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FWD Racing Tips

Discussion in 'Motorsports' started by zk0729, May 17, 2016.

  1. zk0729

    zk0729 Well-Known Member

    I have no problems with this being removed if need be, but i didn't happen to see any posts on the subject directly, so I thought I'd make one. This will mostly cover the differences between RWD and FWD setups, and how to make the most of your butt-dragger.

    First and foremost you must understand that FWD and RWD are staggeringly different platforms. This creates entirely different needs for the suspensions and very different driving styles for both.

    For this read, you'll need to know the meanings of "oversteer", "understeer", and "snap oversteer". I'll try to cover it as well as I can.

    To understand those, you'll have to understand traction. Traction is, in short, the ability of the tires to transfer energy to the road. Traction is used for three things, accelerating, braking, and steering. If you ask too much of your tires all at once, you probably wont get anything at all. Should you decide to slam on the brakes and turn the wheel at the same time for instance, your vehicle wont be able to do either efficiently.

    Now, oversteer is when the vehicle tries to turn further than you told it to. For the sake of the explanation and it's effects on racing, this is usually when the rear tires begin to spin around and try to throw themselves forward. Since this is seldom an issue on basic FWD setups, I'll leave it at that.

    Snap-oversteer is when the vehicle load shifts from the rear of the vehicle shifts to the front from lifting off the throttle, and can cause you to lose control of the vehicle. To save more time, you won't really be seeing this in a Celica, so we'll skip over that for now also.

    Understeer is one of the most pertinent issues with a FWD, and it is when the car doesn't turn as far as the wheels (steering input) tell it to. Part of the reason this is such an issue with FWD and especially open diff FWDs is that the front tires are asked to do almost all of the work for the vehicle. The front tires are made to turn, take braking load, and pull the car all at once. If you've ever taken a hard turn and had one of your front tires start spinning (assuming you're reading this, you don't have a LSD), that is due to your open diff. What happens is that one tire begins to spin, causing the whole system to lose available traction. There are many courses on youtube covering differentials, which explain it more in depth.

    So you may ask yourself, what am I to do with one tire fire and an uncooperative front end if that's an issue with FWD? Do I give up and invest in something else? Well I've got good news, people have been at this for a long time. Here are the biggest keys to getting the most out of your FWD,

    Buy good tires
    Learn to drive

    Of course there are a myriad of modifications you can make to improve handling, nothing will show you the limits of your vehicle like your tires, and the mirror.

    (I'll keep posting to this thread as I have time)
     
  2. zk0729

    zk0729 Well-Known Member

    Some Important Keywords

    While eventually you'll find yourself throwing convention to the wind and feeling the movement of the car and responding accordingly, there are are some good thoughts to get you started. Here are some of my own.

    Release the gas to swing the ass
    Punching the throttle isn't going to do you any favors in a corner with a fwd. You're not going to kick out the rear and drift it, at best you'll keep just enough traction to keep from slamming into the wall (or a defenseless cone, shame on you). The best way to prep for the apex is to release the gas and get your front end aligned for a cannon shot to the next pass. I assume at the very least you understand what an apex is and how to handle one, so if not I'll leave that to you to find out on your own initiative.

    Brakes aren't your friend
    Now, for god's sake please use your own judgement on this one. Don't be slamming into a wall or car at full speed and saying "he told me to". Assuming you have common sense, you should try to use your brakes as little as possible. This is more of a general rule than anything, and when you get to more advanced techniques this actually gets thrown out the window. But for now, try to learn the way your car behaves. If you have to stand on the brake to slow down for a turn, you're loosing valuable traction.

    Slow down to go faster
    I know that doesn't make much sense out of context, especially if this is your first time, but you're not going anywhere fast if you barrel into a wall or car while driving a course. Typically speaking, you're going to see a better time by following a better line continuously than missing the entire apex and losing more speed to save yourself. Plus, if you follow a better line, you're less likely to leave yourself completely open to being passed, so it's a win win!

