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View Full Version : The modern drop - Informative article on car lowering


mrpayner
04-04-2003, 03:47 AM
[color=#000000:post_uid0]Hi People,

This is an informative article I found about lowering your car the right way. I did not write this article. Enjoy *[It's a long one!!!]

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In this article I am going to try to address all of the major and minor considerations that will come into play for lowering of your vehicle. What we are going to be discussing is what is entailed in this process, what it may cost, how it is performed, how it affects the demeanour of your vehicle, and the benefits and disadvantages to such a conversion. I want to start off by saying there is going to be a slant towards the smaller import owner (Accord, Civic, Eclipse, Celica), but the concepts and products mentioned do extend to larger American muscle cars (Mustang, Camaro) as well as a number of more recent trucks (Durango, Blazer).

There are many reasons people will drop their cars. The primary reason is for performance rather than looks, though that is a distinct side effect. The number of folks that will drop their vehicle for the purposes of looks is going to be relatively small simply considering the cost involved, esp. on larger vehicles like an SC400 or 540i. So, as such, the most drops you see are in fact performed on cars that have a slant towards performance anyway. Also, for the vast majority of the car owners out there, a drop is not even going to enter their mind, EVER. It is a specialized line of products intended for a growing niche market.

The purpose of a drop (a mild drop for this example) is simply to lower the centre of gravity on the given vehicle to enhance overall performance. This is achieved in several ways. Most factory vehicles are fit with springs that feature a linear rate. This means that the spring will compress at constant rate, i.e., the first 1" compresses as fast as the middle 1" and so on. This fine for everyday driving and will give a pudding smooth ride on the freeway, but it has drawbacks. A factory car, not including sports cars intended for aggressive driving, will tend to wallow on large radius turns and even lurch violently on panic manoeuvres, the high stance of an SUV dramatically exacerbates this. Also, springs of this type tend to isolate much more than an aftermarket spring, further muddying the driverís ability to truly interact with the road.

Progressive rate springs, which is the type you will see almost across the board in the aftermarket, feature a design that compresses faster in the first portion of the spring and then goes to a "harder" rate that will compress more slowly. So the benefits of a good aftermarket spring? Better ride through increased response to the road, lowered centre of gravity allowing for more spirited driving, progressive rate springs that contribute to the ability to drive harder, and lastly, a bold new look to your vehicle, something that says "I'm fast" even when standing still.

Springs are not everything though. The other major component of a good drop is aftermarket dampeners (shocks). One can very successfully put lowering springs on factory dampers, though it's far from ideal. The aftermarket dampers are intended for the reduced suspension travel that will result from the new lowered stance of the vehicle and many times are simply better than what is available stock or from your local parts store. One can see these improvements in the form of better, stronger internal components, improved design, functionality, and adjustability. The adjustability comes in several forms, whether rate adjustable and/or ride height adjustable. Dampers most commonly come in four forms; standard "sport" or "race" dampers, coil overs, coil over sleeves (same as coil overs essentially, but adaptable to non C/O specific dampers), and threaded-body dampers which aren't the same as C/O and offer a more subtle ride, though still very responsive.

A coil over is a damper that features a "sleeve", if you will, that is threaded like a screw and has a perch secured by to locknuts that can be moved up or down to meet the needs of the driver. The damper itself, though is not the C/O, C/O refers to the whole entity, damper, spring, perches, ALL of it. This is not a fast process, unless you have a pit crew, but it does allow for virtually unlimited adjustability. The downside is that with the, generally, smaller springs on a C/O, the spring rate is such that hey can offer what could be called a harsh ride by somebody not desiring the extreme level of performance they can offer, but the adjustability certainly makes them an attractive option. Thatís where threaded body shocks come in. They offer the same level of adjustability, but feature a softer (though still performance minded) ride and can be used with virtually any brand of aftermarket spring, from Eibach to Neuspeed.

