Impulse makes you do stupid things. Although I spent months contemplating the purchase of the right budget track car to help me get my NASA racing license, over the course of an hour, I got talked into buying a car old enough to drink. For a sum of $2500, I acquired a real gem, a 1985 Corolla GT-S.
Although I had considered the GT-S as a solid option for a street-legal track car, the reliability of cars like the EG Civic, Nissan S13, Mazda Miata and early RX-7 was far more appealing. But there was a caveat for each. The Miata couldn't carry a set of race tires internally and needed a roll bar, the S13's stock truck motor wouldn't last long under track conditions (and an SR was out of the question), and rotary engines were even more of a headache. It seemed I was destined for a Corolla or Civic. In a choice between price and platform, my shallow pockets and affinity for simple rear-drive cars won out.
I thought I knew what I was getting into. I had seen the car before and knew it was rough, but I thought it would be a relatively pain-free process to turn it into a street-legal weekend track beater. Contrary to my simpleton delusions, my GT-S was not a turnkey track car. In fact, it wasn't even a GT-S. The body was originally a carbureted SR5 with the 1.6-liter fuel injected twin-cam 4AGE motor from a first-gen MR2 thrown in. But it had all the right parts: the motor, ECU, harness, disc brakes, factory LSD and fuel system for the EFI setup. It even came with a Whiteline Panhard rod, Tokico sport dampers, and was already half lowered with cut springs in the front. What a deal.
Track Ready Restoration
I knew this car was bad news the moment the rear view mirror came off in my hand. I was prepared for new pads (maybe rotors), plugs, wires, and lots of lube. What I wasn't prepared for was a car that ran on only half its cylinders and an exhaust leak the size of a grapefruit. I don't know if that was more surprising or that fact that it made it all the way home on the night I picked it up.
So began a month's-worth of phone calls, parts searching and grease-covered weekends. I started with the usual fluid changes and maintenance part replacements. The two misfiring cylinders were on account of bad injectors - which were just replaced with spares scoured from various Corolla junkies - while plugs and ignition components came from the local Toyota dealer. It all sounds simple in retrospect, but troubleshooting and finding parts for even such a simple car takes a good day or two of time. Not to mention hunting down electrical bugs in 20-year-old wiring.
K&N Filters and Magnaflow provided the open element intake (PN 57-9000) and exhaust parts for a temporary solution to get past the California-mandated smog test. Instead of wasting megabucks on an exotic exhaust the stock cams couldn't take advantage of, I took Project Corolla down to MufflerMan in Placentia, California, to weld together a makeshift exhaust using Magnaflow's two-inch, pre-OBDII, direct-fit, high-flow cat (PN: 23886) and a six-inch cylindrical satin-stainless muffler (PN: 12640) with a straight-through design. The hack-job exhaust the Corolla came with made the direct-fit cat not so direct, so I had the flanges cut off and the entire assembly welded together, with a MufflerMan louvered resonator thrown in. Not knowing how low the car would sit once I put in some proper suspension bits, I decided to give myself some room to maneuver and route the rear exhaust piping above the live axle, just like stock. Magnaflow threw in a dual-wall polished tip (PN: 35125) to add some class to the setup. Had they seen the car, I very much doubt if they'd have bothered.
Everything replacement
With the car still in tatters and less than half a week left before its first track event, I took the deathtrap special to a local Corolla specialist, B-tune in Fullerton, California, hoping to make a last-minute rush to restore each suspension corner and get the car ready. It still needed replacement bearings, new bushings, wheelstuds and brakes (in addition to a thorough inspection of the undercarriage with the car on a lift), to make sure the car would get to the track, pass tech inspection, and survive the weekend-long beating without killing me in the process.
One of the primary advantages of the Corolla is its light weight. Even with weekend track use, the stock brakes will hold up to the moderate amounts of heat generated. But I wasn't going to trust the parts that came with the car. Both the front calipers and master cylinder were severely gummed up from years of commuting neglect, so those were completely replaced. The crusty rubber brake lines were swapped out at the same time, while the brakes' hydraulic system was cracked open. Because of the solid rear axle design, five braided stainless steel lines were provided with the Goodridge kit ordered from Tire Rack: one line for each corner and one connected to the hard lines on the chassis and the rear axle. With everything assembled, the remaining brake fluid was flushed out with Motul's DOT 4 RBF600, my choice for track abuse.
Hardware-wise, new rotors and Hawk Blue race pads purchased from Porterfield were installed. Ideally, I would have liked an economical two-piece slotted rotor with a more aggressive vane design to save unsprung weight and add cooling, but the small rotors and low demand probably means no manufacturer would consider such a product. Instead, I found a limited run of front and rear slotted rotors from Powerslot, machined from Raybestos blanks.
