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beautifullyengineered:

The Honda Integra Type-R (DC2) is Beautifully Engineered

Type-R: Honda’s Racing Spirit

Engine

The Type R’s B18C5 engine was not merely a tuned version of the GS-R’s B18C. The Type-R’s head is a re-worked PR-3 head, with better valves, camshafts, stiffer valve springs and a red valve cover. During production, the B16A head would get a green marker line to signify a ‘Hand porting’. Molybdenum-coated, high compression pistons and stronger-but-lighter connecting rods strengthened the reciprocating assembly. Extra counter-weights were installed on the crankshaft which altered its vibration modes to enhance durability at high rpm. The intake valves were reshaped with a thinner stem and crown that reduced weight and improved flow. Stiffer valve springs resisted float on more aggressive camshafts. Intake air was now drawn from inside the fender well, for a colder, denser charge. That intake fed a short-runner intake manifold with a larger throttle body for better breathing. An improved stainless steel exhaust collector with more gentle merge angles, a change to a larger, consistent piping diameter, flared internal piping in the muffler allowed easier exit of gases. A re-tuned engine computer also contributed to improved power output, which allowed the Type-R to accelerate from 0 to 60 mph (100 km/h) in 6.9 seconds (as opposed to the GS-R’s 7.0) and reach a top speed of 135 mph.

Transmission

The transmission gearing used was very similar to that of the Civic Si from 1999 to 2000, which featured closer gear ratios in second through fifth gears, in order to take advantage of the additional rev range. However, the Type R transmissions featured stronger synchros in all 5 gears. The North American version retained the same 4.4 final drive throughout the Type-R’s production run. The Japanese version changed to a 4.785 final drive in 1998 along with revised gearing, but maintained the 4th and 5th gears from the GS-R transmission for easier cruising at higher speeds. Unlike the other model Integras with an open differential, the Type R came with a torque-sensing limited slip type.

Chassis

The chassis received enhancements in the form of reinforcements to the rear wheel wells, roof rail, and other key areas. “Performance rods”, chassis braces that were bolted in place, were added to the rear trunk wall and sub-frame. The front strut tower bar was replaced with a stronger aluminum piece. Honda marketed a rear strut tower bar as a dealer accessory as well, but it required cutting of the damper mount access panels. Camber rigidity was improved at the rear by increasing wheel bearing span by 10 mm (0.4 in). This rigidity was further improved in 1998 when the smaller upper suspension link was changed from a stamped steel part to a fabricated part with a more rigid bushing. The Type-R’s body also received a new functional rear spoiler, body-colored rocker panels and front lip, and 5-bolt hubs with special lightweight Type-R wheels. Under those wheels was a much larger set of disc brakes, front and back. The tires were upgraded to Bridgestone RE010 summer tires.

Suspension

The Type-R received very aggressive tuning in its suspension settings. All soft rubber bushings were replaced with much stiffer versions, as much as 5.3 times higher in durometer readings. The springs and dampers were much stiffer, with a 15 mm (0.6 in) reduction in ride height. The rear anti-roll bar diameter was initially increased to 22 mm (0.9 in) in diameter, and further enlarged to 23 mm (0.9 in) in diameter in the 1998 JDM model. The front anti-roll bar sized at 24 mm (0.9 in) for USDM models and 25 mm (1.0 in) for the 1998 JDM models. The end links were changed to a more responsive sealed ball joint as opposed to a rubber bushing on the lesser models. The result was a chassis with very responsive, racetrack-ready handling that ably absorbed mid-corner bumps. Mild oversteer was easy to induce with a lift of the throttle, and during steady-state cornering the car maintained a slight tail-out stance.

Interior

The interior was stripped down to reduce weight. The air conditioning system was optional in early models and nearly all the sound-dampening material was eliminated. This provided for a much noisier ride, but since the Type-R was marketed as a race car for the street, most owners didn’t mind. The seats were also unique to the Type-R. For the U.S. market, the upholstery was done in Alcantara and mesh, with the bottom cushion made softer than the standard Integras to preserve comfort. The Japanese market cars used Recaro SRII seats—a slightly smaller variant of the Recaro SRD.

Performance

• Edmund’s Insideline tested a 12-year-old stock Type R: 0-60 in 6.8 seconds, 1/4 mile in 14.9 seconds @ 95.2.
• MotorTrend clocked the Type R at: 0-60 in 6.2 seconds, 1/4 mile in 14.8 @ 96.3.
• Sports Compact Car clocked theirs at: 0-60 in 6.1 seconds, 1/4 mile in 14.5 @ 96 MPH

The JDM Type-R ‘98 spec’ is quicker off the line and through low-speed turns than the ‘96 spec’, due to the higher torque provided by the 4 to 1 header and lower final drive ratio of 4.7853. The 96 and 98 spec are about dead even in the 400 meter(1312 feet)drag race. The 96 is lighter, and has approximately the same overall 3rd and 4th gear ratios. Reported times of 14.2 in the 400 meter.

• In-depth analysis of Type-R v. GS-R specification

Downloads:

• 1997 Integra Type-R Technical Guide (Book scans - PDF)
• 2000 JDM Integra Type-R Sales Brochure (Book scans - JPEG)

Video:

• Best Motoring International #1: Type-R Legend (Youtube playlist, 6 parts)