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This page outlines the parts that I have added to my IROC. I'll also cover the parts that I don't think work either from testing or cost. I've listed the mods in stages that I feel best maximizes the power and wallet of the owner.

Stage One

Cold Air Induction

I used a K&N cylinder filter and a 3in radiator hose with a 90 degree bend. Ducted the filter under the battery tray. I had to cut the corner off the tray so that the hose cleared alright. The cost was around $50,00. Picture 1 and Picture 2.

Dynomax Cat-Back Exhaust

The kit replaces the 1 7/8 over axle pipe with a 2 1/4 mandrel bent pipe. The muffler is a Super Turbo muffler that sounds great at the top end. The cost from Forward Motion was $90.00.

52mm Throttle Body

The 52mm is an upgrade over the stock 46mm. The only change is to cap off one of the vacuum sources. The 52mm TB is off a 87 Caravan with a 3.0. Others said that the 3.3 worked for them. My first TB was off a 3.3 but the throttle cable lever was totally wrong. I traded a MP turbo I computer for my throttle body.

Stage Two

Mopar Autocrossing Springs/Struts/Shocks

I decided to lower my car because I had blown a strut during SDAC-7. So I took this chance to do so. I used MP autocrossing springs and struts/shocks. The approx spring rates are 200 lb per in up front and the rear is 275 lb per in. Total cost for springs and shocks were $269.93 plus $30 for someone to assembly them and a $40 dollar alignment. Below I have a chart on each company that offers springs, their spring rates and part numbers.

Forward Motion Underdrive Pulley

I thought that this was the end of the road for performance 3.0 parts. The underdrive pulley reduces the rotating of the accessories. If you have a full stereo system then this may not before you. This is the last of "cheap" parts. The pulley is $130 from FM.

Stage Three

Konis

Ok I had finally broken down and bought Konis for my car. The cost was $439 plus $20 for shipping. I got the best deal by far from RD Enterprises. Konis allow you to adjust the strut and shocks for your needs. The front are easy to adjust. The negative part, to adjust the rears you have to unbolt the shock from the axle. Now if you are driving a heavy car like myself, then I would recommend using the Suspension Techniques kit for the stiffer front spring rate. Shadows can easily get away with MP springs. While at it I also replace the strut mount and bearing since they had over 119,000 miles on them. I also got my alignment set to stock caster and toe-in with camber at -1 degree for more bit in a turn.

Eibach Springs

After switching to Konis with the MP springs, I still had a lot of body roll and front end push. So I swapped in a set of Eibach shadow spring kit, which has a higher spring rate then the Daytona kit. The Konis with Eibach springs added to an very neutral handling car. The car handled fast transtionals easily. You will need spring compressors to mount these springs. Coming from the MP springs I didn't need spring compressors to mount springs. I figured MP springs are a 1in drop, so are the Eibachs. I won't need the tools, wrong. So rent the tools, you will need them. The cost of the springs 245 dollars.

Brakes

There isn't much for a brake upgrades for our cars. I went with carbon kevlar brake pads($180). You get increased braking power and protection from brake fad over a stock pad. The kevlar backing helps protect the caliper from heat soak. I also replaced all my rotors($120) with brand new ones. This way the new rotors help dissipate heat. I also replaced the stock nasty brake fluid with new synthetic DOT 4 (2 bottles@$8). This way the brake fluid will start to boil at 480F vs. DOT 3s 200F. I really noticed the difference in the pedal and stopping distance. Now there isn't that sinking feeling when traffic suddenly stops. Just watch out for the person behind you, I have surprised quite a few people on the commute to work.

Cheap Horsepower

Move Coil to front of air plenum

In theory, reducing the coil wire will reduce resistance. Less resistance means more spark. You can see where I'm going. Can you say FREE power. Be careful, over a long period my coil bracket broke from the stress of being held by one bolt.

180 degree thermostat

Another Hotrod special that still applies. For Daytona owners, this is a must for you. Cooler the motor, the better it will make power. The added benefit is that it is good for the motor to. Can you spare $3.00?

8mm spark plug wires

This is your choice. I have used three different brands. I started with MP wires and now have Accel spiralcore. Both wire kits are universal, which means you have to cut your own wires. The MP wires were a pain in the ass for this. The core in the MPs was very brittle. The Accel cores was very strong and easy to work with. The MP and Accel wires cost me $40 each. My third set I used MagnaCore 8.5mm Race wires. This wire kit was direct replacement and has red wires(matches the car's color). Only problem I have with these wires are then come off or loose quite easily. My first autocross run with these wires, I was running on 5 cylinders. One wire came of the spark plug on the sixth cylinder. Cost of the MagnaCore wires 100 bucks.

Stiffer Motor Mounts

This next item doesn't increase horsepower, but helps put it to the ground. I used a polyurethane construction adhesive to fill the front and passenger mounts. Filling the tranny mount doesn't work well. The little hump on top really doesn't have anything to do with damping the motor. You need to put come shims between the tranny mount and its bracket. Make sure you don't use wood, it will get trashed and fall out. The shock mount on the back has 2.2TI valve spring o help out. This requires two people and hopefully a lift! This will help decrease wheel hop for harder launches. I bought a 10oz. tube and chalking gun at home depot for $10. I have filled five mounts so far. The valve spring was a gift from my friend Phil.