    Keep your eyes on the road
    You'll go where you're looking to go. At all times, keep your eyes directly on the road, and any other vehicle around you should only get a quick glance. Naturally don't go barrelling sideways into someone, but your focus should always be on where you want your car to be. If you keep staring down that cone you always clip, you're always going to clip it. Trace the line you want to follow with your eyes and keep yourself in line with it, don't try to follow the line with your hands and glance at it after the fact.

    You don't need every gear
    Most of the time, you're not going to be shifting that often, believe it or not. While it's all based on judgment, keep in mind that if you're upshifting and losing power when the other person doesn't have to, you're going to wind up getting passed. Autocross is not an easy task for your car, you can't be gentle on it. Most of your power is going to be made high up in your powerband, so that's where you need to try and keep it

    Other than that, keep your chin up and keep your eyes forward. You win some, you lose some. Things will break, things will break in the worst possible time and place. It happens. Everything you do crafts you into a better driver, so never consider a loss a failure.
     
  3. zk0729

    zk0729 Well-Known Member

    It's a Four Corner Effort

    As with the dynamics of any four-wheeled vehicle, FWD, RWD, or AWD, all four corners of the vehicle make a huge impact on the way the vehicles drive. In order to understand how to make proper modifications, you need to understand how the dynamics of the movements work. Basically, everything you do creates an opposite motion. Newton's third law right? Makes sense. So, if you brake, your weight shifts forward, if you accelerate, it shifts backward, and if you turn left it will shift right and vise versa. Why is this important, you may ask. Well, because of these opposing motions your car has the potential to make an opposite reaction than what you wanted, or expected. Remember the understeer and oversteer things we talked about? Well we're gonna revisit that here.

    Sway bars and stiffness
    Keep in mind that in a fwd, your front tires need most of the traction in order to stay planted and keep from spinning. In a RWD or AWD, you need to keep traction on all four tires in order to maintain a proper balance. To try and explain this as best as I can using only text, a RWD needs to maintain an overall flat posture in order to stay balanced and counter oversteer and roll issues. A fwd, on the contrary, needs to be able to put its weight on the outside front to keep it planted.

    Based on this, think about what we just said regarding opposite motions. Should you decide to punch it while turning right, your weight will shift backward and you'll also put more strain on the tires, making it more likely to spin the tire and wind up doing neither. So, say you're turning right, physics does most of the work for you, and shifts the weight to the outside left. While in a rwd, you don't want to put the weight on the front tire, as it removes traction from the rear, that is exactly what you want to do in a FWD. best way to do this? keep the rear stiffer than the front. As crazy as it sounds, remove the front swaybar to do this. On the road you'll be losing a sizeable amount of comfort, but it allows the front end to shift further and achieve a better bite, and allow the rear to keep the front end on track. it also lets most of the weight go to the outside, where its needed to pull the car around. As we covered before, you shouldn't punch it while taking a corner before crossing the apex, or you'll wind up slipping and not turning or accelerating.

    Without removing the swaybar, it will be actively trying to keep the car level, putting applicable force in the wrong position, making it more prone to sliding.

    Now, think about the best way to angle the front end to continue moving. Think of it like a pool cue. If you were to try and adjust it from the front, you'll likely miss your target because you'll be requiring the front to do both large and small adjustments at the same time. However, if you rotate the rear of the cue, you can turn a very broad motion into a very fine one. And how did we say you could do this in a FWD? for those of you skipping ahead, you release the gas. Notice how all of those wonderful things work together? Releasing the gas allows you to shift the weight forward and in so doing makes it easier for the rear to slide, AND you give the front more traction! Isn't it great how these things fit together!?
     
    Last edited: May 17, 2016
  4. zk0729

    zk0729 Well-Known Member

    Back to Basics

    Before going any further, I wanted to go ahead and cover most of the basic terms you'll encounter when auto-crossing, and try to cover anything else we might bring up in the thread. So, while more specific information will come later, here are some terms you may need to know.
    If you didn't know these terms your first time around, I recommend re reading what i just said.

