Jan 292013
 

If there is one thing that the CRX project taught me, it would be: when dealing with an older car, expect the unexpected. The 850, though mostly reliable, has proven to be no different.

The Brakes

Even though it passed its first road test, I still had some concerns. Most notable was the annoying shrieking sound the brakes made for the first ten minutes of every drive. Although both the front and rear pads still had plenty of meat, all four rotors were gouged and the pedal vibrated whenever I pressed it. Any of them could easily have been the cause of the noise, but I my discerning ear said the fronts were the primary culprit. I decided to go with the best inexpensive pads and rotors I could find. With those procured, I pulled the car in to my service bay and, almost immediately, things started to go badly. When compressing the driver’s side caliper, I noticed fluid coming from the piston seal.

I should note here that I have done dozens of brake jobs over the last couple of years and never had a single problem with a piston seal. When my personal car is in my bay, though? Naturally, that would be the first. Since calipers for a 15-year-old Volvo aren’t exactly falling off the shelves at 6:00 on a Friday evening, the 850 sat for the entire weekend. Come Monday, though, it was back on the road and, to my agreement, quiet.

For the first day, anyway. Continue reading »

Apr 082012
 

Last week I talked a little about what makes tires so important and I gave a few suggestions for enthusiasts who need a year-round performance tire.

Now that we have traction covered, it’s time to start doing something with it. I know the most popular thing to talk about would be adding power, but in reality the second most important part of driving is being able to slow down and stop. It’s not as glamorous as ripping engine sounds and neck snapping acceleration, but braking is what keeps you from wrapping yourself around a tree, making sure you can experience all those other good things more than once. That being the case, let’s take a look at what goes in to stopping a car.

Disc Brakes

Since we are talking about higher-performance applications here, I am going to focus only on cars that use disc brakes. If you car uses drums in the rear, then there really aren’t that many upgrade options for you anyway, other than to swap in a disc setup. Just make sure the drums and shoes are fresh and the wheel cylinders function properly and you should be fine.

A disc brake system is simpler than most people think. As your wheels spin, so does a big metal disc (rotor) inside each of them. When you push on the brake pedal, two pads squeeze either side of that rotor, causing the friction that slows the wheels down. Most carmakers use a compound in their pad material that is designed to create minimal dust, make no noise and still stop the car effectively. Upgrading is both simple and inexpensive.

Pads

Changing to a higher performance brake pad is the most effective upgrade you can make to the stopping system of any car. Small changes in the material and composition of the pad compound usually results in dramatic improvements in the initial bite of the pad and its resistance to fade. The trade-off is in increased cost, increased brake dust and likely some increase in noise as well, depending on what compound you choose. Since a fast car is pretty much worthless, though, if it can’t stop, it is worth the minor compromise.

I have used several pads on my cars over the last ten years or so. Some have been worth the money and some haven’t, and there are a wide array of options. While track pads offer incredible bite and very long endurance, they often require heating before they will work properly and don’t function well in a daily driver environment. The majority of drivers will want a high performance street or, for those who do occasional motorsport, a street/track compound pad. These will assure that the car can stop in any condition and shouldn’t put a large hole in a modest budget.

Of all the pads I have used, these are my favorites:

Image courtesy of TireRack.com

Hawk HPS This was one of the first pads I tried when I was first learning about cars and, though I have been through probably half a dozen others, it is still the one I keep coming back to. They feature excellent bite while still offering long life and relatively quiet operation (although I have had sets that squealed loudly when not installed with new rotors – more on that in a moment). I have found them to be an ideal option for someone like me, who drives in a spirited fashion on the street and also autocrosses occasionally. They are not the cleanest pads in the world, but if you wash your car regularly, that won’t be a major issue. They are an excellent value as well.
More information can be found at http://www.hawkperformance.com/performance/hps.php

Image courtesy of BuyBrakes.com

EBC RedStuff Though the next two pads are both from the same company, they have different strengths. The RedStuff pad from EBC seeks to be a bit more high-end. It is a high-performance compound that produces low dust and low noise as well. It is designed for heavier, high-horsepower cars, though, and may not be available for smaller, lighter applications. It is also slightly more expensive than some other offerings. However, the return for your money is impressive. EBC claims that RedStuff pads can increase braking efficiency up to 30% and my own experience with them has been highly favorable. They live up to the company’s claims of low dust and noise and the decrease in stopping distance is noticeable. They may take longer to bed in to the rotor than a softer compound, but the result is worth the patience. Mine have worn like steel as well. If you have a heavier car, this is the pad for you.
More information can be found at http://www.ebcbrakes.com/automotive/redstuff_brake_pads/index.shtml

Image courtesy of BuyBrakes.com

EBC GreenStuff Where the RedStuff pads cater to a specific audience, GreenStuff is EBC’s standard high-performance street pad for everyone else. The 2000-series, which is slightly different than the compound used for the GreenStuff truck and SUV pads, is designed for sport compact applications and what EBC calls “premium street driving.” I have found them to be competitive with the Hawk HPS above in both performance on the street and price, but the GreenStuff pads create less dust. The Hawks, though, were a little more reliable for me in an autocross environment. Your experience may vary.
More information can be found at http://www.ebcbrakes.com/automotive/greenstuff_brake_pads/greenstuff_brake_pads_2000.shtml

Rotors

To be honest, as cool as slotted, drilled and dimpled rotors look, they are not necessary for most cars. The vast majority of cars, even those that see some autocross use, don’t need the kind of serious heat dissipation that these features offer. As such, those on a budget are best off simply replacing their rotors with a solid, brand-name part. The pads will still bite as they are designed and the lack of ridges and edges on the rotor surface will go a long way to increasing your pad life as well. In the event that the rotors do warp, a solid rotor can be cut with a brake lathe, saving you money on replacement. I have had success using factory rotors with aftermarket pads for years. If you are looking for an alternative, though, Brembo also makes an excellent solid rotor at competitive pricing.

If you decide that your brakes really do have to look that cool or that heat dissipation is going to be an issue for whatever reason, I have one piece of advice for you: don’t cheap out. While you can find inexpensive drilled and/or slotted rotors on eBay and the like, you might as well go to Pep Boys, buy the crappiest rotor off the shelf and make some holes with your trusty Craftsman drill. A good pair of slotted/drilled rotors is going to be pricey, which is why I made the point I did above, but if you skimp here you will regret it later.

I don’t have specific suggestions for slotted or drilled rotors, but Powerslot, EBC, Brembo and Hawk make a variety of products and all have excellent reputations. Shop around and see what suits your needs for looks, performance and price. Just be prepared to spend a little more.

The Next Step

Another inexpensive option is adding a set of stainless steel braided brake lines. Where rubber lines expand and contract every time the pedal is pressed and the fluid is forced through them, a stainless line holds its form, allowing a more linear flow of pressure to the calipers and pads. The driver gets improved pedal feel and the brakes become more efficient. This upgrade requires that your brake system be bled, though, so it is a little more involved than simple pads and rotors. I would recommend this only be done by someone with experience or a professional.

There really is no need to go beyond any of the above changes if your car is driven on the street and doesn’t see a large amount of track time. The next step up would be a “big brake” kit. Such a system replaces the entire caliper/pad/rotor system with much bigger pieces, dedicated to high-performance stopping. Big brake kits are expensive (figure on spending over a grand for the front and again for the rear, at least) and are likely to change the dynamic of your car. They may look cool, but the investment is not worth it, in my opinion, if the car is not a track machine.

Next time: Handling