Cavitation Plate FAQ
The most common questions we get from Torqeedo, ePropulsion and Momentum owners — answered by the team at e-marine.at, Austria’s biggest Torqeedo partner. New to the topic? Start with our complete guide to cavitation plates for electric motors.
What is the difference between cavitation and ventilation?
Cavitation occurs when extreme low pressure causes water to boil into vapor bubbles, which implode and erode the propeller metal. Ventilation occurs when surface air or exhaust gas is drawn down into the spinning propeller, causing a sudden loss of grip and motor over-revving. A cavitation plate primarily prevents ventilation.
Is a cavitation plate the same as an anti-ventilation plate?
Yes. Cavitation plate, anti-cavitation plate, anti-ventilation plate, ventilation plate and cav plate all describe the same component — a flat barrier above the propeller that blocks surface air. Anti-ventilation plate is the technically correct term; cavitation plate is the one almost everyone uses. In German you will also see Kavitationsplatte, Antikavitationsplatte and CAV-Platte. A hydrofoil, however, is a genuinely different product. We break down where each name comes from in our complete guide.
Do cavitation plates increase a boat’s speed?
Yes — in real-world conditions. A cavitation plate doesn’t generate artificial lift like a hydrofoil; it increases speed by eliminating losses. The propeller stays in solid, unaerated water, so thrust isn’t lost in turns, chop or under heavy load — many owners report easier planing and higher, more consistent speeds.
Are clamp-on cavitation plates safe for saltwater?
Yes. High-quality clamp-on plates made from V4A (AISI 316) marine-grade stainless steel are designed to resist saltwater pitting. Because they clamp on with padded 3M isolation instead of drilling into the aluminum housing, the factory paint stays intact and the galvanic corrosion path is avoided.
How high above the propeller should a cavitation plate be mounted?
The recommended mounting height is 1.5 to 2 cm above the propeller, measured from the tip of the cavitation plate, with the plate tilted slightly downwards. This angle pushes the water stream down onto the propeller and blocks surface air most effectively.
Do I need to drill holes in my electric outboard?
No. The plate uses a clamp-on design: two halves are joined around the shaft with self-locking bolts, and the inside is lined with padded 3M adhesive tape. Installation takes minutes with a 5.5 mm wrench and a 2.0 mm hex screwdriver — and leaves no trace on the motor. The only exception is the Prop Guard: there, the supplied cavitation plate itself is drilled so the guard cage can be bolted to it. The outboard is still never drilled.
What is the difference between a hydrofoil and a cavitation plate?
A hydrofoil is a curved wing that generates lift to push the stern up — useful for heavy combustion boats getting on plane, but it adds parasitic drag. A cavitation plate is a flat, zero-camber barrier above the propeller that prevents ventilation without lift, which is why it suits efficiency-focused electric outboards.
Which cavitation plate fits my motor?
Each plate is engineered for a specific model family: Torqeedo Travel 2024 and newer, Torqeedo Travel up to 2023 / ePropulsion Spirit 1, Torqeedo Cruise 2.0–6.0 (Standard or Big Plate), ePropulsion Spirit 2 and Momentum U2. If you are unsure, contact us via WhatsApp with your motor model and we will confirm the right fit.
Will a cavitation plate damage or modify my motor?
No. Because the plate clamps on over padded 3M tape rather than being bolted through the housing, the outboard is not drilled, glued or permanently altered. The plate can be removed at any time without leaving marks. If in doubt about your manufacturer’s warranty terms, check them before installation. With the Prop Guard it works differently: the cavitation plate supplied with it is drilled so the guard cage can be bolted on, so that plate and cage stay together as one unit. Even then, nothing is drilled into the outboard.
Does a cavitation plate help at slow, displacement speeds?
Yes. Electric outboards typically run at displacement speeds where every watt counts. By stopping air intrusion and turbulence around the propeller, the plate reduces wasted energy, so more battery power converts into forward thrust — which shows up as noticeably more range per charge.
Does the Prop Guard have to be drilled into the motor?
No. Nothing is drilled into the shaft or the housing of the outboard. The guard cage is bolted to the V4A stainless cavitation plate that is supplied with it, and that plate is the part that gets drilled. The motor stays untouched.
Can I still use the cavitation plate on its own after fitting the Prop Guard?
No. Once the plate has been drilled for the cage, plate and guard stay together as one unit and are used in combination. If you want a plate you can run on its own, choose a standalone cavitation plate instead.
What does a propeller guard actually protect against?
It protects people and animals from the turning propeller: recovering someone from the water, swimming off the anchorage, a dog or a child on board. It is not an impact guard. It does not protect the drive if you hit a solid obstacle or run aground.
Which motors does the Prop Guard fit?
There are three versions: Torqeedo Travel 2024 and newer, Torqeedo Travel 2023 and earlier together with the ePropulsion Spirit 1, and Torqeedo Cruise 2.0 to 6.0. Pick the matching version on the Prop Guard product page, or send us your motor model on WhatsApp and we will confirm the fit.
Still have a question?
Message us directly on WhatsApp — we answer personally and usually within the day. Or browse the full collection of V4A cavitation plates. Free worldwide shipping · 30-day risk-free returns.
