![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2010\/11\/Rainman-789245.jpg\" "\\"Rainman-789245\\"")
<\/a><\/td>\n<\/tr>\n<\/a><\/td>\n<\/tr>\n<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nYou just don’t tend to see the really fast guys driving old Camaros at SCCA events, and you almost never see the really fast guys at non-SCCA events. \u00a0They’re often running more modern and closer to stock Miatas or Corvettes, or whatever the hot car is that year. \u00a0The best drivers tend to flock to the platforms that are believed to be competitive, because they want to win! \u00a0It’s super rare to see somebody really good (and please, don’t for a second take that to mean I think I am) driving an oddball platform. \u00a0What this means is the general Good Driver rule still applies to Camaros- a “really good” autocrosser could hop in the driver’s seat of a “beginner\/intermediate” Camaro autocrosser, and usually beat them by a few seconds on 50-60 second course. \u00a0In some ways the non-competitiveness of Camaros, and many other interesting cars, is a self-fulfulling prophecy,\u00a0 as those who own them are likely to get discouraged by their early results and lack of any evidence they’ll ever be competitive, leading them to to not stick with the sport long enough to get any good at it. \u00a0Who knows, perhaps with some success maybe I can change that – I sure see more Nissan 240sx’s out there today than I saw before 2006.<\/p>\n
So there’s the driving element – if the person driving that Camaro wouldn’t be competitive in the Miata or Corvette or whatever, there shouldn’t be any expectation they’ll be fast in the Camaro. \u00a0Subtract a few seconds for a really great driver, and maybe the car looks a bit less bad?<\/p>\n
The other aspect of this relates to tuning and preparing the car to go fast in autocross, and skill in this area almost exactly parallels driving, though most people seem a little more willing to admit their shortcomings in this space.<\/p>\n
There is an unbelievable quantity of parts out there for these cars, as they’ve been undergoing speed tweaks for over 44 years now. \u00a0While as best I can tell the majority of effort into these cars for decades was around drag racing, the idea of making them go fast around corners has become very hot in recent years and the parts variety reflects this. \u00a0The “handling” renaissance begat a staggering quantity of suspension parts but not a lot of good guidance on what to do with them. \u00a0Individuality, limitless modification options with no rules boundaries, and differing levels of willingness to sacrifice street manners on the altar of speed, have prevented the crystallization of a “spec” setup for the Camaro. \u00a0A good example of a spec setup, is that for the super-popular Street-Touring 1989 Civic Si, published by Chris Shenefield about 8 years ago:<\/p>\n
http:\/\/www.redshiftmotorsports.com\/RedShift%20Tech%20Page.htm<\/a><\/p>\n With no spec setup to start from and no prior experience assembling a proper-handling autocross car, it’s no mystery so many of these cars end up not working very well, driving aside. \u00a0The Camaro as a platform is a deep dark hole to climb out of, too difficult to expect anyone to succeed with as their first autocross tuning project. \u00a0You can put your faith in what your suspension vendors tell you, but their answers are going to be targeted to the middle of their demographic, who may care more (or less) about a comfortable cruising ride, than you do.<\/p>\n There are some people floating around out there in the old-Camaro world who kinda know what they’re doing around the cones, I think, but since there isn’t really any sort of rules in the old-car specific events, it’s impossible to tell who’s doing a lot with a little (bit of modification), or who’s doing less, with a whole lot more. \u00a0Structure and rules are frowned upon in those circles, which is a shame because it makes results impossible to use in drawing conclusions.