I thought I would add a little more information now that I have a little time. Previous post was in an awefully boring Astronomy class and I only had 50 minutes.
I didn't mean to come across that Escorts were total crap...they aren't. They are a great coil over at the price point, especially if you get them used or discounted. They just aren't up to the task of modern coil overs. By not up to the task I mean they are not as advanced. In my experience with 600/180 and 545/212 over the counter setup is as follows - original feeling was superior, especially with the 400/450lb springs. I got a chance to track my car and started to see the problems. My setup was the Escorts, Hyperco 400/450lb springs, M030 bars with OEM bushings, OEM rear bushings, no torsion bars (I was sold the car with Racers Edge delrin torsion plate bushings, banana bushings, etc which was all a lie, and unfortunately these were things that the PPI couldn't see). With the M030 rear bar set at middle (neutral setting) the car had decent turn in with pronounced power-on understeer. This was before I knew much about shocks/springs so the first thing I did was put the M030 bar on the stiffest (furtherest from the end) setting. Car had worse turn in, nearly the same power-on understeer, and really little difference from the peanut gallery. Next step under the reccomendation of many vendors who I spoke with was that my springing was off. Between several vendors I was told rates from 500/400 to 300/600. Everyone has their own 'recipe' for the Escort setup. I kept my 400/450lb springs and ordered some 550lb springs to play with, since the entire setup uses 8" 2.25" springs. With my setup, 550/450 did nothing but make the car all but a push pig. My car was corner balanced at 50/50 prior to the springing change, so IMO this made a very front biased suspension. I went to 550lb springs in the rear and it made the car much more lively. Now I was on 400/550, M030 full stiff, still under the impression I had solid bushings. Car was now much more neutral....for about a week. Then I hit a very small bump and the top of the strut snapped off. I can't really say much about this, only pictures do justice.
![[Image: M2.jpg]](http://i36.photobucket.com/albums/e18/whakiewes/M2.jpg)
![[Image: IMG_0806.jpg]](http://i36.photobucket.com/albums/e18/whakiewes/IMG_0806.jpg)
This won't happen to everyone, infact its a rare case. But it has happened, and when you call Bilstein and tell them about it before you finish explaining they know what has happened...so it must happen more often then people talk about.
So I started to do a ton of research. I put a friends Koni setup with Paragon coilover kit for the mean time while I sorted out what I was going to do. This is when I started with small phone calls which later became hours and hours long phone calls, which eventually became hour long international phone calls (one of those intrinsic costs I never added into the cost of my suspension setup). Once you start to get the deeper and deeper you realize that no one gets into suspension tuning because its so complicated. Bobby Archer spent over a million dollars and five years of research before he mastered the Dodge Viper ACR package suspension (Koni 2812's, but valved and specified by Bobby Archer Racing). You think any of the main Porsche vendors have the funds to do this kind of R&D...not likely. Bobby Archer will openly tell you his worst mistake was spending all of his time and money on suspensions and not performance like most people do. This is why so many vendors push pre-made kits like Bilstein Escorts, PSS9's, Leda's, etc... all of the basic R&D is done. Power is measurable by numbers, a dynomometer to be exact. What is suspension measured with? Imaginary numbers that are created to catagorize cars; skidpad, slalom, etc... so many variables that these are only numbers used to catagorized. What does show is performance on a track, time removed per lap...then again this can have just as many variables. Thus no one invests time nor money in developing a kit that is tuned for our cars.
So as I talked/shopped around I started to get into what makes a $1000 suspension different from a $5000 suspension. Well the simplest answer to the question is the quality of the parts. Steel vs. stainless, alumimum vs steel, welded coil over sleeves or threaded bodies, etc... What makes the differences - well steel rusts, plain and simple. See early Leda's (possibly modern Leda's). Many manufactures get around this by 'coating' steel, or painting it. Still is going to rust eventually, although there is a damper put on the time frame (i.e. you may not see it in YOUR ownership). Aluminum is the lightest, doesn't rust, and is one of the easiest to work with, but at a cost. Typically aluminum doubles the cost of a shock. Next are the internal parts of a shock - valves, tubes, oil or nitrogen, adjustable or non, life span, etc... Your over the counter shock uses very durable parts with conservative valving to make the shock last for a ton of miles. Custom shocks use more exotic valving techniques, very high stress parts, and add in more things to break. The benefit is a better shock; the downside is a short life span. These are the basics that make a shock more expensive than others. Typically as more exotic parts are used, more adjustment is added.