    Apex
    The apex of a curve is the point where you've passed the entry point and have entered the exit point. Without a visual explanation the best way I can describe it is that it is the "peak" of the turn. During a curve the apex will be the point where you begin to accelerate your way out of the curve

    Swaybar/Anti-roll bar
    This is the part of your suspension that helps reduce body roll. It is essentially a torsion bar that connects the two wheels with end links on either side. Basically it creates tension that adds lateral stiffness to your movements.

    Spring
    This one is pretty self explanatory, but it is the heavy metal coil part of the suspension. It works to absorb the impact as you travel over rough terrain (essentially, fill in the holes in the road and push the tire to the ground). By itself, it would actually compress over bumps and launch you upward after compressing. Obviously this would be a serious problem, so they are used in conjunction with dampeners to absorb the impact and maintain a vertical rigidity.

    Strut
    The inner part of your suspension, that goes inside your spring. There are hundreds of different suspension setups. but that is the case with the Celica. It absorbs some of the impact and dampens the force of the spring on extension and compression. To try and keep it simple, it turns the kinetic energy into other energy.

    McPherson
    This is the type of suspension used by the Celica. It is designated by using the top of the strut as a pivot point for the wheel. Basically the lower pivot is your lower ball joint, while the top pivot is your strut. While this simplifies things, it also has it's drawbacks, but there's not really anything we can do about the type of suspension we have.

    Double wishbone/SLA (short/long arm)/ULA (Upper/Lower Arm)
    This is a different type of suspension. It uses an upper and lower ball joint to control the pivot of the wheel, and has a strut/spring setup that connects to the lower control arm from the frame. These have very unique characteristics because of the design, but I'll leave that to you to research (hint, they use it on the MKIII Supra)

    FWD
    Okay, we should all know our drivetrain types, but I'll cover my bases. FWD is Front-Wheel Drive, which is where the front wheels are used to propel the car forward. These usually use transverse engine configurations, and use two CV axles (usually) to power the front wheels from the differential.

    RWD
    RWD is Rear-Wheel Drive. It means that the vehicle uses the rear wheels to push the vehicle forward. Typically this is done using a driveshaft coming from the transmission going to the rear wheels using a rear axle and separate rear diff, but you'll never really have to worry about that with a ST162 or later.

    AWD
    This means that the vehicle uses all four wheels to propel the vehicle forward. While there are many advantages to this, one of the biggest drawbacks is weight. However most people consider this to be negligible, as the grip improvements make a HUGE difference in track times and performance.

    FF
    This is used to denote Front engine, Front-wheel drive. It means that the engine sits in the front of the car, under the "hood", and propels the car forward using the front wheels.

    FR
    This denotes Front engine, Rear-wheel drive. It means that the engine sits in the front, and sends power to the rear to propel the car forward

    MR
    This is used to designate Mid-engine, Rear-wheel drive. This means that the engine sits between the front and rear axles (usually toward the rear, but not necessarily) and uses the rear wheels to drive the engine forward.

    4WS
    This is an interesting one, this means "Four-wheel steering", and means that the vehicle, when turning, uses the front two wheels to turn one way, and the rear wheels turn in the opposite direction to turn even faster. These use complicated systems, but it is relevant to know for ST183 owners.

    Transverse
    This means that the engine sits facing left-right in the car (the timing belt points toward the side)

    Longitudinal
    This means that the engine sits front-back in the car (the timing belt points toward the nose)

    Forced Induction
    This means that the vehicle uses air that is greater than atmospheric pressure in the engine. The amount is usually designated by PSI in the US, and BAR everywhere else. We'll cover Superchargers and Turbochargers at some other point.

    Natural Aspiration
    This is basically just not forced induction. Getting into the specifics leaves the point of this part of the forum, just know that its as linear and reliable as you can get. Everything that is not otherwise specified will be circumstances in which the car is naturally aspirated.

    Body Roll
    This refers to when the top of the vehicle swings left/right from perpendicular with the ground. It's a little hard to get any more specific than that.

    Pitch
    This is the movement of the car forward/backward on the suspension. So as you brake, it goes forward, and as you accelerate it goes backward.