<\/p>\n I guess as a message to all my fellow old Camaro owners out there – if you really want to be fast in your Camaro at the autocross (and largely also, the track) – the best thing you could probably do, is park the Camaro for a while. \u00a0Get a Miata, or an S2000, or a Corvette, and go run a ton of events (SCCA preferably). \u00a0Figure out who the fast guys are in your region and track your times against theirs. \u00a0Even better if you get a similar car. \u00a0By getting a car that’s great out of the box, you can forget about setup and focus on driving. \u00a0This will teach you the importance of driving, while at the same time familiarizing you with the characteristics of a proper-handling car. \u00a0When you’re ready, then go back to the Camaro – I suspect the experience gained in a “good” car will better illustrate how far you have to go with your Camaro. \u00a0It should also help you better understand the importance of different modifications, and get you to spend the next few bucks on tires or shocks, instead of a supercharger.<\/p>\n How am I going to avoid this common problem? \u00a0By drawing on my experience as a driver and a tuner from many other cars, to dig this thing out of the deep dark hole it starts out in. \u00a0I don’t have any success stories to look to, but that’s part of the fun\/challenge.<\/p>\n BIG THING THAT MAKES EVERY AUTOCROSS CAMARO YOU SEE SLOW #2:<\/p>\n The stock front suspension really is<\/em> as bad as you’ve heard. \u00a0There’s a lot of things wrong; below I’ll attempt to explain just one facet of the wrong-ness \ud83d\ude42<\/p>\n Most of the old Camaros you see at the autocross look awful – they are too soft, and the front suspension looks like it’s doing the opposite of what it should.<\/p>\n Not trying to pick on this car or driver here – this photo pulled from http:\/\/www.milesspeed.com\/<\/a> – a neat site I stumbled across in researching these cars. \u00a0Car is owned\/driven by cool chick Liz Miles, and this was taken very early on in the car’s development. \u00a0Using it just to illustrate some of what’s wrong with the car’s front end; odds are if you’ve seen an old Camaro on an autocross course, it looked a lot like this.<\/p>\n Here’s another one from a 1967 magazine article on the original Z28:<\/p>\n That thing has no grip on the crap OE tires, but it still manages to showcase how utterly whacked its front suspension is.<\/p>\n Front grip is tremendously important in autocross. \u00a0At the track if you’ve got way more power than everyone else, you can maybe get away with a pushy (understeering) car, heck, it’s more stable. \u00a0But not in autocross. \u00a0You need to generate big yaw\/rotation, and you need to be able to change direction quickly. \u00a0The front tires do all this work and it’s the front suspension’s job to keep the tires as happy as it can.<\/p>\n Pretty much nobody with one of these old cars is giving them enough front tire. \u00a0I’ve seen cars with $10k+ in aftermarket grafted-on C6 subframes, uber expensive shocks, and mega-$ forged wheels … wrapped in 245 width tires! \u00a0With 335s out back! \u00a0That sort of stagger might work on a 911, with over 60% of its weight on the rear axle, but it’s a recipe for terminal understeer (and a frustrating\/boring driving experience) in a 55% front-weight Camaro. \u00a0If you want one of these things to turn, you need to give it all the front wheel\/tire you can, and nothing made today with a DOT stamp is “too much”. \u00a0My Viper had about the same front weight as most of these Camaros, and it had 335s up front! \u00a0At that size things were just starting to work right. \ud83d\ude42 \u00a0Obviously packaging is a problem but with all the effort put into everything else, I don’t see why more of those guys aren’t running at least 285s up front.<\/p>\n So to the subject of analysis here – the motion ratio – <\/strong>and boy is it <\/strong>TERRIBLE! \u00a0To many that may not mean anything, so let me attempt to explain. \u00a0Below is a photo of a stock ’67 Camaro lower control arm. \u00a0At the far left, the rod illustrates the axis upon which the arm pivots. \u00a0At a bit past 8.5 inches down the tape measure, are the two bolts that hold the shock. \u00a0When installed, the spring sits concentrically around the shock. \u00a0At the far end, just under 16 inches, is the lower ball joint’s pivot point. \u00a0Though you can’t see it here, there’s a hole for the stock swaybar attachment at about 13.5 inches.