Setup
- Tires/Wheels
- Front: 17x7 (42mm offset) Raze R-74, 205/50/17 BF Goodrich gForce KDW 2
- Rear: 17x8 (48mm offset) Raze R-74, 255/40/17 BF Goodrich gForce KDW 2
- Alignment
- Front toe in: 1/4 inch
- Front camber: -1.6 deg
- Front caster: Mechanical maximum (I didn't have time to measure)
- Rear left camber: -1.8 deg (as much as I could get; the wheel is about to hit the knuckle. I need 18s)
- Rear right camber: -2.5 deg
- Rear toe in: 1/16 inch
- Shocks/Springs/Bushings
- Front springs: Stock with 1 coil removed
- Front shocks: Koni reds
- Front swaybar: Stock, with Rodney Dickman's solid endlinks
- Front bushings: Polyurethane everywhere except the swaybar mounts are stock
- Rear springs: 350 lb QA1
- Rear struts: Koni reds, adjusted somewhere in the middle, flipped top hats
- Rear swaybar: None
- Rear bushings: Poly on the trailing links, solid rod end lateral links
- Weight reduction/relocation:
- Front mounted Miata battery (23 lbs), mounted behind the front crossmember
- Corbeau A4 seats on original Fiero sliders
- Removed jack, wrench, spare, and spare tire tray
- Engine:
- Balanced and blueprinted 1993 3.4 DOHC V6, custom intake, 220whp on a Dynapack
- Transmission:
- Fiero Getrag case with later Getrag 282 internals (slighter shorter 5th gear, larger and stronger diff)
- Clutchnet kevlar clutch, Luk pressure plate
- Exhaust:
- Stock exhaust manifolds and crossover, 2.5" cat, custom 2.5" single inlet, dual outlet muffler
- Brakes:
- Slotted/drilled 12" Corvette rotors
- 88 Fiero calipers
- Porterfield R4-S pads
- Factory replacement brake hoses
- Steering:
- 2-turns lock-to-lock power steering rack from a C4 Corvette
* Fiero Getrag gearing is not ideal
* Easy to put power down
* The super fast ratio ZR1 steering rack is awesome
* Brakes could use more rear bias
Power/Gearing:
The gear ratios really break the car for autocross. I can go full throttle in second gear when going straight or mostly straight and not loose traction, nor hit the rev limiter, so it needs to be shorter. First gear is only usable for the launch, and the beginning of the course until it opens up. After shifting into 2nd, there aren't any spots where a downshift (and subsequent upshift back to 2nd) are practical, it scrubs off too much time. I think a Northstar in 2nd gear with a 7k RPM limit would be just right, or a turbocharged 3.4 DOHC with a fast spooling turbo and low boost.
With my motor, the Getrag gears with the shorter 2nd would probably be a lot better. I hated the 2nd to 3rd shift with those gears when I ran them though.
Fortunately (or unfortunately) I can't drive the car well enough to take too much advantage of the extra speed a shorter 2nd would give me, so it's not a limiting factor right now.
Handling:
The fast ratio steering is amazing. It's VERY easy to point the car where it needs to go, on even the tightest hairpins. I didn't have any problems with steering feedback. I can still feel the loss in self-aligning torque when approaching the lockup point during threshold braking.
Speaking of braking, it seems the fronts lock up pretty easily. I feel like the car should be able to stop faster. I think it needs more rear brake bias.
My car tends toward oversteer; if I turn in hard enough it spins out. I can countersteer and recover almost every time, but it scrubs off a LOT of speed when it happens. It's annoying trying to find the traction limit in a turn only to have the rear step out and then lose all your speed. This is the only serious handling problem I experienced.
Performance:
Hard to say. I don't really have enough driving ability to know how fast the car will run compared to others, and the oversteer problem made it hard to find the limit of the car. My buddy running an AP2 S2000 with lots of suspension mods but stock tire sizes and motor ran about a second faster than me. Both of us are novice autocrossers. Even if I could drive it well, it's hard to compare right now since I have four year old tires, and almost every other cars in my class (with the exception of my friend's S2000) is running RS3s or Z1s. That will change soon if I decide to continue developing this car.
Video
Unfortunately the videos didn't turn out too great. My GoPro's battery ran out before I could get more than a few seconds of useful video of rear suspension motion. I'll try again at the next event.
Photos
Click the images for bigger versions.
DPP_0355 by Borowski.G, on Flickr
DPP_0357 by Borowski.G, on Flickr
DPP_0441 by Borowski.G, on Flickr
I'm running -2.5 deg of camber on the rear right, but you can see it still goes way positive due to body roll. Look at how much the inside is lifting! Note that I am not running a rear swaybar. When I did in the past, it made things even worse.