Ford Forums banner

1 - 1 of 1 Posts

·
Registered
Joined
·
7,859 Posts
Discussion Starter #1
Tuner: Acosta Motorsports Mazda RX-8

This Is Hard-Core: Meet the world’s first three-rotor RX-8

RICHARD CHANG/AUTOWEEK


ACOSTA MOTORSPORTS MAZDA RX-8
POWERTRAIN: 400-hp, 350-lb-ft twin-turbocharged three-rotor; rwd, six-speed manual
CURB WEIGHT: 3279 lbs (est.)
0 TO 60 MPH: 3.0 seconds (est.)

In the quiet suburb of Wallington, New Jersey, Acosta Motorsports (acostamotorsports.com) is an unlikely storefront. Ten years ago, after years of tuning street-class drag cars for friends and neighbors, Marcos Acosta got serious about racing. He dropped a rare Mazda 20B-REW twin-turbo three-rotor into a tubbed-out Mazda MX-3. He converted the car to rear-wheel drive and installed a G Force air-shift transmission.

The project took Acosta more than three years to finish. When he was done, the short-wheelbase car packed more than 1100 hp and was capable of seven seconds in the quarter-mile, or a second shy of an NHRA Pro Stock car. Acosta also gained a reputation for heart-stopping launches that came close to acrobatics.

These days Acosta races a tube-chassis Mazda truck constructed by famed chassis-builder Jerry Bickel. Also powered by a 20B, the truck sits pushed up against the wall of a garage that is packed like a crab tank in Chinatown. A Porsche 911, Nissan 300Z and Mazda RX-7 sit wheel to wheel, all in curious stages of mid-surgery. The RX-7 has its hood up, revealing a Nissan RB25DET taken from a Skyline GT-R. The Porsche is getting a T66 dual-ball-bearing turbo setup, good for 535 hp at the wheels. In other words, you don’t come here for a salad.



Mazda introduced the powerful three-rotor 20B-REW in the Eunos Cosmo in 1990, which was sold exclusively in Japan and came only as a twin-turbo (the W in the engine designation stands for “double turbo�). Production of the Cosmo ended in 1995, but the 20B lived on as the ultimate swap for Mazdaheads everywhere. When Acosta’s son, Acosta Jr., who runs Acosta Motorsports with his father, decided to build up a 2004 RX-8 last year, it was the only engine considered.

“We took the motor out of the truck,� says Acosta Sr., referring to his NHRA dragster, “and put it inside the RX-8. That motor is prepped for more than 1200 hp. That motor was ready on the inside. It’s got lightened rotors, balanced everything, apex seals, the porting—you’ve got high power on low boost. And you’ve got power for life.�

According to Acosta Jr., the 20B-powerÂ*ed RX-8 is the first of its kind. The twin-turbo setup was replaced by a custom-built Garrett T78 turbo by Phoenix Turbo (cheapturbo.com) that features a GTQ turbine. Acosta Motorsports designed the rest of the system—from the turbo manifold to the downpipe and intercooler.



Acosta Jr. handled the wiring and electrical on the car. He also fine-tuned performance of the 20B with a Microtech engine management system and a laptop. “I can switch from the 10 psi program [400 hp] to the race program with just a touch of the keyboard,� he said.

Unlike the RX-7’s 13B twin-rotor engine, the 20B grooves with more bass. At idle it can sound like six pistons joggling to high-profile cams, like a tuned twin-turbo Supra or even a Ford small-block. Under full boost it’s joined by the high whistle of the spinning turbo.

Even though boost comes on around 3000 rpm, heavy traffic on our test drive spoiled the party. Occasions to savor long-lasting boost speed are rare. But when they did come along, Acosta Sr., sitting squat behind the wheel, squeezed every last ounce out of them.

Even without turbo boost, the rear wheels spin and chirp through second and third gears—though the car never seemed to twitch or veer off balance. Acosta Motor-sports has tuned the suspension only slightly; with JIC coilovers and some bar work front and back, top and bottom. That’s about as far as they’re going to go.

Asked about track times and top-speed possibilities, Acosta Jr. shakes his head. “If we start going to the track,� he says, “we’ll really get into it and put on roll cages and all sorts of things. But maybe we’ll do one pass, then be told to go home.�
 
1 - 1 of 1 Posts
Top