Saturday, August 6, 2011

Project Sipster - Part 5 - Safer Sipster


Project Sipster safer sipster making it handle
Project Sipster Part 5 - Safer Sipster 
By Dave Coleman
Photography by Jared Holstein and Christopher Gifford

Safer. Yeah, that's why we put coil-overs on it! If it sounds like we're trying desperately to justify cool racey bits on our fuel sipper it's because we are. The plan was for the Sipster to survive past this series, and we wanted it to be a real, decent, driveable car. We had dreams of hitting our 7s, and then taking it to track days and beating up on Porsches. Imagine, as we did, driving 3 hours to the track, spending a day passing Euro-snobs, and then driving home on the same tank of gas. Uh... diesel. That's the real reason we were suddenly so safety conscious.
Speaking of safety, a few commenters chided us for lane-crossing in the lead shot of our "safety" story. Fear not. Here's the raw version of that lead shot: 
sipster can turn

The story:
Have you ever noticed how project Sipster looks at you like a puppy? Look at any picture of the front of our little Rabbit and you'll notice it always has its head cocked to the left a little bit, it's square little eyes just off from horizontal. It looks either a little sad or a lot stupid depending on your mood.

At first we wrote it off as an optical illusion. Then, perhaps the result of a suspension sagging with age. Now, as we pour over the car with Raffi Kazalkasjdfhan at Eurosport Accessories in Anaheim, California, it's becoming apparent the crooked stare is something more serious. This car has been crashed before. Every 28-year old car has been crashed before, but this one, apparently, was repaired by a buzzed chimpanzee. The front suspension mounts on the driver's side are a full inch lower than the ones on the right.

That seems like a reasonable enough excuse for going overboard and using what is essentially a race suspension on a car that we're supposed to be hypermiling.  The H&R coil-overs we're installing have adjustable spring perches, letting us adjust each corner individually to make up for the wonky body. Our bent Rabbit is that annoying wobbly restaurant table, and the H&R suspension is the packet of sugar we're jamming under the table leg.

sipster can turn

sipster can turn

Truthfully, we ordered the suspension bits before we noticed the crooked stare. Our original motivation was simple self preservation. We are not the manly men that inhabited the earth back in 1981, fearlessly cruising the streets without airbags, side impact beams or any hint of structural integrity; in all honesty, driving around in this little box kinda scares us. Since making an old car actually crashworthy is beyond even our powers of exaggeration, we're avoiding the whole crashworthiness issue by making the car easier not to crash. Handling and good brakes are our airbags.

The coil-overs are a start. We're also adding H&R anti-roll bars at both ends. On a GTI, a Scirocco, or a Cabriolet, the H&R anti-roll bars are upgrades, just like the stock bars but stiffer. On a Diesel they're a whole new concept. Our car never had any, which goes a long way toward explaining the terror with which we dropped into the corkscrew at Mazda Raceway Laguna Seca last week.

Not having stock bars means we also don't have any of the factory mounting brackets the H&R bars are supposed to mount to. This is one of the many times we'll be lucky we know Raffi. Half clean race shop, half clean parts warehouse, Eurosport thankfully still has one messy corner. It's into that messy corner that Raffi disappears, returning a few minutes later with a fist full of greasy little metal scraps that make it possible to bolt the sway bars to our little barless wonder. Plan to spend some quality junkyard time if you don't know Raffi. Eurosport also replaced the original rubber control arm bushings, which were on the rancid side of fresh, with shiny new red polyurethane units. 

sipster can turn
Our Rabbit came with no sway bars whatsoever. It was so unready for bars, we even had to drill end link mounting holes in the control arms. At the rear, we had to hit the junkyard to get some sway bar mounting hardware from a Rabbit Cabriolet. It's a shame I can't find pictures of that hardware, since Volkswagen did some seriously clever/goofy engineering back there. The rear bar is held to the rear twist beam with a crazy clamp that took us an hour of hammering and swearing to figure out.

sipster can turn
Even 28 years ago, our Rabbit's body wasn't strong enough to deal with race-stiff suspension and sway bars. Three decades of fatigue, crashes and primate repair jobs haven't helped. To make up for the fatigue, we're adding Eurosport braces all over the place. The lower arm brace that hangs under the engine is normally hard to install; strangely, it bolts straight to our car without complaint. The strut tower bar, which connects the front strut towers above the engine requires extensive modifications to deal with the chimp's handiwork. A third brace, connecting the rear suspension towers across the rear cargo area, drastically cuts into the amount of crap Jared will be able to carry around the country. The rest of us, though, think the handling gains will be worth the sacrifice.



sipster can turn
Getting under a Rabbit was a lesson in old-school minimalist engineering. I cut my wrenching teeth on Datsun 510s, which used beefy subframes for all the suspension mounting points. Rabbits, which are theoretically 6 years more modern, not so much. Not only do the front lower control arms bolt straight to the flimsy unibody, the part they bolt to is cantilivered out in space with very little support. These flimsy mounts are a great opportunity for guys like Raffi, who can look like a hero when his lower control arm brace makes a night-and-day difference in steering response. Rabbit control arm mounts are so flimsy they normally deform so far in normal usage that the brace doesn't even fit without some serious prybarage. How a car this bent could have control arm mounts still straight enough for the bar to just slide on is beyond me, but this car is chock full of the strange.


The scariest part of the corkscrew, truthfully, wasn't the steering delay, the body roll, or the relentless understeer, it was hitting the brakes at the entrance to the steep, downhill Rainey curve that comes next. Mashing the Sipster's middle pedal was like popping a parachute--a little, 6-inch G.I. Joe parachute--and then patiently waiting for it to slow the car down.

We had originally planned to install bigger front brakes from a Passat, but as Raffi correctly points out, the bigger calipers will only make the brake pedal squishy if we don't also swap in the master cylinder and brake booster from a Scirocco 16V, which we don't have. Putting stronger front brakes on without upgrading the rears would also make the brakes too front-biased, making the front brakes lock up well before the rears have done their best work.

Instead, Raffi suggests simply using the setup that has served his 178-hp Rabbit racecar for over a decade, slightly thicker GTI rotors, more aggressive brake pads, and maybe some rear wheel cylinders that aren't leaking, along with new shoes and drums. By now we've learned to do what Raffi says, and the improvement is dramatic.

sipster can turn

In all, we've added almost 40 pounds with these upgrades (24 pounds of sway bars, 13 pounds of braces; the coil-overs and brakes are basically a wash), which isn't ideal for either our acceleration or mileage goals, but those pounds may just help us live long enough to see those goals realized. A fair trade.

With the car now safe to drive 60 mph, we're getting serious about that 0-60 goal. So serious, we'll have results up next installment, along with a description of our visit from the torque fairy. See you then.

UPDATE:
Jared just helped me find the videos that went with this series. Amazingly, they're still up somewhere in the TopGear internet universe. Here's our handling video. 

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