Here is where is gets expensive

Clutches...

With in one year I have replaced two OEM type stock clutches because of the clutch discs failing. So don't use Bruteforce brand clutches in your car. The bruteforce clutches don't hold up to autocrossing, drag racing or extreme heat. With that said, I have decided to spend some cash for my new clutch. So now I have clutchnet's Carbon-Kevlar clutch disc, double diaphragm pressure plate and new flywheel. My reasoning is that like my brake pads, the carbon-kevlar is easier on metal surfaces(flywheel/brake rotors), better grip and better heat resistance.

Let me explain what a double diaphragm pressure plate is. Basically when you shift gears, a throw-out bearing is pushed against the pressure plate. Well the bearing actually pushes against the diaphragm of the plate to release the clutch. On stock, you have a single diaphragm for an easy, soft clutch pedal. A double diaphragm gives a much stiffer pedal, but much more pressure on the clutch disc over stock. Meaning more grip.

So am I happy with my new clutch? Kind of I don't like the stiffer clutch pedal. It has thrown my shift timing off, so I'm learning how to drive 5spd again. I haven't really tested it in racing conditions yet, so only time will tell. Would I recommend this clutch setup? Yes, but with one change. Get the carbon-kevlar disc, but go with the single diaphragm pressure plate. This way the car will still be comfortable in rush hour traffic. Is clutchnet a good company to deal with? Very much so, after they shipped me a defective pressure plate, they sent my a new one using UPS Sat. Next Day Air (over 100 bucks) at no cost to me.

The total cost of this project? Well since I did all the work myself, it only cost my $550 for the new clutch kit and flywheel. I was quoted $400 for labor from Firestone to do the install. Since replacing a clutch is a huge projected, you must consider how far you are willing go. It maybe easier to pay someone else. Luckily I have great friends to help me out!

If you got a heavier clutch, then order a spare clutch cable! I snapped mine in NH at an autocross. Luckily I was able to make the 3hr drive home fine. I also went back to a stock clutch for now.

Kosei K1s

If I hadn't spent some much money on my clutches, the wheels would been the most expensive item on the car. What can I say about these wheels, light and awesome! The amount of effort in rotating tires was well worth it. The wheels weigh 13lbs, come in 15x7 with a 38mm offset. With new 225/50R15 Yokohama AVS Intermediate tires, really helps makes this car handle. I reduced unsprung weight by 15lbs per wheel. The cost of each wheel is 140 bucks and each tire was 86 dollars.

Full 2.5 in exhaust

I went to a full 2.5 in exhaust with high flow exhaust and race magnum muffler. If you don't have future plans of forced induction then DON'T do this. I only gained 2hp and lost 3 ftlbs of torque over the mods list above. The total cost for the exhaust was $300.

Strut Tower Bar

I had a local shop make up a working strut tower bar. What I mean by working, it means it wasn't bar made for another car, then new holes drilled to make it work. My bar fits perfectly, uses same nuts on the car and clears my A/C line. No bullshit, wimpy bar for me. Is there a difference? Not really, I get a little bit more traction in turns but most people won't notice it. The bar cost me 185 bucks to have made. Picture 1 and Picture 2.

Superchips ICON

Well I finally worked out the bugs with the SuperChips ICON. Turns out that I had a vacuum leak and bad connections. It took two weeks to get my local dealer for finally find the part number for the hose leading from the map sensor to the plenum. Plus I found that my connections weren't' protected well. These the main reasons behind my code 14 and bad idle problems.

This is perhaps the most amount of money spent of very little horsepower. The ICON allows you to increase/decrease ignition timing. I only gained 4hp and 6ftlbs of torque for $500. This comes out to $125 for 1hp. Another problem with the ICON is that it could cause code 14, bad map sensor. If you get this make sure your connections are good and dry.

My view on the ICON is that it is a total waste of money. Yes I did gain hp and torque using it. Here is what I mean. You can buy the ICON in two flavors. The first is the cheapest. You spend $400 dollars for the unit but you can't make adjustments to the program. Another $100 dollars buys you the software and programming cable. Next you need a laptop to program the ICON. You can get a good used laptop for $1000. So now you could change the timing. I had to increase my timing up to 17 degrees advance to get any real gain. The stand alone ICON doesn't come with enough timing for any horsepower gains to justify the price. Which means that the $400 unit is a total waste of money. I have contacted Superchips. We exchange one email and now I'm being ignored. Another point, SuperChip had screwed my order up twice. So we aren't talking about a user friendly company.

Spring rate chart.

I made this chart for those interested in tuning their suspension. Since Chrysler cars share the same strut/shock mounts you can use a spring kit intend for a different model. On the Eibachs, I don't know why they have a higher spring rate for the shadow/spirit since the Daytona weighs a few hundred pounds more then a shadow. Where as Suspension Tech. shows the same part number for the G,P,A bodies. Go figure.

Company	Cost	Part #s	Front spring rate	Rear spring rate
Mopar	$135	P4452205,P4552206	200 lb per in	275 lb per in
Suspension Techniques	$169	P,G,A bodies	155	247
Eibach	$225	G, J body 2801.140	200	260
Eibach	$225	P,A body 2804.140	303	330