SPS

Probably the most often-asked question that we receive at SPS is, "What can I do for free to improve the performance of my Saturn?" Unfortunately, the harsh reality is that expanded performance thresholds usually involve tradeoffs in other matters. And the classic trade-off is the financial cost. Quite simply, speed costs. And it usually costs money. It is no coincidence that the Acura NSX, for example, costs more than a Civic – despite the fact that the Civic holds more passengers and luggage and gets better gas mileage. Or, perhaps more appropriately in our case, it is also no coincidence that the Corvette costs more than the SC2, despite similar advantages for the SC2.

So more often than not, the standard response to these inquiries includes phrases like, "nothing", "speed costs money", and "there is no such thing as a free lunch". And certainly, there are no strange secrets that will instantly improve your Saturn’s performance. So don’t expect to find a magical fuse that will create more power upon removal – or a gasoline additive that adds 30 HP. These things do not exist.

But there are a few things that an educated enthusiast can do to improve thresholds of vehicle performance without spending money on more parts and accessories. So the rest of this article will attempt to explore some of the legitimate and safe steps that can be taken to improve performance without spending money on new parts or permanently altering or defacing your original parts.

1. Push the Accelerator Pedal Down Further

At first glance, you probably think that this is a joke – or perhaps a "smart-ass" suggestion. But, in fact, many enthusiasts – including some within the online Saturn performance community – spend money on a particlular aftermarket gimmick that claims to do nothing more than what you can accomplish for free by literally pushing the accelerator pedal down further with your right foot.

The product to which we are referring is a gimmick known as the "Venom 400" marketed by Python Injection, Inc. The Venom 400 claims to alter closed loop fuel and spark response by replacing or modifying the voltage signals into the powertrain control module (PCM) from the manifold absolute pressure (MAP) and throttle position (TPS) sensors. Since the PCM uses input from the MAP and TPS sensors during closed loop operation to determine an appropriate fuel response, their logic behind this attempt is to trick the PCM into thinking that the throttle is open more than it actually is so that additional fuel will be added to the mixture. And since a mixture slightly richer than stoichiometric is generally best for producing peak power, the additional fuel should create some extra power (albeit far from the 25% increase that they claim).

However, it is important to remember that MAP and TPS inputs only affect PCM decisions during partial throttle driving. Once MAP and TPS signals reach voltage levels that indicate full-throttle, the PCM begins ignoring these input signals and resorts to open loop operation – at which point, additional voltage from MAP and TPS sensors will not affect fuel response. In other words, the Venom 400 claims to function only under partial throttle conditions.

This partial throttle limitation is not something that is denied by the makers of the Venom 400. In fact, they openly admit this in their marketing material. They even publish dynamometer testing results at their website (http://www.venom-performance.com/v400/dynos.html) that show power gains as a function of throttle position. If you look closely, you will notice that the Venom 400 power curve matches the stock power curve at 25% and 100% throttle openings. And, of course, on both curves, the point of maximum power occurs at a 100% throttle opening. But at all partial throttle openings between these points, they indicate a substantial increase in power by using the Venom 400.

Specifically, at 40% throttle opening with the Venom 400, as much power is indicated as was produced at 60% throttle opening on the stock curve. And at 80% throttle opening with the Venom 400, as much power is indicated as at 90% throttle opening on the stock curve. At full throttle (100% throttle opening,) the venom curve matches the stock curve – which makes sense, since the Venom only claims to function during partial throttle operation.

What they fail to mention is that the amount of throttle opening is determined by the accelerator pedal – which is controlled by the driver with his or her right foot. So by simply pushing harder on the accelerator pedal, you can open the throttle as far as you want - for free. In other words, you do not need to spend money to go faster from a partial throttle position. You need only to open the throttle further until one of two things happens: 1) the car goes as fast as you want or 2) you reach full throttle and cannot push the pedal any further (at which point, the Venom 400 is useless since it only functions during partial throttle operation).

So our advice is this: if you want your car to produce the power of a 60% throttle opening, just push harder on the accelerator pedal until the throttle is open 60%. And if you want your car to produce the power of a 90% throttle opening, just push harder on the accelerator pedal until the throttle is open 90%. And if you want even more power than that, push the pedal to the floor so that the throttle is open 100%.

This method does not cost anything, yet it accomplishes the same increase in power as Python Injection claims to deliver with the Venom 400.