    Camber/Caster/Toe
    This will be covered as necessary the first time it comes up. Sadly there is no easy way for me to describe these without using images here.

    CV (constant velocity) Axle
    Okay, so, we're definitely leaving the realm of just driving info here, but I'll throw you a bone if you're curious. A CV axle is one that has the input and output spinning at the same speed. In this case, the output is the tires, and the input is the differential. The reason a driveshaft isn't a CV axle, is because it is going to a differential that uses it's own gearset to power the tires, making the transmission output different from the tire output. It's also possible (although uncommon) to have hubs that use gearsets that change the output from the transmission at the actual wheel, but you won't have to worry about that in your Celica, anyway.

    Any further information will be placed with the applicable information, so some of this may show up again, and I may add to it if I need to.
     
    Last edited: May 18, 2016
  5. eNtraxGT88

    eNtraxGT88 Well-Known Member Donated!

    Just a couple things to add.

    For swaybars, it's very good as an alternative to change to a thick rear bar while keeping the stock one up front. Both this and the removing front bar trick are street-class legal, however adding a rear bar might increase the overall grip levels. Keep in mind, swaybars are settings. You can adjust body roll by thickness, manipulate oversteer/understeer tendencies with thickness difference from both ends of the car.
    Side note: releasing the throttle mid-turn will also bring the weight to the front and less in the rear to allow the chassis to rotate.

    For braking, I tend to differ from that. I want to be all out until the very last second. Brake *hard* to minimize the time not accelerating just before a corner. The trick is to be able to do this in as short distance as possible while the car is still straight before entering the turn. Brake not enough and you'll understeer through the turn. Brake too much and you lose a lot of time. Brake too late into the turn and you're asking the tires to do two things at once. But if you do it right, you will have been going the fastest before you started braking, minimize deceleration time, got yourself ready for acceleration around/exiting a corner.

    Throttle while turning:
    While beginning to learn how to drive hard, your braking should be completely done before the turn. Unless you are trail braking or left foot braking, this should be the goal. When the turn starts, you should be already on the throttle to either maintain the chassis dynamics (more throttle to understeer, less to oversteer) to micromanage a long sweeper, or a decreasing radius turn. This also preps you to accelerate coming out of the turn.
     
  6. zk0729

    zk0729 Well-Known Member

    Thanks for the input! Feel free to add any at any time, I hope to get as much info in here as we can. I was going to continue on swaybars here soon with the rest of the suspension but that just saved me time [emoji14]

    Sent from my SM-S820L using Tapatalk
     
  7. zk0729

    zk0729 Well-Known Member

    It's Time to Stop

    Oh boy. Brakes. Not one of my favorite topics to cover.

    Let me open with this, you SHOULD NOT put yourself in ANY situation where you put yourself in an extreme risk of crashing. If you're under the impression you'll be coming in too hot, SLOW DOWN. You can't win a race if you're dead. Now, that being said, lets get started.

    Now, first and foremost, let me elaborate on what I said before. Starting out, you should focus on learning how your car behaves. Typically I'd say start by using your brakes as little as possible, but as aforementioned as you get more confident with how your car brakes and slows down you actually start using your brakes as a way to accelerate as hard as you can before slowing down in the corner, but I cant stress enough how important safety is. You're not driving a Porsche, the Celica is NOT going to be able to stop on ANY kind of dime with stock brakes. There are many, many writeups on all kinds of brake kits, and I recommend doing research to find what setup is best for you. Now, moving along, here is some info

    Brakes get hot

    The autocrossing world is a harsh existence for brakes. Multiple, continuous stops from high speed lead to quick heat buildup, which can cause warping in the rotor, brake fade, and overall hinder your braking ability. Know that the harder and more frequently you stop, the less braking ability you have over time. Just like tires, brakes are one of the most important parts of your setup, for both time and safety. Because of this, your advance auto parts wearever brake setups aren't going to get you very far in the autox world. In all likelihood, you're not going to drop a ton of cash on a brake kit out the door. You'll need to start with a good set of reliable and strong rotors and pads. I won't get into that here, there are plenty of threads in other parts of the forum (and elsewhere online) to research your brake setup.

