thing to do. Eurosport Accessories had Mk3 VR6 mounts in stock, so I upgraded. Besides being new and unworn, they use a stiffer rubber that will slightly sharpen the steering and improve the dampers' control of suspension movements. The mounts are packaged with a zip-tie holding all the separate pieces in the correct sequence and orientation. It's not obvious what that is once you've separated them; leave the second mount as it comes so you can refer to it. Conveniently for the future, the VR6 mounts use a conventional hex nut instead of the slotted round one.Reinstalling, I discovered that my Harbor Freight wrench set didn't include a 21mm, which was required by the new VR6 nut, as well as the new self-locking nut supplied by H&R for the upper mount. I was forced to use the time-honored but non-ideal method: an impact wrench. The camber-adjustment slots in the H&R Cup Kit struts exactly matched those in the stock struts. I put the knuckle somewhere in the middle of the slop, installed the stock wheels on the front and instructed the owner to get an alignment ASAP, warning him that his steering would probably feel funky until he did.When both sides are done, don't forget to reconnect the anti-roll bar end links. We'll be upgrading the front bar and adding a rear one later, so we left these stock for now, but replacing the rubber cushions with polyurethane should make the bar more effective.  The rear dampers should have...  The rear dampers should have been easier to change, as they have only two sets of threads: one at the top and one at the bottom. The lower bolt comes out as easily as it looks like it should, though one side of our car still had a protective plastic cover to prevent accessing the head of the bolt with a socket. It pried off easily with a screwdriver. Since there was only one, and its primary function seemed to be charity to spiders, we didn't put it back on. I found that removing the lower shock bolt from both sides allowed the beam to droop just far enough to be out of the way, and that the floor jack I had in position to support the beam was not necessary.  To remove the upper mount,...  To remove the upper mount, fold the rear seat forward and fold up the carpeting at the leading edge of the rear deck. Remove the rubber dust cover to reveal a cad-plated nut. It can be removed with an open-end wrench. I didn't find it necessary to hold the flats of the shock shaft with a Crescent(R)-style wrench, but you may. Keep parts in the sequence and orientation in which they are removed. The nut is followed by a large dished washer, then another nut, which required another offset-box wrench, 17mm. And lots of patience. Clearly, these are installed at the factory before the rear deck, which is installed before the inner upholstery on the C-pillars. I thought about removing some trim to make access easier, but decided it wouldn't save a bit of effort.  When the second nut is removed,...  When the second nut is removed, the shock and spring can be lowered from the car. This is what you will see. Be careful: in addition to the rubber mount and steel cup still above the body, there is a larger rubber mount and identical steel cup that will stick to the underside of the body, but only long enough for you to turn your back and miss seeing what it is and where it goes when it falls. This is where I was really, really glad to have the Bentley manual. In addition to torque specs for everything, it had an exploded diagram of the rear shock assembly. Without it, I might still be scratching my head. There is a large number of parts involved in such a seemingly simple mount, and it's not obvious how they fit until after you figure it out. Transferring the bump stop, upper spring seat, and everything else required from the stock shock to the Cup Kit unit is easy, but it takes some attention. Use the diagram in the Bentley manual to make sure you have all the parts, and in the correct order. The thin metal sleeve that goes between the spring and the lower seat is easy to miss when it's dirty. (Despite having done this before, I made mistakes the first time and the second, but perhaps that was because I should have taken more breaks and not been in a hurry to get the job done so the car's owner could get to a Dodgers game. Thinking about it, there could be a lesson in that.) Assembly is the reverse of disassembly. That line is infamous, but it actually applies here. Putting the shock back in the car is a pain, but no worse than taking it out. Just be sure that everything is making sense, and don't tighten anything until it does. This would be a good time to survey what parts are left over. Not many are supposed to be on the ground at this point. H&R supplies a new self-locking nut that only makes sense to be used as the very final nut, but the factory nuts are jam nuts, not self-locking, so I retained the factory arrangement. I thought perhaps the H&R nuts were actually for the lower bolt, but it has a different thread pitch than the shock shaft. I found it easier to do both sides before reinstalling either lower shock bolt to the beam. Once that is done, the job is complete. Put the wheels back on, torque the lug nuts, and put the car on the ground. Go for a test drive. Listen for clunks, rattles, any indication that something is loose. Check for rubbing. Go over some bumps. If you're pretty happy with it on surface streets, take an on-ramp and see if anything rubs. While doing this, remember that your alignment is all messed up, so steering and general handling will probably not meet spec until that is done. Be careful, and be safe! Sources
Bentley Publishers
(800) 423-4595
www.bentleypublishers.com
Eurosport Accessories
(800) 783-3876
www.eurosportacc.com
Harbor Freight Tools
(800) 423-2567
www.harborfreight.com
H&R Special Springs
(888) 827-8881
www.hrsprings.com
Mechanix Wear
(800) 222-4296
www.mechanixwear.com
Sir Tools
(800) 845-4542
www.sirtools.com
The Tire Rack
(888) 541-1777
www.tirerack.com
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