ACT 2003 Chevrolet Corvette Twin Disc HD Street Kit Clutch Kit
A C5 Corvette with heads, a cam, a blower or a stroker will outgrow the factory single-disc clutch fast, and most owners notice it as slip at the top of third gear or a clutch that fades after a few hard runs. ACT part number T1S-G01 is the Twin Disc Heavy Duty Street kit for the LS-powered Corvette. This listing is cataloged for the 2003 model year, the 50th Anniversary car, and ACT's chart carries the same kit across a much wider range of GM cars, covered below.
The kit stacks two 10.5 inch (267 mm) discs and a floater under one pressure plate. Doubling the friction surfaces gives T1S-G01 a rating of 891 ft-lb at the crank, which ACT lists as 86 percent over the original clutch, and it also spreads heat across more material for longer life. The rigid-hub street discs use a high-copper organic material for heat transfer, bonded to a steel backing for burst strength, on a heat-treated chrome-moly hub for the 1.125 inch input shaft.
ACT's Positive Lift Floater System lifts the middle plate on release without posts, so there is no floater rattle and nothing to wear. The assembly adjusts for disc wear and releases both discs evenly. ACT says this kit includes its Prolite flywheel, CNC machined and dynamically balanced, along with the pressure plate, both discs, floater and an alignment tool. Some ACT twin kits also include pilot and release bearings, so check the contents before ordering extras. The kit weighs 41.1 lb.
Do a fourth-gear pull from around 2,000 rpm at wide-open throttle and watch whether the tach runs ahead of road speed. If it does, the clutch is slipping. Rule out the hydraulics first: low or dark clutch fluid and a leaking slave can keep the clutch from fully clamping or releasing. Use our slipping diagnosis guide to work through the checks, and the manual versus automatic repair cost guide to budget the job, since the C5's rear-mounted transaxle makes clutch work labor intensive.
Our listing is for the 2003 Chevrolet Corvette with the six-speed manual, which on the C5 is the T-56. ACT's application chart lists T1S-G01 for 1997-2004 C5 Corvettes including the Z06, 2005-2013 C6 Corvettes including the Z06 and Grand Sport, 2010-2015 Camaro SS and the 2014-2015 Camaro Z/28, and the 2004-2006 Pontiac GTO. The chart does not list the C6 ZR1, so ZR1 owners should not order this kit. If your car has a swapped gearbox or non-stock flywheel bolt pattern, send us the year, engine and last 8 of the VIN. Want a harder race clutch for the same cars? See the ACT MaXX XT twin disc race kit, or the ACT Mod-Twin XX for LS Camaro and Corvette with sprung discs. More clutch kits are in our rebuild kits department.
| Brand | ACT |
| Part number | T1S-G01 |
| Fits | ACT 2003 Chevrolet Corvette Twin Disc HD Street Kit Clutch Kit |
| Vehicle fitment | Chevrolet Corvette (2003) |
| Type | Clutch Kits - Multi |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
ACT's chart lists T1S-G01 for 2005-2013 C6 Corvettes including the Z06 and Grand Sport. The ZR1 is not on the chart. Send us your VIN if you want it double checked.
Yes. ACT notes this kit includes its Prolite flywheel, along with the pressure plate, two discs, floater and alignment tool.
ACT rates T1S-G01 at 891 ft-lb at the crank, 86 percent over the original equipment clutch.
ACT describes the feel as light pedal effort and smooth engagement with OE to mild gear rattle, and the floater design is made to avoid floater rattle.
Yes. For organic street discs ACT recommends 300 to 500 miles of mild engagement, such as city driving, before racing or spirited driving.
