In Part One of Project Celica, we discussed the plans for our Toyota-backed project car. We discovered that, even in factory trim, the 2ZZ-GE was easily capable of laying down 160-plus hp to the front wheels on a Dynojet chassis dyno.
This is pretty impressive, considering the Celica is factory rated at 180 hp at the flywheel. The 2000 Acura GS-R, which we have also tested, only registered 140 hp to the front wheels from its 170-hp flywheel rating. Even bone stock, the GT-S was considerably faster than a stock GS-R. Thus, we knew from the start that trying to squeeze more power from an already extremely efficient engine was going to be tough.
The first area of improvement we looked at was the factory exhaust system. Most factory systems incorporate the common individual sections of the header, catalytic, mid pipe and muffler. The GT-S, on the other hand, utilizes a combined catalytic and mid-pipe section, which makes improving this section impossible without drastically affecting the Toyota's emissions.
On top of that, the catalytic and mid-pipe section is also part of the header. The header section that connects to the mid-pipe is only the first section of the header. The mid-pipe itself incorporates a partition plate, which acts as the second section of the header.
Although we tested 10 different exhaust systems on the Celica in the "Exhaust Shootout" (September, 2002 issue), we decided to retain the Veilside Tear Drop titanium system as part of our project build-up.
Compared to the rest of the systems we tested, the Veilside unit was considerably lighter, due to its titanium construction. Power improvements were also substantial, considering it was only the canister section of the exhaust.
We were able to increase the peak power from 161.0 hp to 165.3 hp--an improvement of 4.3 hp. The exhaust tone from the system is nearly identical to a CART car as it blasts down a high-speed straightaway. If you're looking for a quiet exhaust, the Veilside is not for you. At 3000 rpm, the sound can be disturbing if you are trying to enjoy the tunes of your radio.
The next area we examined was the induction system. Toyota decided to make things difficult to improve, similar to the exhaust system, by incorporating a dual stage airbox. At lower engine speeds, a variable intake valve and actuator closes one side of the air intake.
When the engine reaches 4000 rpm, the variable intake valve is opened to increase the air passageway. According to Toyota, it was developed to reduce the level of engine noise without the use of a resonator. Although not stated in the Toyota manual, we believe the variable intake valve was also utilized to increase air velocity at lower rpm, which increases the engine's torque output below 4000 rpm.
The dual-stage airbox made things difficult, since any intake system would require removing the variable intake valve and actuator and, therefore, possibly impact low-end power. Still, we elected to install an Injen cold-air intake system on the Celica.
The piping section of the Injen intake is made from 3-inch mandrel-bent aluminum piping, making the system extremely lightweight. The cotton gauze filter is washable and reusable for long-term use. Installing the intake system required the trimming of certain plastic liners around the wheelwell and engine compartment area.
As expected, we lost a couple of horses below 4000 rpm but, at the top end, there were big improvements. Peak power registered 169.2 hp, an improvement of 3.9 hp. With only two performance parts added, the increased power was immediately noticed on the road as the GT-S screamed to redline with each stab of the throttle.
Next, it was time to enhance the Celica's looks. In stock trim, the Celica promotes sharp bodylines with a true sports car stance. To accentuate the bodylines, we decided to install a full Kamanari body kit. The trick five-piece polyurethane kit comes complete with brand-new front and rear bumpers, side skirts and a carbon-fiber rear wing. We also added a Fiber Images direct replacement hood.
The Toyota's lowered stance was augmented by adding a set of H&R sport springs, which increased the car's road-holding abilities. The factory rolling stock was also replaced with wickedly stylish Racing Hart Type CRs. Turbo secured the first set of these three-piece, six-spoke wonders that appeared in the country.
Measuring a full 19-inches across, the Racing Harts seductively fill the fenderwells of Project Celica. We especially like the center cap treatment. Yokohama Parada Spec-2 tires are wrapped around the CRs to provide a big contact patch, which we plan to use to the fullest in future issues.
We have only had the car two months and have already received numerous compliments. Next, we plan on pushing the performance envelope to the edge with the addition of a Blitz intercooled supercharger kit (another the first in the United States deal).
We also plan to unleash a battery of interior refinements with the help of Sparco and Stichcraft. Be sure to check out the next installment of Project Celica. It will be one you won't want to miss.
4879 E. La Palma Ave., Ste. 206
Anaheim, CA 92807
DAZZ Motorsports (Racing Hart Distributor)
Dept. THP, 5121 Commerce Dr.
Baldwin Park, CA 91706
Dept. THP, 244 Pioneer Pl.
Pomona, CA 91768
Dept. THP, 12601 Western Ave.
Garden Grove, CA 92841