The FL5 Type R is a great car out of the box. But if you’ve driven one hard or tracked it, you’ll know the drivetrain feels sloppy under load. The factory rear engine mount is soft rubber. That keeps cabin noise down on the commute, but it lets the engine and trans rock around when you’re pushing the car.
You feel it as wheel hop on hard launches and vague shifts under load. Drive a stock FL5 back-to-back with one that’s had the rear mount sorted and the difference is obvious.
The problem with most aftermarket mounts
The usual fix in the Honda world is a polyurethane mount insert or a full poly mount. They work. Engine movement drops, shifts tighten up, wheel hop improves. But the trade-off is cabin vibration, anywhere from “noticeable” to “really annoying,” especially at idle with the A/C on.
If you’ve been on any FL5 or FK8 forum, you’ve seen it: “My car rattles so bad since I put the motor mount in.” It’s the most common complaint with aftermarket engine mounts across the Honda community.
What PRL does differently
PRL Motorsports went a different direction. Instead of polyurethane, they use two press-fit 60A durometer EPDM bushings in a billet 6061 aluminium housing with an I-beam design.
Why does the bushing material matter? EPDM is denser than polyurethane, so PRL can run a softer durometer rating while still providing more rigidity than the factory mount. Softer durometer means less vibration reaching the cabin. More rigidity means less engine movement under load. You get the performance benefit without the daily driving penalty.
The I-beam core resists bending and stress well (same principle used in performance connecting rods), and the press-fit bushing installation eliminates gaps that cause metallic rattles. The bushing shells are zinc-coated for corrosion resistance too, which matters in Melbourne where salt and weather take their toll.
Poly inserts can mushroom, wallow out, and degrade over time. EPDM holds its shape and properties long-term. There’s a reason OE manufacturers use this type of bushing material from the factory.
What you’ll actually feel
On the street, the difference is subtle but real. Shifts feel more direct and you get more feedback through the chassis. At idle with the A/C running (which is half the year in Melbourne), vibration is minimal once the bushings break in. Nowhere near the harsh buzz you get from a poly setup.
On track or during spirited driving, it’s more obvious. Less wheel hop, crisper shifts, and the whole drivetrain feels more connected. The engine stays put instead of rocking around, and you notice the difference when you’re pushing the car.
It’s also one of the simplest upgrades on the FL5. Car on ramps, drop the undertray (a few screws and quarter-turn fasteners), undo one 19mm bolt and one 17mm bolt, swap the mount. About 30 minutes start to finish.
Our take
We’ve seen a lot of engine mount solutions come through the workshop across FK8s, FL5s, and other K-series Hondas. The PRL rear engine mount is one of the few that actually improves performance without ruining the daily driving experience. Good balance of engineering and practicality, and it’s one of the first mods we recommend for FL5 owners who want to tighten up their drivetrain feel.
If you’re interested in the PRL rear engine mount for your FL5, or you want to chat about where it fits in your build, get in touch with the team at Revzone.