2. Remove Mass

If you want to make a single modification to your car that improves all elements of vehicle performance – forward acceleration, cornering, and braking – then reducing the mass (or weight) of the vehicle is the clear answer. Why? Because F=MA or Force = Mass x Acceleration. So if you want lots of acceleration, you either need more force or less mass.

We can increase force in a number of ways – such as enhancing the engine’s output to create more power, or by enhancing tire traction through suspension tweaks. But changes to any one of these areas will only affect a partial list of the elements of performance. (A more powerful motor will not help cornering or braking, and an enhanced suspension will not help forward acceleration.)

A reduction in mass, on the other hand, will improve all areas of performance simultaneously. And in some cases, it won’t cost you a penny.

You don’t believe it? Perhaps an example will prove it. Consider the effect upon the power-to-weight ratio – which has a great effect upon the rate of forward acceleration – within the framework of two potential changes:

1. The addition of 6HP from a Powerstack intake or
2. The reduction of vehicle mass.

To begin this evaluation, we must first establish some assumptions.

Assumption #1: the beginning vehicle weight is 2400 lbs.
Assumption #2: the stock power output is 124HP.
Assumption #3: a Powerstack adds roughly 6HP.

If these assumption are true, then the stock power to weight ratio is 124HP/2400lbs=.05167HP/lb. (Remember, more power per pound is better. So you want the ratio to be a larger number. Although it is more common to measure pounds per horsepower, because we refer to the ratio as the "power to weight ratio," we have measured the ratio in this example as horsepower per pound for the sake of simplicity.)

If we add a Powerstack intake and gain 6HP, then the power output increases to 130HP (124+6=130) and the power-to-weight ratio climbs to 130HP/2400lbs=.05417HP/lb.

So what weight would the vehicle need to be in order to achieve the same .05417HP/lb. ratio without the Powerstack? 124HP/.05417HP/lb=2289lbs.

In other words, if you can lose 111 lbs. (2400-2289=111) of vehicle mass, then you will enjoy the same increase in forward acceleration as you would by installing a Powerstack. And as a bonus, you simultaneously receive a similar improvement in both cornering and braking!

So now the question becomes, "how can you loose 111 lbs. of mass for free?" Here are some possibilities:

1. Remove the stereo. Hey, we like music too. But you might consider listening in your living room instead of your car, because your aftermarket stereo equipment is probably weighing you down. By the time you add up the weight of subwoofers, enclosures, amps, speakers, head units, and who knows what else, you can easily add 75 lbs. to your mass. (Perhaps twice that depending on the enclosures and the subs.) Move it all to the living room, or sell it and use the cash to buy parts. Savings from stereo removal: 75 lbs. Total Savings: 75 lbs.

2. Ditch the 17-inch chrome wheels. Big wheels look cool. And they might even help you attract attention from girls. But they are weighing you down too. The stock 15-inch Saturn alloy wheel weighs around 16 lbs. According to Enkei’s website  {http://www.enkei.com), the 17-inch chrome Spider3 weighs 30 lbs. The difference of 14 lbs. (30-16=14) added to each corner creates 56 lbs. (14x4=56) of additional weight. (And to make matters worse, this extra mass is rotating and unsprung!) Sell the chrome wheels and use the money to buy some sticky tires for your stock wheels. Or better yet, choose a lightweight 15-inch wheel that offers a weight reduction from stock and a more aggressive offset for a wider track width and more tire clearance. Savings from chrome wheel removal: 56 lbs. Total Savings: 131 lbs.

3. Lose the body kit. Fiberglass and urethane don’t weigh a lot – but then again, they don’t make you any faster either. And an extra 30 lbs. here and there makes a difference when added together. If you want your car to look better, try washing it once in awhile. Savings from body kit removal: 30 lbs. Total Savings: 161 lbs.

4. Diet and Exercise. Most of us have gained a few pounds since high school – some of us more than others. Well guess what: unless some skinny guy is driving your car while you watch – or you’re carrying an extra 10 lbs. of driving skill around your waist – then you’re weighing yourself down. Losing the extra weight will not only improve vehicle performance, but you might feel better and live longer too. Savings from healthier driver: 10 lbs. (maybe more) Total Savings: 171 lbs.

A total savings of 171 lbs. results in a new vehicle mass of 2229 lbs. (2400-171=2229) which results in a new power to weight ratio of 124HP/2229lbs.=.05563HP/lb. How much extra power would you have needed at 2400 lbs. to achieve the same ratio? 2400*.05563=135.9. Your 171 lb. weight reduction is equivalent to an extra 12HP! (Now imagine what would happen if you added power and reduced mass…)

3. Performance Alignment

Admittedly, for most of us, an alignment is not really "free." Most of us must pay a service facility to perform our alignments. And even if you happen to own your own alignment rack, you probably paid at least $25,000 for it when it was new – which is a lot of money to tie-up in a single piece of equipment.