    Put your right foot in...

    An imperative technique to learn is to be able to use your heel and toe simultaneously to direct the gas and brake while your left foot does the clutch work. If you drive an automatic, you can ignore this section. But being able to boop the brakes while downshifting is one of those key things that can help you shave just a few seconds off a time. It's not something I can teach you in text alone, but i highly recommend searching "heel toe braking" on youtube or some such to give yourself at least an idea of what I'm talking about.

    Take your right foot out...

    Now this bit is even harder to explain. For us manual drivers, this may be a little more complicated. For you automatic drivers, you have no excuse. One of the things you need to learn how to do use use your left foot to brake.
    "Why? didn't you say you can't accelerate, brake and steer at the same time? Doesn't that mean it doesn't matter?" Well, no. Not even close. Keep in mind that weight transfer is extremely important when cornering, and keep in mind that we do that by accelerating and braking to change the pitch. So in a fwd especially, being able to flick the rear can allow you to make finite adjustments during a turn (remember the pool cue). The best way to do this is to take weight off of it. It's not something easily explained in theory, but it's something easily felt. Also, keep in mind as you learn to use your left foot to LIGHTLY tap the brake, your brain will translate it into "SLAM THAT SON BITCH", and don't let that discourage you. Practice makes perfect, and you can only learn by making mistakes. I can't learn anything for you, so I have to wish you luck in that regard.

    Don't Overstop

    Believe it or not, you can pick too much brake for your setup. While technically you can adjust to anything, the fact is that a stupid large brake setup can put you in as much danger as one that is too small. With only so much traction available, your six pot Brembo's just locked up all four tires, sending you skidding way off course. Basically, pick something well balanced. An overly large brake setup can cost you weight, money, and wheel spacing you didn't really need. I'm sure I'm going to get some differing opinions on that, but you need to find out what kind of stop you need for what you're doing, no two drivers are the same.

    Ceramic? Pot?

    Some of the terms used to describe brakes can be confusing for the layman who hasn't been involved before. Here are some terms you may need to know

    • Semi-Metallic - these are pads that are made of metal shards and shavings (usually steel) held together with resin. These are usually the cheapest pad option, and pretty much what you're going to see on most modern cars.
    • Ceramic - these are pads made of dense ceramic material (you know that semester of pottery you took in middle school?) laden with copper fibers. These provide far better heat dispersion than semi-metallic, and kick off much less dust
    • "Pot" - this refers to the number of hydraulic pistons on a brake caliper. Typically speaking, the more you have, the faster you stop, however size makes a huge difference. Our FWD Celica's use single pot brakes for the front and rear, and they are abysmal.
    • Drilled/slotted - This refers to the face of the rotor. A slotted surface provides better heat dissipation and better bite than a standard smooth surface. Cross-drilled rotors typically help dissipate heat, but are prone to cracking under high temperature. I recommend using slotted, non-cross-drilled rotors, but make your own decisions in what you spend your money on.

    There's no way for me to cover every piece of vocabulary you'll need to pick your upgraded brake kit, but this isn't quite the place anyway. But I hope at the very least you've seen that it isn't all about what the most expensive kit out there is, or that you have to stick with what you came with.
     
    Last edited: May 18, 2016
  8. zk0729

    zk0729 Well-Known Member

    It's Time to Start

    One of the biggest hurdles you can face is actually getting into it in the first place. I can't possibly list every single location in the US, much less the world that you can go autocross. So, the easiest thing to do (given we live in the 21st century) is to start exploring on Facebook. I'm sure there are dozens of pages just for your local area full of conversation about autocrossing, car parts, etc. Keep an eye out and start talking to people. Especially when getting started, you can be intimidated by what seems like a huge wealth of knowledge that's all above your head. Well, that's because there's a huge wealth of knowledge that's probably all above your head, BUT we've all been there. Some of the nicest and most helpful people you'll meet are found around a series of cones.

