ACT 1999 Acura Integra HD/Race Sprung 6 Pad Clutch Kit
The ACT AI4-HDG6 is the entry point to a ceramic puck clutch for the B-series Integra. It pairs ACT's Heavy Duty pressure plate with a six-pad, spring-centered race disc, and ACT rates it at 310 ft-lb at the crank, 68 percent over the factory clutch. It is aimed at the 1999 Integra GS-R, LS or Type R that now has intake, header, cams or a light turbo and keeps cooking an organic disc at the drag strip or autocross, while the owner still wants a pedal close to stock.
The stock Integra clutch is a full-face organic disc under a pressure plate sized for roughly factory torque. The HDG6 changes both halves. The H025 Heavy Duty plate uses ACT's own diaphragm design to raise clamp load and reduce deflection, and the 220 mm (8.7 in) disc replaces the full friction ring with six ceramic pads that tolerate far more heat. The sprung center damps torsional vibration, so launches are less harsh on the axles and gear rattle stays near stock. ACT describes the feel as light to moderate pedal effort with aggressive engagement, and its FAQ puts the Heavy Duty plate at 15-40 percent more effort than stock. Compared to the ACT AI4-XTG6 Xtreme kit, which uses the same disc with a stiffer plate for 410 ft-lb, the HDG6 is the better choice when your power level does not need the extra clamp and you drive the car on the street.
Integras from 1994 to 2001 use a cable clutch. A cable adjusted with no free play holds the bearing on the fingers and causes slip on any clutch, so check pedal free play first. Then make a full-throttle pull in fourth from about 3,000 rpm. If the tach jumps without the car pulling harder, the disc is slipping. Look for oil on the bellhousing seam as well; a leaking crank seal or input seal will soak new pads. Our slipping diagnosis guide walks through the load test, and the clutch slipping causes page covers the non-clutch causes.
Our listing is titled for the 1999 Acura Integra. ACT's application chart for AI4-HDG6 covers 1994-2001 Integra 1.8L (B18B1, B18C1, B18C5) five-speeds including the GS, GS-R, LS, RS, Special Edition and Type R, the 1994-1997 Civic del Sol VTEC, 1999-2000 Civic Si and 1998-2001 CR-V EX and LX. D-series and K-series transmissions take different kits. Swapped cars should match the gearbox, not the chassis, so send us the year and VIN or the engine and transmission codes if you are unsure. Browse the full clutch and rebuild kit collection, or step down to the organic ACT AI4-HDSS street kit if the car is a daily driver.
The kit weighs 13.2 lb per ACT. No flywheel is included; ACT sells the 600105 Prolite and 600110 Streetlite separately.
| Brand | ACT |
| Part number | AI4-HDG6 |
| Fits | ACT 1999 Acura Integra HD/Race Sprung 6 Pad Clutch Kit |
| Vehicle fitment | Acura Integra Hd/Race Sprung 6 (1999) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
ACT lists it for 1994-2001 Integra 1.8L B18B1, B18C1 and B18C5 five-speeds including the Type R, plus 1999-2000 Civic Si, 1994-1997 del Sol VTEC and 1998-2001 CR-V. Send the year and VIN if you want us to confirm.
ACT rates the AI4-HDG6 at 310 ft-lb at the crank, 68 percent over the factory clutch. If your build is past that, look at the XTG6 (410 ft-lb) or XXG6 (485 ft-lb).
It is drivable, and the Heavy Duty plate keeps pedal effort light to moderate, but six ceramic pads engage abruptly and are harder on stop-and-go traffic. ACT recommends it for high horsepower street or race use. A pure commuter is better served by the organic HDSS kit.
The release and pilot bearings are in the kit. Plan on resurfacing or replacing the flywheel, and check the fork, pivot ball and cable while the gearbox is out.
Most 1994-2001 Integras use a cable clutch, so there is nothing to bleed. Set cable free play after the install. Hydraulic-release models on ACT's chart are bled with fresh brake fluid.