But even though there is probably a cost associated with performing an alignment, there are times that a new alignment becomes necessary and simply must be performed. This is true any time that struts, springs, knuckles, or front sway bars are removed or disconnected from your "S" series Saturn – or perhaps on the occasion that you ran over the curb trying to get a better look at the chic in the tank-top that was standing at the bus stop. So the point is this: if you must pay for an alignment anyway, then you might as well choose alignment specifications that will improve cornering ability. So even though the alignment service itself may not be free, specifying particular settings for improved cornering costs nothing extra. So in this case, making the right decision about alignment specs is free.

The most important alignment setting for improved cornering grip is the camber – the measure of the amount of tire lean when the vehicle is at rest. Zero camber indicates that the tire is straight with no lean to either side. Negative camber indicates that the top of the tire leans inward, causing the tire to rest against the road surface along the inside edge of the tire. And positive camber indicates that the top of the tire leans outward, causing the tire to rest against the road surface along the outside edge of the tire.

During a cornering maneuver, weight shifts to the outside edge of the car - creating body roll. As the body of the car rolls – or leans – the tires are forced to lean along with the rest of the vehicle. If the tires were originally positioned at zero camber, then the body roll forces the tires of the outside edge of the car to roll into a positive camber position. As this happens, the amount of tire contact with the road surface decreases – causing a traction loss.

Negative camber can be used to prevent this effect during body roll. By positioning the wheel into a negative camber position when at rest, it will tend to lean into a straight position during body roll. This allows the tire contact patch to be as large as possible (for maximum traction) just when you need it most - when large cornering forces induce body roll.

Most alignment shops tend to target conservative neutral factory specifications when performing an alignment. This usually results in zero camber – or very small amounts of negative camber that may not be enough to provide a traction advantage during aggressive driving. To increase the performance advantage of your next alignment, specify greater amounts of negative camber. For aggressive street driving with the occasional autocross or track event, target 1.5 degrees negative at each corner. For a more aggressive set-up, target 2.0 degrees negative.

Just remember that additional negative camber forces the tires to roll along their inside edge during normal driving. This is likely to promote uneven tire wear. Negative camber also moves the top of the tire toward the strut. So if tire size and wheel offset have limited your tire clearance with the strut, then wheel spacers may be needed to allow enough room for additional negative camber.

4. Adjust Tire Pressure

Tire traction with the road surface is the single most important element of cornering and braking performance. And most chassis modifications – including tire and wheel selection and suspension tweaks – are truly just intended to maximize tire traction (or at least minimize traction losses). So it should come as no surprise that varying tire pressures – which will affect tire traction – will have important effects upon vehicle handling. And as long as you have access to a free source of compressed air and a tire pressure gauge, changing and experimenting with tire pressures to achieve improved handling characteristics is free!

Unfortunately, there is no set of universal tire pressure specifications that will maximize tire traction when used with all tires in all conditions. So experimentation will be necessary to calculate the correct pressures for your particular combination of vehicle, tire, and application. However, the goal of your quest should be to find the amount of pressure that maintains as flat of contact patch as possible while simultaneously preventing compliance within the tire sidewall.

In other words, consider the effects of the two extremes of tire pressures. Too little pressure allows the tire sidewall to flex and roll – hence allowing compliance within the tire. This compliance can create unpredictable vehicle movements and allow the workload of the tire to be shifted to just one edge of the tire tread. But as the workload shifts to a smaller section of the tire tread, the amount of work that the tire can handle is reduced. This leads to faster tire saturation and a loss of traction. And conversely, too much tire pressure forces the tire to stand up very straight until it rides only in the center section of the available tread. And the reduction in the contact patch with the road surface creates an obvious traction loss.

Therefore, the goal of tire pressure strategy is to identify a pressure between these extremes. The ideal pressure minimizes tire compliance while maximizing the size of the tread contact patch with the road surface.

So how do you find this balance? In most cases, it is a matter of trial and error in which one sets pressures, test drives the car, and documents the results. In many cases, the results are determined by considering driver feedback as to whether the car handled better at the higher pressure or the lower pressure.

