Innovative Mounts 12-15 Civic Si Mount Kit K24Z7

Innovative Mounts 12-15 Civic Si Mount Kit K24Z7

Your 9th-gen Civic Si has 205 horsepower, a six speed, and factory mounts full of fluid that let the K24Z7 rock like it's on a hinge every time you drop the clutch. That rocking is the wheel hop you feel launching from a light and the slop you feel between gears. The Innovative Mounts 12-15 Civic Si mount kit replaces all three engine mounts on the FB6 sedan and FG4 coupe with solid-bushing units that stop the motor moving and hand the drivetrain slack back to you.

What It Is and Why It Works

Honda's OEM mounts on this car are hydraulic. There's a fluid chamber inside them that damps engine vibration for comfort, and it does that job well. It also means the engine is floating on a soft, compliant mount, so under load the K24Z7 twists on its axis, the axles change angle, and the front tires load and unload. That's wheel hop. Innovative removes the fluid chamber entirely and replaces it with a polyurethane bushing. The motor stays put.

What you feel afterward: the car pulls straight off a launch instead of chattering, shifts land cleaner because the engine isn't lurching back and forth between them, and throttle response feels immediate rather than rubbery. What you also feel: more engine vibration through the shifter, the pedals and the seat, and more engine noise in the cabin. Firmer mounts always transmit more, never less. Anyone who tells you a polyurethane mount reduces vibration compared to the factory fluid mount is describing the opposite of what physics does. On a 9th-gen Si the vibration lives mostly at idle and in the 1,200 to 3,000 rpm range, and it eases somewhat over the first month as the bushings seat.

The kit comes two ways and this is the choice that matters most. The steel version (part 91250) uses welded steel housings. The billet version (B91250) uses CNC-machined aluminum housings. Both use the same polyurethane bushings and both replace the same three mounts, so the driving difference between them is small. Billet is stiffer and lighter and looks like a build piece under the hood; steel does the same job for less. If this is a street car with occasional canyon or autocross duty, steel does everything you need. If you're building the bay and want the mounts to match, take the billet.

The other choice is bushing durometer. Innovative rates 75A for roughly 250 to 400 horsepower, 85A for 400 to 500, and 95A for 500 and up. A stock or bolt-on K24Z7 makes nowhere near those numbers, so on this platform durometer is really an NVH choice rather than a strength one. Higher durometer means more harshness, full stop.

Specs

Available Options

Fitment

Si only. Innovative specifies the K24Z7 engine and transmission and nothing else, so the 2012-2015 non-Si Civic with the R18 does not fit, the automatic does not fit, and a K24Z7 swapped into a different chassis does not fit either. If your car is a 2012-2015 Civic Si with the factory six speed, you're in the right place.

What to Know Before You Buy

Pick your durometer for how you drive, not for how much power you wish you had. On a car making stock-ish K24Z7 numbers, 85A and 95A do not make the car faster than 75A; they just make it louder. Most 9th-gen Si owners running these daily land on 75A and stay happy. Go 85A if the car sees regular track time and you have already accepted a stripped interior. 95A belongs on a car with a cage.

Doing all three mounts at once is the right call and it is also why this kit exists as a kit. Mixing one stiff aftermarket mount with two soft factory mounts concentrates load on the new one and, in practice, produces more vibration than a matched set of three at the same durometer. If the budget only covers one mount, do the rear first, because that is the one carrying torque reaction on this platform.

You'll reuse all of your OEM hardware, and the kit adds two grounding tabs, bushing hardware and one long bolt. Do not lose the grounding tabs. The factory mounts carry ground paths on this chassis, and skipping the tabs shows up later as weird sensor and charging faults that nobody connects back to a mount install. Leave everything finger tight until all three mounts are located and the engine is sitting naturally, then torque, so you're not preloading a bushing.

Two things to be honest about before you order. First, this is a job most people should hand to a shop. It is not difficult but the engine has to be supported the whole time. Second, Innovative will not accept mounts back once they've been bolted down and show bolt impressions, so verify your car is a K24Z7 manual Si before anything gets torqued.