Advanced Suspension Mods

[Advancedynamix]

I don't have pictures of this yet, but if you shorten the lower part of your shocks you'll need to also grind some material away from the beam where it will hit the lower part of the shock. if you install the shocks first without springs, and then use a jack to stroke the suspension through it's full arc, you'll see where it needs to me trimmed, it shouldn't weaken the beam at all since this material isn't supporting anything. I have put this setup through close to a hundred hours of pure abuse and haven't had trouble with it at all.
I'll post videos of some fast laps (6 seconds faster than the video where i catch the Ferrari) when I can get my computer to cooperate.

With Shortened shocks, I don't need to rely on a rear sway bar because I am eliminating the static sag in the suspension. I only have an inch and a half of droop, so the car can't roll much before it tries to lift and with the raised roll center (accomplished by lower the static ride height of the car) it requires much more force to lift the wheel than before. This car pulls over 1.5gs in corners. I don't have the data, but I do have footage of it turning under prepped Miatas on r compound rubber at a much higher rate of speed. It works and it's pretty comfortable on the street. I can nail speed bumps at whatever speed I want and it soaks them up well.

[Advancedynamix]

Here is one of the rear spring hats that I made. The kit came with some, but I wanted lower profile ones that mated up with the stock shock bushings better. You could use an assortment of thick washers from the hardware store to do the same thing.

Here are the finished shocks
and installed

And notice the clearance! They offer 4 real inches of suspension adjustment without sacrificing tire room!

[Advancedynamix]

Here I machined the bushing that holds the spring perch on the KYB shock. You dont have to do this, I did because I have a lathe, but you can use hand tools or carefully use a grinder to do the same thing. This is what will hold the sleeve and spring up.

[Advancedynamix]

here I'm machining and threading the lower part of the shock body.



it threads together then I welded it.

[Advancedynamix]

Here is a picture of all the components disassembled and assembled. These are made of KYB shocks for the Festiva/Aspire.

Here is a picture of the stock Festiva shock and spring next to the modified KYB. This is before I cut the 1.5" out of the shaft. I don't have pictures yet of the latest shock mod.

Here is the shock with the parts all cut off. The top dust cap is removable with a punch and small hammer. You may need to file down the shock body a little bit around the welded seam at the top to be able to slide the small body sleeve over the shock.

[Advancedynamix]

Okay, after promising this thread for some time now, I'm actually posting something. Lol. I'm just going to explain the basics tonight and put up a couple pictures, but there will be more as time goes on.

My Goal: To have a Festiva that is both street worthy and track worthy. By street worthy I mean it can be daily driven here in Arizona where we don't get much rain, the roads are well maintained and I don't have potholes to deal with. Track worthy means that the car should be competitive in Time Trials and be fun to drive in street specific run groups. This car isn't being set up for a race class because I played that game for years, with many many different cars that race in many different sanctioned classes and it now bores me to death to have to follow the rules. This car has no limits or rules other than the ones I set for myself.

Simple theory: I prefer to work within the factory dimensions and with as much OEM equipment as possible before relying on one off, exotic, race parts. There are a couple good reasons for this. It lowers the cost of replacing parts and the factory has a much bigger budget than I do, and they weren't screwing around when they designed these parts to begin with. The chassis and suspension parts were designed to work together for hundreds of thousands of miles, that's much longer than most race parts last. So I like to push the limits of the factory components until they break and make improvements based on the failures. Most of the time, minor adjustments can be made to OEM parts to give the car a handling advantage. With this said, a great handling Festiva is not that far away! These cars don't require much to out handle just about anything on the road.

FWD Theory: Many people seem to think that FWD is a handicap on a racetrack. They are sadly mistaken. More often than not, the advantages of a front drive chassis are lost when the cars are set up like rear drive or AWD chassis. FWD is the ultimate low cost chassis! The manufacturers have known this for half a century or more, that is why almost all budget cars are FWD. The concept is simple. Since the Front wheels are doing all the work, that is the only part of the chassis that gets the bulk of the strength, and suspension technology. Since the drive axle and the crankshaft are inline (sans Subie, Audi, some VW and older SAABs) the power delivery is up to 40 percent more efficient, requiring less parts and less driveline weight. This makes a more reliable car, and for my purpose, a car that responds much better to modification.
The FWD chassis main arch enemy is weight, especially weight rearward of the front axle. This is why the Festiva is such a gem. There is very little weight rearward of the front axle in comparison to many other FWD cars. The more weight you have to literally drag around the harder it will be to put down power without spinning, and the more grip you'll need to change directions or slow the car. Also, rearward weight will act as a pendulum when the car is asked to turn rapidly, which can cause oversteer. The goal is to be able to turn at a higher speed and use all the available grip without oversteer. Rather than forcing the car to rotate, like what is needed in a tight autocross coarse or in rally racing, on a road coarse we are looking for precise "turn in" and a chassis that is balanced and responds well to throttle as well as brake input. The best way to improve a FWD cars "turn in" is to remove weight from the back of the car, and add weight in front of the front axle. Weight in front of the front axle is transmitted to the front tires, the ones that will turn the car. Along with proper weighting of the chassis, you also need proper tires, brakes spring rates and dampening as well as a higher roll center and lower center of gravity (lowering the car). Things like 50/50 weight distribution work on some cars that use their back tires for more than holding up the fuel tank, but our cars are only using the rear wheels to hold up the weight we have behind the front axle. The more weight you have back there, the more work the back tires are doing and the less HP you can put to the ground without spinning.