However, a very useful tool for determining the effectiveness of a pressure setting is a tire pyrometer that measures tire temperatures. With a pyrometer, one can measure temperatures of the tires immediately after a driving session. By measuring the temperatures in three locations – inside, center, and outside - of the tread surface, one can determine if under-inflation or over-inflation was present during the test. If the center temperature is considerably higher than the edges, then it probably indicates over-inflation that caused the center of the tread to do more of the work. If the temperature of either of the edges is considerably higher than the center, then it probably indicates under-inflation that allowed load shifts to a tire edge due to tire compliance – thus causing the edges of the tire to do more of the work. If temperatures in all three locations are close, then the workload is being evenly distributed along the surface of the tire – thus indicating the perfect pressure.

5. Bleed the Brake System

When you push on the brake pedal, does it feel mushy – as though lots of pedal travel is required to achieve enough clamping force to stop the car? Does the brake pedal seem vague and inconsistent during stops? This is a common problem on many cars – especially those that have seen some use. But when the brake pedal no longer offers a firm feel and consistent feedback, it becomes very difficult to brake effectively in a high speed or competitive environment. Often, the mushy pedal and inconsistent feedback make it difficult to gauge the point of lockup. And the initial delay in the beginning range of the pedal travel can be unnerving – often causing the driver to react through a sudden burst of additional pedal application that can disrupt the vehicle under braking.

For these reasons, a performance car should have a firm, responsive, and consistent brake pedal that effectively communicates between the brake corners and the driver.

There are many factors that contribute to a mushy and vague pedal. These include brake pads that have tapered during use, rubber brake lines that expand outward as pressure increases within the brake pipes, and compliance that was designed into the stock system due to cost constraints. Unfortunately, these causes generally cost money to fix by buying new brake pads and braided stainless brake lines – or by redesigning the entire system (in the case of design-related compliance).

But there is one potential cause that costs almost nothing to fix: vapor within the brake line system.

Brake fluid is designed to be insensitive to temperature changes. This allows the brakes to function properly when they are very cold as well as very hot. However, the formulation that allows brake fluid to be resistant to temperature extremes also tends to allow the fluid to absorb moisture from the atmosphere. Over time, so much moisture is eventually absorbed into the fluid that the boiling point of the fluid becomes quite low, thus allowing the fluid to boil when the brakes become hot during repetitive hard stopping. When the fluid boils, it releases vapor within the brake lines. And, unlike a liquid, a constant volume of vapor can be compressed to occupy a smaller space. And the compressible quality of vapor creates a mushy and vague feel when present within the lines. (When vapor is present within the system, then applying the brake pedal merely compresses the vapor instead of hydraulically actuating the brake caliper piston.)

Fortunately, there is virtually no cost associated with removing the vapor. It merely involves a service procedure known as "bleeding" the brake system. Bleeding the brakes is a simple process in which vapor is carefully removed from the lines and replaced with fresh, clean brake fluid. (Unfortunately, it does cost money to buy fresh clean brake fluid. But it is doesn’t cost much – and it is worth every penny.)

For a detailed step-by-step set of instructions for how to properly bleed the brakes on a Saturn, please see SPS’ October technical article entitled, How to Bleed Brakes The Right Way.

6. Improve the Driver

It has happened twice now – first at an SPC track event at Gingerman, and then again at the 2^nd annual Hikari Racing school at Putnam. I was driving my newly-purchased 97 SC2 showroom stock C racecar – the same car driven by James Walker and Mark Rushbrook of the scR motorsports race team in national SCCA competition – and I was starting to feel confident and fast. Then all of a sudden, James Walker chased me down and passed me – with ease. Then Mark did the same thing.

They must have been driving really fast cars, right? Wrong! James was driving his wife’s completely stock SL2 commuter car and Mark was driving his own stock SC2 daily driver – both with street tires!

Clearly, I was driving a faster and thoroughly well-prepared car. In fact, Mark used the same car the next week to win one of his regional championships. So the weak link was not the car. The cold hard reality is that James and Mark are significantly better drivers than me – despite the fact that I have years of SCCA solo2 experience and previous road course experience. In other words, the weak link was me, the driver.

And as any wise enthusiast knows, the best place to gain a performance advantage is by identifying and improving the weakest link within the system. So be honest with yourself: are your driving skills the real weak link to performance in your car? And if so, are you making a serious effort to improve your driving skills and to become familiar with the physics of vehicle handling (or have you spent more of your time debating moot points on an internet message forum?)

If the latter is true, then the weakest link on your car may be the driver. Unfortunately, improving the driver is not always free – as evidenced by several $150-per-day driving schools that I have personally attended in the past few years. And admittedly, if you decide to improve your driving skills at speed, on a real racetrack, with the help of an instructor, then be prepared to spend some money. Most lapping days cost around $150 per day plus travel expenses. And the more intense schools can cost between $500 and $2000.