Cost of the parts and install vary from vehicle to vehicle. Larger more aggressive cars (Mustang) will often cost more in the way of parts than say my Accord, but it still in the same ballpark. Dampers can run from $35 to over $250 (C/O, which often includes springs too). Springs can run from $200 a set (4) to almost $200 each! So the purpose you have in mind for your car or truck will ultimately determine what you are going to spend...well, that and your personal budget. Overall though, one should expect the average car to cost from $650 to about $900 for a good set-up. Of course these prices are also determined by where you decide to purchase from, there are VERY good deals to be had on the Internet, you just have to look.

There are other costs to consider though. Dropping a car will give you good results if all the suspension geometry is correct, which, after a drop it usually won't be. If you drop your car ONLY 1", chances are you will not need any additional equipment, more than that and you will have to start worrying about alignment and camber issues. What are these things? Well, alignment is a given and though not always, it can be adversely affected by a drop, this is simple enough to fix, just be sure the folks you take it to know about dropped vehicles, the local dealership may do more damage than good, there are issues involved they may not know about, esp. if they've never been around customized cars and the steps that have to be taken to maintain them. Camber is simple enough to explain. When the tops of the wheels are closer than the bottom, i.e. the wheels are "leaning" inwards from the top, this is negative camber. If they are leaning out, it is positive. Depending on the application (vehicle) 0 degrees (straight up and down) is a good standard to aspire to. For some track applications negative camber is desirable, for Joe Blow 0 degrees is probably best, but again this varies from one application to another, there are a lot of variables here I am not going to address in this article

A mild (1.75") to deep (+3") drop will result in negative camber (for the average Japanese tuner). This results in only part of the tires "contact patch" to actually CONTACT the road. This is bad. It can make your car track oddly, or even dangerously, it wears the tire unevenly and quickly and can make the car dart erratically on curves and wet pavement, again, this is bad. What is needed to correct this is called a camber kit; this will straighten up the wheels for proper tracking and contact. Camber kits are made by a few companies, though the ones you will want to stick with, IMO, are the brands that have proven they do the job and donít rub the wheels, tires, or the interior wheel well. Progrees and Ingalls both make reasonably priced kits that can installed by a pro in a matter of hours. My thought is this; if you know you are going to drop it around 2" or more install the kit with your springs and shocks and save yourself the money of a second install.

I would get into the issues of steering knuckles and tie rod extensions for relocation of proper pivot point, but the times when these parts are needed are rather few and far between and are generally relegated to those "slamming" their cars to the ground. There is nothing wrong with that, but the ground clearance issues make a strong argument for not driving in town, esp. if you have big wheels and low (or stupid low, like 35 or 30 profile) tires. Its an easy way to bend a $$$ rim! Well, that and bottoming out your suspension. Its not that you don't need these parts, but believe me, if you do, your installer will have already addressed this w/ you.

Ground clearance is another issue to consider when dropping your car. When you drop, 2" in my case, your pan, tranny, engine, etc, is just that much closer to the ground. Speedbumps become a labour of love, driveways become a challenge, and rough roads can stop you in your tracks. These are things to consider. By means of example, if I dropped my Accord even 1" more, there are parking lots in Austin I would not be able to enter because of how aggressive the speed bumps are. In most cases though, going at a bump, driveway or steep transition can be achieved with relative ease by attacking from an angle. So don't get freaked out at first like I did, just drive slowly and get used to it. I want to reiterate, the world will not become off-limits, you will just have to relearn how to drive in respect to how you approach the standard road hazards you've spent the rest of your driving life taking for granted. It is all worth it, trust me. You will take turns faster, you will dive into switchbacks more aggressively; you start to have fun behind the wheel like you did when you first started driving.

I know this has been long, but I hope you enjoyed it....if you even got to this point before allowing me to bore you into an HR. I take this stuff very seriously, and it is hard for me to be short in my thoughts. Below I have a few brands of springs and dampers to consider, they are not grouped as to cost or quality, but they are ALL of great quality, I would suggest nothing less. Happy driving and be safe!


Adam.[/color:post_uid0]