Clutch Masters 12-13 Honda Civic Si 2.4L 6spd FX350 High Rev Sprung Clutch Kit w/ Steel Flywheel
This Clutch Masters FX350 kit is for the ninth-generation Honda Civic Si with the 2.4L K24 and six-speed manual, sold as 08320-HRFF-SK with the matching OEM-weight steel flywheel included. It is built for the Si owner who has gone past bolt-ons, with cam and head work, a medium-boost turbo or supercharger, or nitrous, and whose clutch now slips on a hard pull in the upper gears. It is a street kit that can also handle the occasional track weekend, and because the flywheel matches factory weight, it does not need a reflash.
The FX350 uses Clutch Masters' Power Plus I high-leverage pressure plate over a heavy-duty segmented disc faced with steel-backed Fiber-Tough material, a sprung hub and a Marcel spring wafer. Clutch Masters rates it at a 110 percent increase in holding capacity over stock and places it just above the FX300 in grip. The cost of that grip is engagement: the FX350 bites more aggressively than the FX300 and Clutch Masters says it can chatter some, which matters if the car spends most of its life in traffic.
Clutch Masters builds all of its K24 Si clutches as conversion kits, and the stock flywheel will not work with them. The 08320 kits are designed around the FW-320-SF steel flywheel, which is held to OEM weight, so the factory ECU keeps working without a Hondata FlashPro. That is the difference between this kit and the 08240 version, whose lighter flywheel needs a tune to keep the check engine light off. The SK version ships the FW-320-SF with the clutch.
Slip-test the car in fourth from roughly 2,000 rpm at full throttle and watch the tach against the speedometer. Inspect the bellhousing seam for oil from the rear main seal and check the clutch master and slave for leaks, since contamination or a hydraulic release problem will ruin a new disc. Our slipping diagnosis guide walks through separating clutch slip from other faults, and shift flare vs slip explains what true slip looks like on the tach.
Our listing is titled for the 2012 to 2013 Civic Si 2.4L six-speed. Clutch Masters' application data for the 08320-HRFF FX350 covers the 2012 to 2015 Civic Si 2.4L six-speed, the 2009 to 2014 Acura TSX 2.4L six-speed and the 2013 to 2015 Acura ILX 2.4L six-speed. If your car already has an aftermarket flywheel or a different clutch conversion, tell us what is in it, and send the year and VIN if you want a fitment check. If you want the clutch with a lighter flywheel and you already run a FlashPro, the FX350 kit with lightweight flywheel is the same clutch on the 08240 platform. More kits are in our rebuild kits category.
| Brand | Clutch Masters |
| Part number | 08320-HRFF-SK |
| Fits | Clutch Masters 12-13 Honda Civic Si 2.4L 6spd FX350 High Rev Sprung Clutch Kit w/ Steel Flywheel |
| Vehicle fitment | Honda Civic Si (2012-2013) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
No. Clutch Masters builds the 08320 kits around the FW-320-SF steel flywheel, which is held to OEM weight, so the factory ECU works without a tune. The 08240 FX350 kit with the lighter flywheel is the one that needs a FlashPro.
Both are rated at a 110 percent holding increase, but Clutch Masters gives the FX350 Fiber-Tough disc slightly more holding capacity and more aggressive engagement, with some chatter. The FX300 is the smoother street choice; the FX350 suits cams, medium boost or occasional track use.
No. Clutch Masters says the stock flywheel will not work with its K24 Si clutch kits. This SK kit includes the correct FW-320-SF flywheel.
Our listing title says 2012 to 2013, but Clutch Masters lists the 08320-HRFF for 2012 to 2015 Civic Si 2.4L six-speed, 2009 to 2014 TSX and 2013 to 2015 ILX. Send your VIN if you want us to confirm.
It can be, but expect a firmer, quicker engagement than stock and possible chatter on take-off. Drivers who mostly commute in traffic are usually happier with the FX300 or FX100.