Applying The Theory: Now the fun part, taking the simplicity of the lightweight and rigid Festiva and making it shine. The suspension on a Festiva is sort of a grab bag of great ideas that were present on some of the most famous cars in the sport. When I first looked under a festiva I was amazed to see a simple integrated sway bar drag link strut suspension in the front, not unlike some of the fine German Vintage race cars that I have set up in the past. That's right, your festiva shares a front suspension design with an original Porsche 911, and a BMW 2002, and several audis and even the VW super Beetle (hated in this country, but sort of a racing icon in Germany). In fact, if I were to list all of the cars that have serious motorsport pedigree with this style of suspension in the front I would be typing for days. In the rear of the Festiva I found the most compact and efficient trailing beam that I've ever seen. Having tuned many of VW's early front drive cars I am very familiar with the benefits of this amazing and simple design. It's lightweight and integrates a sway bar, it's a trailing arm which is far more efficient at bump absorption than wishbone or A-arm. It's the perfect rear suspension for a lightweight car. So here we have it, the festiva is already just about perfect, all it needs is a little tuning to use these excellent components to their maximum potential. The challenge is to lower the cars center of gravity while staying within the working range of the factory suspension. For this, I had to make some modifications to the shocks. Since the factory units were not intended to be in their working range at the ride height I want to run, I had to use something different.

Front Shocks: On the front I used Raceland Coilovers intended for a MK3 VW. I modified them to fit the Festiva/Aspire/Capri/323 ect ect, steering knuckles and I made busings so that they would fit snugly in kia rio strut tops. Since the Raceland struts can be disassembled, they are easy to weld without risking damage to the strut assembly. This also makes it easy to change out the strut insert for a double adjustable Koni race strut or a monotube bilstein. I have actually had great luck though with the strut insert that came in the Raceland setup.
Since the Racelands were intended for the heavy Mk3 VW, they come with springs that are much too heavy for even a B6t G series swapped festiva. I opted to replace the 300lb springs they came with with 200lb springs. I'm still running the stock festiva sway bar, and control arms, but I've installed some MOOG blue sway bar end bushings. I'll post pictures of the front shocks later, but you can also check them out in my gallery on my profile page.

Rear Shocks: In the rear, I have modified KYB shocks that are sold for the Aspire (same thing as a KYB for a Festiva). I cut off the factory spring perches and installed some threaded adjustable sleeves intended for a "small body" racing shock. These sleeves use 1 7/8" springs, rather than the more common 2 1/2" springs. This gives me more adjustment without sacrificing tire clearance. I also shortened the bottom of the shocks by almost 2" and the shafts are shortened 1.5". Don't attempt to shorten your shocks unless you have a lot of fab experience or know someone trustworthy who does. As far as the 1 7/8" sleeves, it's a moderate difficulty job and anyone who has put on the "ebay honda" springs can do these. I'll post some pictures in a following post. I've found that for street tires, 120# springs seem to work good and for sticky R compound tires I'm using 175# springs in the rear. My car is gutted and I have a stock Festiva rear beam.

Alignment Settings: The car seems to like 1/16" (overall, not per side) toe out in the front, neutral toe in the rear to 1/16" toe in. With the toyo proxes R888 tires it seems to work best with -2.2 degrees camber in the front and -1 degree in the back. This is just what worked for me, I'm not saying it's the best setup, but it is streetable and it is easy to drive at the limit. Rotate the tires every session if you drive the car hard and my fastest lap times were actually with the tires mounted backwards! lol.

Overview: I have a lot of experience setting up suspension on may different cars, but I'm not writing the Bible here. If anyone has a setup that could work better, or any hints to help then post it. I kept setups a secret on cars that I built for a long time, but now I just want to go fast and have a good time without a million dollar budget so that takes the help of friends and other enthusiasts. Thanks in advance for your input and interest. Sorry for the stuff I have left out. I just want to get this threat started. I'll update it as much as I can.