    Now, one of the best things about autocross is that it requires absolutely no prior experience or special equipment to start. Pick up a helmet, throw on your shoes and get out there! Autocrossing is set up into classes, and it doesn't matter what you're driving, there's a class for that. Now, keep in mind, the more modifications you do, the higher the class you'll wind up. So try not to throw parts at your car that you don't even know how to use, you'll wind up being way over your head.

    For convertible people, I have some bad/moderate news. You're probably going to be required to have at least a roll bar installed. I'd start with asking for a set of regulations and rules from your local events, because they vary widely. Anything from no roof required to a full through-dash cage. But dont start hacking and welding without knowing what you need first.

    Something to keep in mind is that if you plan on doing whatever it takes to win, you're going to be thrashing your vehicle harder than it's been thrashed before. So I don't recommend taking your $500 daily to the event and plan for it to hold up and continue to take you to work without at least major maintenance. Just like with anything, prep time is key. If you need maintenance parts and you know it, I highly recommend sitting any events out until it's addressed.

    All that being said, you also need to keep in mind that having a racecar as a daily (if you so choose) makes life much more difficult. Most every modification removes at least one aspect of comfort or street drivability from the car, so be sure to research any modifications you do for their pros and cons before slapping them on.

    Other than that, have fun, and be safe. Keep in mind, it's a hobby. It's meant to be fun, so don't stress yourself out about it.
     
  9. Mafix

    Mafix Owner Staff Member Administrator Donated!

    i got mine to oversteer, not snap oversteer, and never had understeer issues. took a lot to get there. an oversteering fwd is hard to drive!
     
  10. zk0729

    zk0729 Well-Known Member

    As we all know, your setup was far from "standard" or "basic" [emoji14]

    Sent from my SM-S820L using Tapatalk
     
  11. zk0729

    zk0729 Well-Known Member

    Rollin' Rollin' Rollin'....

    Okay, of anything I may post, this is more than likely going to get the most conflicting opinions on. Wheels.

    Now, stylistically, I couldn't care less what you go for. That is completely subjective. But here is what you should look for.

    Stock

    Stock wheels, typically speaking, are fairly heavy. Usually they're steel or basic alloy wheels, in the case of Celica's i honestly don't know, I haven't had stock wheels. If you have hubcaps, rest assured you're sitting on steelies. Now, stock wheels are designed to be tough enough to handle daily abuse, things like potholes, curbing, not paying attention while driving, the like. They're also designed to be as cheap as possible in order to lower the overall cost of the car. Personally (especially with our meager 14"), I don't see a reason to keep your stock wheels. But it's your choice.

    Cast wheels

    These are wheels that are made by pouring molten metal into a mold, typically made out of sand or the like. This is essentially the cheapest production type of any aftermarket wheel, and while usually "ok" stylistically and durability wise, but if you don't buy a quality brand (looking at you, XXR) you'll be pretty prone to breaking and especially on a track, this is catastrophic. As a whole, cast wheels are less durable due to the fact that during the casting process, the molecules of the metal settle horizontally across the surface, in line with the grains of sand or with the layers as it's poured. This means that an impact perpendicular to the wheel in that direction (which is pretty easy, that's how ANY impact hits the wheel) can cause it to crack and split along that line, which is no bueno. For any kind of track application, stock is a better option than cheap cast wheels.

    CNC (Computer Numerical Control) machined

    This is where things get a little complicated. Sometimes, brands will actually call CNC cut wheels "forged" or will say something to the effect of "made from forged material". The basic deal is that a forged block will be machined to fit a specific shape, which while usually stronger than basic cast wheels, are still structurally weak. This is because the molecules are aligned with the shape of the block, and not with the shape of the wheel. In addition, the cutting can weaken the structure of the wheel, and a lower end company will probably not address this. I would also say (especially given the cost) that you should avoid CNC wheels if you plan on taking your car to the track.