But there are significantly less expensive alternatives. For example, if you are a novice driver and are just beginning to ponder the importance of performance driving techniques, then consider how much better your driving could become with just some basic information and a little practice. So if you want to get faster for free, we suggest reading as much information as you can find about car control, driving technique, and vehicle dynamics, and then applying and practicing what you learn in everyday driving on the street. Are we suggesting racing on the street? Obviously not! But you can easily practice using the proper "racing" line through turns and corners – even if you are traveling at legal speeds. And you can condition yourself to use the proper seating position and grip upon the steering wheel. And you can practice looking further ahead and applying smooth driver inputs. Not only will practicing these techniques make your commute a bit more fun, but it is sure to improve your high-speed road-course skills too.

So where can one get some basic information about driving technique? Your local library probably has several books that outline high-performance driving techniques. By borrowing one or more of these books and reading them thoroughly, you will probably be able to learn the basics of car control in a variety of situations.

There are also a few sites on the internet that discuss high speed driving techniques. A brief Yahoo search for this article uncovered http://homepages.which.net/~kendrick/drivingarticles4.html, which offers some very limited insight into the proper road-course driving techniques, and http://members.home.net/phor, which offers a selection of articles with a focus upon the laws of physics as they apply to driving technique and vehicle handling. (Please note: we cannot speak for the accuracy of the content within the above articles.) The SPS site also offers a detailed look into a driver’s school/lapping event that took place at the Putnam Park Road Course in 1998. This article can be found here.

Once you have read a few things and begun conditioning yourself for the proper driver basics, then you will probably get anxious to start exploring the limits. Rather than exploring these limits on the street where your chances of damaging property and injuring others is quite high, consider the inexpensive venue of an autocross. Put simply, an autocross is a vehicle handling course, usually created with cones in a large parking lot, that tests driver skill and vehicle handling through timed competitive laps. The goal is to complete a single lap as quickly as possible in a race against the clock. There are no speed limits – you are encouraged to drive as quickly as your skills and your car allow. Which makes it a great place to legally explore the limits of both you and your vehicle. In most cases, entry fees for an autocross event are only $25 or less. And not only is an autocross a lot of fun, but it also exposes you to other drivers – many of which are anxious to share their knowledge and experience for free.

For more information about where to find autocross events, high-speed lapping events, or driver schools in your area, we suggest the following organizations:

1. The Sports Car Club of America (SCCA) http://www.scca.org
   
2. Saturn Performance Club (SPC) http://www.saturnperformanceclub.com
3. The BMW Car Club of America (BMW CCA) http://www.bmwcca.org
4. Porsche Club of America (PCA) http://www.pca.org
5. Corvette Club of America (CCA) http://www.corvetteclubofamerica.org

(Even though you may not own a Porsche, BMW, or Corvette, most of these clubs will still allow you to participate in their lapping days and autocross events, if you ask nicely and pay the required entry fee.)

In Summary…

At the beginning of this article, we promised to identify some areas of enhanced vehicle performance that can be tapped for free – or at least without spending money on additional parts and accessories. But we also warned you in advance that there is no "magical" solution. In fact, many of our suggestions require additional investigation, work, and sacrifice.

We expect that some readers may be angered or offended by some of these suggestions. So please understand: we do not think negatively about you, your friends, relatives, or associates just because you have a big car stereo or because you could stand to loose a few pounds around your waist. We do not plan to judge your character by the wheels on your car or the pressures at which you set your tires. And we will not dislike you if you choose to spend time on the internet instead of participating in an autocross or driver’s school.

But it is important to recognize that these areas and these types of suggestions do play a real role in vehicle performance. And, ironically, many of the enthusiasts that inquire about free performance possibilities are the same ones that enjoy heavy stereo equipment, big chrome wheels, and spending time at internet message forums. And while these enthusiasts have the best intentions, they are often simply not aware of the possibilities within their reach or the performance tradeoffs that they endure as a result of certain decisions. Rather than being threatened by additional information, we hope that Saturn performance enthusiasts can digest this information and make wiser informed decisions within the framework of their performance objectives.

And if doing without the stereo, going on a diet, or taking responsibility for becoming a better driver seems like too much effort and sacrifice, then it only goes to show that there is no such thing as a free lunch. Performance often results in other costs – financial or otherwise. How fast do you want to go?