Suspended!
11/27/2000Paul Romanych a.k.a. RedSS
Some truck enthusiasts like to have 2 feet of ground clearance under their pickup so they can traverse rough country without sustaining so much as a gravel chip on the paint. Some truck owners on the other side of the spectrum like the looks of a clean lowered truck and thus go to great lengths to make their hauler lay frame with the touch of an airbag toggle switch.
But true performance truck nuts, however, like to shoot down mountain roads that have more curvaceous corners than a room full of Playboy bunnies. It takes a great deal of money, engineering, time, and expertise borne of many years tuning frames and suspension to make a heavy truck like the 454SS even match a Corvette or Camaro in cornering performance, so let's get this ugly bit of information out of the way right now: if you want a true corner-carving monster, sell your truck and buy a supercar. But if trucks are just the epitome of coolness to you, you can keep it and make it much more agile than it came stock. You'll be lowering the truck in this process, so keep in mind what the truck will need to do-tow occasionally, haul dirt bikes or firewood, or just plain haul ass! If you honestly use the truck like a truck most of the time (i.e., transporting things), you might want to skip this article. The following is a member's questions, and a response from the author.
Q: I've been wanting to lower the truck a bit and get it to handle a little better (not feel like the nose heavy, torque-happy 4600lb monster that it is).
It's a truck; it'll still be nose-heavy unless you stick four 80-pound bags of gravel in the back and spend $25,000 on a custom all-aluminum big block.
Q: To lower the suspension and make it stiffer, I think I would want a 4/6-drop. In the back, I hear that the 6" flip kits ride better (feel softer or otherwise more comfortable-ed) than the 4" because the flip kit and inherent c-notch still gives you a lot of suspension travel, while hangers/springs will stiffen it up but have limited travel due to frame clearance.
Any time you lower the suspension with a stock non-stepped frame, you will lose travel. With a 6" flip kit, you notch the frame, reinforce it with the provided plates, and install a bump stop in the notch, and place the axle above the leaf springs using the stock springs, hangers, and shackles. Because you keep the stock springs when you install a flip kit or hangers/shackles, the ride is similar in quality to that of a stock setup. However, you do have more clearance to the frame with a modest 4" drop in the rear.
Guess at how much clearance there is to the stop from the axle housing with a 6" flip kit? 1.5 inches! DO NOT plan on putting anything with weight in the bed anymore. Even without the stop there is a mere 2.5" of travel and loading up the bed to maximum payload can actually bottom out the suspension without the addition of "helper airbags" or stiffer springs (more on that later). With a 4" drop in the rear, you have much more clearance due to the axle remaining under the springs.
This is something to think about if you live in rough country or have any concerns about speed bumps, or occasionally carry a moderately heavy load. With the stock springs there is little more bounce than with the stock suspension, as you are not increasing the spring rate (but you are installing shorter, stiffer shocks, so you will notice a tad more stiffness). If you install a heavy duty load spring on the stock leafs in the attempt to gain back the load capacity so as to retain the stock load rating (which isn't much to begin with), then of course the ride will be much stiffer and harsh in the back.
Q: In the front is where I have no idea. There are so many options, like 2" spring, 2" spindle, 2" arm? What is better and why?
Yes, there are a lot of options for the front. Commonly available to you are drop springs (1 to 3" drop available), drop spindles (1 to 3" drop available, 2" most common), and drop A-arms (1 to 3" available, 3" most popular). Let's take a look at each.
Used alone, drop springs will lower your ride adequately enough. Your ride tends to be stiffer as there is less spring travel to absorb impact (i.e., potholes). If your concern is performance in handling, this extra stiffness will be an advantage. But, the main advantage is that you will retain the stock ground clearance to the A-arms, which might be critical if you live in rough areas. Springs have come a long way since the early days of hacking a few coils off of the stockers, so there are some very good ones out there with "dual-spring-rates" (tighter coils on top and more spaced coils at the bottom) which smooth out the normal bumps but feel stiff in the twisty roads. These springs give you enhanced cornering performance and still have a good, soft ride quality for most daily driving.
Also used alone, drop spindles allow you to retain the stock springs for the stock-like soft ride quality if you prefer that to a stiffer setup (up to 3" drop). This is fine for a street cruiser where you want the low look but don't care much for cornering, as you will retain the stock springs. However, the A-arms begin to get dangerously low to the ground for most street use. On the stock wheels/tires, a 3" drop spindle will put the A-arm about 4" from the ground. You'll still be able to clear an occasional blown tire tread, road kill carcass, or other odd part in the road-marginally. If you want more drop than the spindles can provide though, you will need to add either springs or A-arms.
Lastly come A-arms. I personally have no experience with these. I'm not into radical drops and I find that installing springs in addition to spindles provide the most ease for the same results, both on the wallet and on the elbow grease. Add in the fact that they don't seem too popular with the sport truck crowd for some reason. You can get 5" total drop in the front with springs and spindles alone, which is usually more than sufficient (or streetable). A-arms typically offer lower heights without compromising as much ground clearance to the A-arms like spindles do. But, they are difficult to install; installing these requires you to remove all of the front suspension and A-arms and their associated bushings. If you want the lowest possible ride height with adjustability, you can go with airbags (which replace the springs and shocks up front) in combination with drop A-arms or spindles. This is the lowest you can go. As far as cornering performance, I'd question placing that much stress on the airbags that are commonly used for sport trucks. Airbags were designed to drop a vehicle at the touch of a button so as to provide a very low stance at a show and then raise the vehicle for the cruise home; no models I know of were designed for pulling high numbers on the skid pad. My recommendation is to stick with the standard shock/spring setup. "Load-helper" airbags (on pickups, installed in the rear only and in heavy vehicles like campers and RVs, sometimes in the front as well as rear) are a different animal, and will be discussed later. Personally I find that a combination of springs and spindles along with some good shocks will work just fine for most applications.