Adjustment - man this is my favorite part. This is where I have to put my boots on to wade through the crapcreek. My favorite are the 36-way adjustable japanese coil overs. It takes me a while, and honestly I still don't think I have it figured out, but here is my best guess. Each shock is 4-position adjustable, which adjusts compression and rebound 50/50 (hopefully), so (4X2)4 = 32, but that still leaves 4 more adjustments...whatever I am already lost. So as I said in my previous post you have none, single, double, triple, and sometimes 4-way adjustable shocks. All adjustable shocks have atleast rebound, doubles add in compression, 3-ways split up compression, and 4-ways I am not completely sure, but I think it adds in the adjustability of nitrogen tuning. The cost of adjustable shocks depends highly on how it is adjustable - early Koni's (pre-M030) had to be adjusted by compressing the shock and turning it, then later ones were able to be adjusted on the fly. So lets take two shocks for instant that are similar in pictures and specs, but in reality are completely different; Koni 3012 and 2812. Both are double adjustable, aluminum, mono-tube (making them able to mount invertably) and made my Koni. One is $550 and the other is $1100...each. To the naked eye and the naked buyer there would be no difference; yet there is. The 3012 requires the shock to be completely removed so it can be at full extension to adjust compression. Rebound is adjustable on the fly. Also there is the fact that the adjusting mechanisms are not as precise so when you adjust compression two turns (whatever value that may be), your adjusting rebound as well. What if you didn't want to adjust your rebound though? See most shocks that claim independent double adjustability aren't...closer to 90% double adjustability. The only way to find this out is via shock dyno's which most don't have access to, so the marketing wins again. The 2812 offers the same aluminum mono-tube structure as the 3012, but adds in easily accessable on the fly double adjustability. Furthermore its adjustments are made on a specific user defined pattern (7 clicks) so precise tuning can be had. Also because of the rod adjusting mechanism (also used by Advanced Design and Ohlins), the shock can obtain nearly 99.9% independent compression and rebound adjustments. This is what makes the difference between a $500 and a $1000 shock. Unfortunately the Escorts have none of this!
So why pay for this tuning ability - well seconds off your lap times of course. In my previous post we spoke about the fact that road conditions are never the same, tracks are never the same speed (some short and tight, some long and straight, some fast and narrow, etc..), tires wear out (which has a DRASTIC effect on handling), etc... all these are variables that one setup can not adjust to...no matter how much you pay. Having on the fly adjustability gives you the option to adjust for temperatures, tracks, competition, confidence, etc... This is an invaluable tool to a racer, or even a weekend educator/learner. Being able to adjust to your driving style inspires confidence which will inturn lead to faster times (until you have a few off track excursions because of over-confidence).
But what if you don't have $4000 to drop on coil overs...well thats gravy too. You can have your cake and eat it too because in the ends its what you want and what you are going to use your suspension for. The Escorts make a great feeling setup for the street/occasional track setup. Any driver that can hit 7/10th of the cars performance will quickly realize the faults though - way too much rebound and compression - 525/160 would be much closer to usable valving. There are other options as well - Koni 8611 double adjustable front inserts with Paragon's coil over kit and Koni 3012's in the rear would be about $1900 and be leaps/bounds ahead of the escorts provided you did a little tuning. KW V3's at $2500 retail would be miles ahead, and I have heard rumors of being able to get a setup for a hair above $2000.
A few more tidbits about 968 suspension while we are on the subject - camber plates - in all honesty they are not needed. There is so much adjustment from the factory that they are all but useless in the most literal form. BUT it makes the adjustments so much easier and if you choose to track the car they add a significant amount of extra camber - up to 4 degree's. Does the fact that the RE plates are the only ones available that keep the stock height matter? IMO not really, as anyone getting camber plates will most likely be on coil overs and can adjust that out. The downside is by adjusting this out your are using some of your shock travel. Worth considering over .01 seconds on a lap, but I doubt there will be a difference.
What about the rear mounts - I heard they can fail - The parts in question are the thin sheet metal double shear upper mount and the single sheer lower mount. Facts~ The factory uses grade 8.8 14mmX80mm bolts to secure the stock rear shock in. This shock does not see much force so in factory form it will never fail. In fact this bolt is strong enough that it could handle any coil over considering its anchored in over an inch. The upper mount is only welded sheet metal with washer type reinforcements. The fact is though that this mount rarely sees movement or force as its only a pivot point. The double shear design makes it strong enough to handle about any force pushing upwards. The lower mount is the problem though if your running monoball (spherical bearing) mounts. First they are about 1/2 the width of the stock shock mount; second they are 1/2" ID and the stock bolt is 14mm, so your 1.3mm too large, and third 1/2" does not fit into a 14mm socket. So what fixes this delima - well RE was the first to the market with a double double bolt. They are readily available if you choose to shop around, but you may need to buy the RE parts to get the sizes right unless you just want to guess. Essentially what a double double bolt does is use a 14mm base bolt that is tapped on the inside of it. As a bolt this is good for no torque, in fact it isn't even graded. The inner tapping is for a 1/2" so now you have made up for the distance due to the narrower bearing. When these two bolts are bolted within each other the gradless 14mm bolt becomes at a minumum of a grade 8.8, typically more though. Makes a VERY strong bolt that also makes the strut fit. The funny part is that these bolts aren't used to make a 1/2" ID bearing fit into a 14mm socket, but are made for reinforcing 14mm bolts that need to be stronger than grade 8.8. So how much can these bolts take...well a lot. The mechanical engineering that I spoke with about these bolts told me that a high grade double double is nearly unbreakable. They are used in the most extreme of instances when the strongest bolts are needed. Karl told me he has tested them to 850lbs/in, so atleast that much. So are the parts worth $150? Of course not, they are worth about $65 it costs to order them from any bolt catalog...but your paying for the correct sizes, torque instructions, etc... so if I were to do it again I would purchase the same $150 RE kit before trying to fab something of my own.
A couple of good readings -
http://www.circletrack.com/techarticles/sh...ber_shock_dyno/
http://www.bimmerhaus.com/tech/shocktuningTN.html
Bedtime,
Wes