    Forged

    To keep it as simple as possible, this is going to be the best build process for wheels. Typically speaking, they're also able to use smaller spokes and more intricate designs without losing strength, so stylistically it's also a win. The process basically consists of taking some raw metal cut to a basic shape, and smashing the ever loving shit out of it with a big ass hammer (excuse the vulgarity). The reason this is a superior method of development is because this process makes the molecules align to the shape of the wheel, as opposed to being draped over it. This means that at any given angle, it's going to provide the best defense against snapping. While these can be rather expensive, unlike the other two you're less likely to see them degrade in strength over time (especially given the stance scene nowadays), so you shouldn't be scared of buying secondhand and having them refinished. If you plan to autocross, there's no real excuse not to use forged wheels.

    Wheel Sizing

    • Diameter - This is designated by the first number in a size (e. 17x8 +35). This tells you the distance from one spot on the rim of the wheel to the other.
    • Depth - This is the second number in the size (17x8 +35). This tells you how deep the barrel of the wheel is.
    • Offset - This is the third number in the size, denoted with either a plus or a minus (17x8 +35). This tells you how far or outset the mounting surface on the wheel is from the face. A positive number means that the mounting surface of the wheel is further in, making the wheel stick out, and a negative number is well, the opposite.

    Tire Sizing
    • Width - this is marked by the first number in the tire size (e. 185/70R14) and tells you the tread width. Tire sizing charts can be found online, should you wish to experiment.
    • Sidewall Height - This is the second number in the tire size (185/70R14) and is used to determine the sidewall height. It's actually based on an aspect ratio with the width, but we won't get into the formulas here. If you want to experiment with tire size, feel free to use an online calculator
    • Wheel Diameter - This is the third number in tire size (185/70R14), and tells you the diameter of the tire. This (obviously) must always match, while the other numbers can very depending on fitment and clearance you want.

    That's just kind of some basic info on wheels, to get you thinking about it. As with everything in the thread this will more than likely be elaborated on later.
     
  12. zk0729

    zk0729 Well-Known Member

    To Mod, or Not to Mod

    As much as I hate covering all of this information before even getting started on actually driving, but I'm trying to provide the most information as I can. Anywho, that being said, let's cover some of the basics on vehicle modification as it pertains to autox.

    What should I change?

    Now, if you have to ask around for what you should modify on your vehicle without some kind of "I want it to do ____, better", you're asking the wrong question. The only time you should make a modification is when you are fully aware of what it will do, and you are certain that you have a problem with it the way that it is. For example, if you haven't gotten passed due to a lack of acceleration, then do you really need to do it? Everything you do on your vehicle is going to give you one more thing that can potentially fail, or something that can change the way it drives in such a way that you may no longer enjoy it or be comfortable driving it. If it's not broken, don't fix it.

    If it is broken, improve it

    On the other hand, if a part has already failed and you wouldn't mind improving the part with something new, by all means give it a try! There are many things that are objectively better, like fuel pumps, hoses, speakers, brake/clutch lines, calipers, etc., so as soon as these things fail, it is perfectly logical and well advised to make a change. This is why research is key in motorsports, regardless of type, no one can tell you what you need to be a better driver.

    Know your enemy

    Whenever you plan to change something, you need to understand how it works. While with a daily driver, you may never have to worry about how your replacement part works, just that it fits, when it comes to racing you have to understand not only what may have failed, but why. That way, you won't be repeating the mistake a second time. If you're replacing the clutch, you should know exactly how the clutch works, and how the replacement will change the response and structure of it. If you're replacing your suspension, you should know exactly how your stock setup is designed, and exactly how the new one is as well, and how they differ. If it seems scary, don't worry. You don't have to learn everything at once, you can simply take it one thing at a time. Rome wasn't built in a day.

    Now, also keep in mind that every car has their Achilles heel, and you need to know exactly what it is. Throughout the site there are numerous accounts about necessary general improvements, so I'll try not to delve into that too far here (hint though, oil pump and starter relay). While you'll never be able to eliminate every single drawback (because everything you do has pros and cons), you can at least save yourself time and money by reinforcing your known weak points. Like I've said a hundred times before, and will a thousand times again, you need to research everything you can. While first hand experience is great, there's nothing wrong with using the information available to you.

    (to be expanded)
     

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