<\/p>\n So what’s the motion ratio, and why do I care? \u00a0Well, the motion ratio, is the ratio between how far the wheel moves, compared to how far the shock absorber (or spring) moves. \u00a0The further out on the arm the spring\/shock attach, the higher (and better) the motion ratio. \u00a0To calculate the motion ratio, you take the distance from the inner pivot to the spring\/shock attachment, and divide it by the distance from inner pivot to lower ball joint pivot. \u00a0If we round the pictured measurements a bit, we get:<\/p>\n Motion Ratio = 9\/16 = .5625<\/p>\n This means, for every inch of wheel movement, we only are going to see .5625″ of spring\/shock movement. \u00a0 Okay, so why’s that bad?<\/p>\n It’s bad because we depend on our shocks to damp the motion of both our unsprung (wheel\/tire, 1\/2 our suspension) and sprung (the rest of the car) weight. \u00a0 The better a job the shock can do, the more consistently loaded our tires will be, the more grip we’ll have, the faster the car will go around the corner, the lower our laptimes. \u00a0This motion ratio is about 30% lower than the motion ratio of a good modern car.<\/p>\n Below is a pic of a Viper’s front corner – look at how the spring and shock attach waaaaay out on the arm, right next to the lower ball joint: The Viper enjoys a much much better motion ratio than the Camaro.<\/p>\n Shocks depend on velocity to do their job – if they are not moving, they are not displacing fluid, which means they aren’t doing anything. \u00a0The more shock travel we can get per unit of wheel travel, the better we can control every microscopic bit of that wheel travel. \u00a0 This also allows us to control things with lower shock forces, which makes it easier to find reasonably priced units.<\/p>\n In an autocross car with a good motion ratio, we’re generally looking for what the shock does at about 3 inches\/second on a force vs. velocity graph (explained somewhat here:\u00a0http:\/\/farnorthracing.com\/autocross_secrets20.html<\/a> ). \u00a0Most of the movements the suspension sees on an autocross course are in this speed range, so that’s where we care about what our shocks are doing. \u00a0Shock velocities above that speed (bumps) are important too but somewhat less so, they’ll be a subject for a later day.<\/p>\n So getting back to the Camaro – with a motion ration of .5625, we’re only getting about 2\/3 the shock travel or velocity, of a “good” suspension car. \u00a0So whereas they get to build their shocks to work at 3 in\/sec, ours have to be doing the same quality of control, with 2 in\/sec. \u00a0The problem is, accurate control and large forces at these low shaft speeds, are very hard to come by – any of the common shocks available over-the-counter just aren’t going to get it done, at least not very well. \u00a0But wait, it gets worse!<\/p>\n Spring rate by itself is a not very good indicator of how stiff a car is – what’s more useful is the “wheel rate”, or maybe the “natural frequency” of a suspension. \u00a0Here’s an online calculator if you’re interested to find out yours: http:\/\/www.racingaspirations.com\/?p=292 <\/a><\/p>\n Those that have ever ridden in an unladen 1-ton pickup truck, and been bounced all around, have experienced a high wheel rate, and a high natural frequency. \u00a0The high natural frequency is caused by a very high wheel rate, combined with not much weight on the spring (an empty truck bed). \u00a0If you’ve ever then loaded up that bed with a few thousand pounds and noticed the truck suddenly rode much more comfortably, it’s not because the wheel rate went down (in some leaf systems, it might actually have gone up) – it’s because the natural frequency has gone way way down due to the weight\/load in the bed.<\/p>\n We arrive at wheel rate by taking the motion ratio, and multiplying it by itself – “squaring it”, in math terms, then multiplying it by our regular spring rate. \u00a0In the Camaro’s case, .5625*.5625=.316. \u00a0That means that for every 1 pound of spring rate, we are going to have .316 pounds of wheel rate.<\/p>\n Wheel rate and natural frequency are concepts you can use to compare the stiffness of any two cars, regardless of suspension type. \u00a0You’ll often see sliding scales where 1hz is “comfy street car”, 1.5hz, “sporty car”, 2.0hz “race car”, 3.0+hz “race car with aero downforce” – something like that. \u00a0Those are really just broad generalizations and by no means limits on what you can do with your car.<\/p>\n<\/p>\n<\/p>\n<\/a><\/p>\n<\/a><\/p>\n