Hawk's line of Blue pads are designed almost exclusively for track use. Although many Corolla racers/drifters prefer a combination of Hawk Blues in front and the milder Hawk Blacks in the rear, I decided to use the same type at each end to maintain a near stock brake balance. The Blue compound provides friction at most operating temperatures seen in Southern California, so it works on the street, but the material itself is extremely abrasive. It eats rotors. Even with the Corolla's light weight and mild braking load, I've already ground a noticeable amount of material off the fronts. They also require proper bedding and heat cycling to reduce excess dust, noise, and rotor wear.
The stock wheels will inevitably be changed, maybe with spacers for a wider track, so the cross-threaded stock lug studs were replaced with longer pieces from Automotive Racing Products (ARP). Although listed as only a front application for the 1986-89 Toyota Celica GT-S (PN: 100-7718) on ARP's website, the stud shares the same 0.565-inch spline diameter and M12x1.5 thread as the Corolla GT-S and is almost an inch longer than the stock piece. This will give plenty of flexibility for spacers and whatever offset wheels chosen down the line. I also chased out the stock mag-style lug nuts with a tap to clean up the threads, and the ends were knocked out to let the stud poke through.
The only other task (for now) was replacing the stock bushings - easier said than done. Although the factory rubber bushings were in reasonable condition with no visible gouges or cracks, I still decided to replace them with a full polyurethane kit from Prothane. You can order it in pieces or as a Total Kit (PN 18-2010), which I got from SoCal Spec, a local wholesaler of most aftermarket off-the-shelf, go-fast parts for anything from a Corolla to a Mitsusbishi Evolution. Prothane's Total Kit comes with bushing blister packs for the Panhard rod, four rear lateral links, anti-roll bars and drop links in the rear, plus inner control arm, tie-rod, anti-roll bars and drop links for the front.
The kit also comes with different bushings for larger-diameter rear anti-roll bars. Most of these bushings will need to be pressed or burned out, depending on which tools are available. The guys at B-tune had a press, which made things easier. Since I didn't care about the stock bushings, mashing them out with a press was the fastest way.
Polyurethane bushings offer an economical suspension solution if you don't mind the stick-to-everything silicon bushing grease that has to be used. The drawback, in the case of Project Corolla, isn't the noise (there's virtually no interior or sound insulation to speak of) or ride quality.
It's that polyurethane bushings just don't have the rotational degree of freedom rubber bushings have. They must rely on bushing grease and the metal insert sleeve to allow rotation along the sleeve's axis, all of which is held tightly together with the suspension bolt.
This isn't such a big deal on newer multi-link designs, because the unsprung weight is minuscule compared to the weight of a complete cast steel rear axle and all its guts. In the Corolla, because the live axle weighs so much and carries so much momentum when the suspension travels, any added resistance or friction in the four lateral link bushings causes the axle to move lethargically, which means the rear wheels will spend less time glued to the pavement.
I'll address this later with lighter aftermarket lateral links, using Heim joints to both minimize friction and help reduce unsprung weight in the rear. I also prefer the consistency of all-metal ball joints in aftermarket tie rods compared to squishy bushings, because they prevent castor change as the front suspension gets loaded.
Track-style Russian Roulette
The same impulse that led to the purchase of Project Corolla led me to my hasty first shakedown session with NASA at Willow Springs Raceway, the fastest track in the West. The prudent would have spent the weekend driving the car around town to shake out the bugs, but instead I packed up the car and headed out on the 100-mile trek to the track well before dawn.
Just 10 miles from home, the Corolla broke down. Scratch day one on account of electrical problems and 20-year-old wiring. Day two of the track weekend started with the same determination, and by 9am the car was tech inspected and on the grid, ready for its rumbling debut.
I'll point out now that Project Corolla was never meant to be fast. Even a properly working stock GT-S would be no more than a moving speed bump on the track next to the Evos and rich-boy Vipers. But on a circuit featuring 100mph-plus sweepers and a front straight where stock Evos will peg 130mph, Project Corolla was completely out of its element. Outside of the satisfaction of making up a little time through the corners, I spent most of the time with one hand on the wheel and the other waving others by. In fact, the only car the Corolla would pass on the straights was an old MGB with both seats occupied. At least I made it through the 110-degree F day without any major issues.
Next time, I'll dump the cut springs and long shocks for some Ground Control coilovers, and get some performance numbers once the car is worth testing.