Q: Obviously, I'd want a 2" front drop w/ a 4" rear or a 4" front drop w/ a 6" in rear, right?
Possibly you don't. Trucks are built with an inherent "rake" to the rear end (the rear is higher than the front because the truck looks out of proportion with a normal load in the back yet the rear end is lower than the front…and remember, trucks were designed first and foremost to haul things). Dropping the rear 2" more than the front will level the truck out provided the wheel and tire combo you use is the same height in the front as in the rear. So, dropping the truck's suspension an even amount in the rear as the front (i.e., 4/4) will retain the 2" rake to the front. You can do whatever pleases your tastes: leave the 2" rake or not, rake it 1", level it, and so on. You can drop it 1/2, 2/3, 3/4, 2/4, 4/4, 3/5, 4/6, 5/7, or 5/8. Your options are limited only by your judgment.
Q: What would you do with a daily driven truck, given the average member's budget?
Here's my ideal cost-conscious hardware-only street setup for a truck that will not haul anything heavy (more than 350-400 lbs.) in the bed:
Front: 2" drop spindles with 2" drop springs, Belltech or better quality. Add stiffer shocks such as those by Belltech, DoetschTech or Edelbrock in 60/40 rate or something close. Add to this a beefy sway bar, with polyurethane bushings on it. Total package price should be in the $500-$700 range depending on what you get.
Rear: 6" drop flip kit with requisite notched frame to accommodate it. Install a thick beefy sway bar with polyurethane bushings. Use the stock hangers/shackles for the springs as well as the stock leaf springs. Lower, stiffer shocks, of the same type as you put on the front in a 50/50 rate round out the package. Total package price again would be about $300. Flip kits are inexpensive as most of the cost of installing them is found in time (or labor price to pay your chassis guy to do it).
For those that are worried about losing frame strength and payload capacity by hacking the frame, don't concern yourself with it. As for frame strength, I find that most of the time the kit-provided filler plates for the notch are sufficiently strong enough to take the rigors of daily driving and light towing. As for payload capacity, understand that if you're lowering your truck any amount, you're going to lose payload capacity and the amount of weight that you can have on the tongue of your trailer. I think it is worth the cost of payload in tradeoff for cornering performance to chop the frame and stick the differential above the springs. I don't put anything back there, and I doubt many people bought 454SS trucks with the intention of toting around heavy stuff. An interesting and added benefit of relocating the axle above the springs is that it reduces wheel hop as well.
Q: Can I lower it 6" in the rear and still retain some load capacity?
Yes, to a degree. If you need the load capacity of up to 600 lbs., I'd suggest utilizing a set of helper airbags in the rear that may be pumped up when you need them and deflated when you are not carrying anything. This can be a complete on-board unit with electric compressor and air bottle, or to trim serious weight from your truck and keep about $300-$500 more in your pocket, simply the air bags and air grottings so you can use your in-shop air compressor to inflate them before you tow/haul stuff, and deflate them with a small tool stuck in the grotting (simply put, like inflating and deflating a tire). This is optimal to an extra overload spring. Why? Well the overload spring will make the rear much stiffer all the time. Installing an overload spring will cost you ride quality because it makes the rear suspension much stiffer and in the process more prone to slip out from under you as the tires may actually be lifted off of the pavement when you hit the unexpected road hazard in a hard corner. You need suspension to absorb the transfer of weight when cornering and to absorb the shock of fast changes in road surface (i.e., potholes) so as to keep the vehicle glued to the road. With the light rear end and live axle of a pickup, the problem of fishtailing while rounding a corner at some illegal speed is even more pronounced.
Finally, with your new, tighter suspension, you need a set of good wheels in a larger size to realize the performance of your dropped sled. Tall, thick sidewalls are fine for romping around the local woodlots or job site in your mud-bogger truck or clearing the inches-deep potholes commonly found around the New York City area, but not for crisp road handling as the tall sidewalls flex too much. Many articles can be written on choosing wheel and tire size alone, but for the purpose of this article we'll keep this simple. 17" or 18" wheels, both practical and relatively easy to come by for less money than larger wheels (as the sport truck industry as a whole does not consider anything less than 20s as "cool" anymore), are my choice. Shielded with tires that yield the same total wheel/tire height as the stock SS setup, there is still enough sidewall on the wheels to absorb impact from road hazards such as hitting the average pothole at speed (which will bend the rim if you do not have enough rubber to take the shock and the rim contacts the pavement). A good recommendation is the GM Impala SS wheels, which look sleek and can be had for as little as $630 for a set of 4 from Jim Pace Performance Warehouse (paceparts.com), and which bolt directly on to the SS truck. Also, the wider the wheels you can stuff on, the better off your handling will be. In most cases, GM trucks with stock wheel wells can use 17" or taller wheels in up to 8" wide in the front and up to 9.5" wide in the rear. For your final decision, please contact a professional wheel/tire shop for compatibility before you buy-in most cases, wheels that have been grotted on a vehicle are non-returnable. Lastly, on a serious note, do take the time to drive your truck with the new suspension parts and wheels to get used to it before you start driving faster and making more risky cornering maneuvers. A mild tune to the suspension will put smiles on your face as long as your license does not get SUSPENDED! in the process.