Match your genoa car and track to your boat's length and headsail area, not just brand preference: 22 mm systems suit boats to about 28 ft, 27 mm to about 35 ft, and 32 mm up to roughly 46 ft. MAURIPRO stocks genoa cars and tracks across Harken and Antal sized to each range, plus the control blocks and end fittings to trim them from the cockpit.
Genoa cars and tracks come up as a real, recurring buyer question because there's no single "right" answer printed on the box — the correct size depends on your boat's length, your headsail's area, and whether you want to adjust the lead from the cockpit under load or ease the sail first. Get it wrong and you either overpay for hardware your rig will never load up, or you undersize a car that deforms or seizes the first time you're overpowered.
This is written for the 30–45 ft cruiser or performance-cruiser owner replacing tired sheet tracks or upgrading from pin-stop cars to something you can trim on the fly. We'll walk through sizing by boat length and sail area, the ball-bearing-vs-slider trade-off, a compatibility trap that catches a lot of DIY installs, and how to size the control line itself.
Genoa car and track systems at a glance
| System size | Typical boat length | Car style | Adjustable under load? | Example (MAURIPRO) |
|---|---|---|---|---|
| 22 mm (Small Boat) | Up to ~28 ft | Pin-stop slider | No — ease sail first | Harken Slider Car 7/8 in (22.0 mm) – Pinstop ($215.95) |
| 27 mm (Midrange) | ~26–35 ft | Ball-bearing, control-block adjustable | Yes | Harken Genoa Car – Adjustable CB, 27 mm, 2:1 Sheave ($726.95) |
| 32 mm (Big Boat) | ~34–46 ft | Ball-bearing ESP, control-block adjustable | Yes | Harken Genoa Car – ESP Adjustable, 32 mm, 4:1 Sheaves ($1,161.95) |
| 32 mm / 1¼ in T-Track | ~34–46 ft (retrofit) | Slider, fits existing T-Track | No — ease sail first | Antal T-Track – Simple Slider (32 mm) ($155.00) |
What size genoa car and track does my boat actually need?
Start with boat length, then check it against your headsail's area. Harken, the market's reference brand for this hardware, sizes its genoa lead systems in 22 mm, 27 mm, 32 mm, 42 mm and 64 mm profiles and recommends the 22 mm Small Boat system for boats up to about 28 ft, the 27 mm Midrange system for roughly 26–35 ft, and the 32 mm Big Boat system for about 34–46 ft — larger yachts step up to 42 mm and 64 mm Maxi systems. SAIL magazine's own track-replacement writeup confirms the same bands independently.
Boat length is the starting point, not the final word: the load on the car and track actually comes from your headsail's area and the apparent wind you carry it in, so a boat with an unusually large overlapping genoa can outgrow its "by-length" system size. If you're unsure, size up rather than down — the cost difference between adjacent sizes is real, but a car that deforms under an unexpected gust is a mid-season failure, not an inconvenience.
Should I run a ball-bearing car or a slider/pin-stop car?
This is the real fork in the decision, more than brand. A ball-bearing car rides on recirculating bearings and can be trimmed from the cockpit under full sheet load — pull the control line and the car moves, no need to luff the sail first. The trade-off is cost and track compatibility: ball-bearing cars require the manufacturer's own proprietary track, so if you're retrofitting an older boat, you're replacing the track as well as the car, not just the car.
A slider or pin-stop car is the budget alternative. It's held in place by a spring- or screw-pin that drops into holes along the track, it's usually a fraction of the cost of a ball-bearing system, and — critically — it fits your boat's existing T-Track, so there's no track-replacement expense. The catch: you generally can't move a pin-stop car under load. You have to ease (or furl in) the genoa enough to unload the car before it will slide, then reset it and re-sheet. For a cruising boat that changes sail plan a few times a day, that's a minor chore; for a boat that's constantly adjusting for wind shifts, it gets old fast.
From our rigging bench: most of the upgrade requests we get aren't "my car broke" — they're "I'm tired of going forward to move the sheet lead every time the wind shifts." That's a ball-bearing conversation, not a car-replacement conversation, and it's worth being honest with a customer that the track has to come with it.
Does it matter if my existing track is metric or imperial T-Track?
Yes, and this is the compatibility trap that catches the most DIY installs. European brands — Harken, Lewmar, Antal, Ronstan, Selden — build to metric T-Track dimensions; some American-built boats carry imperial ("English") T-Track instead. The two look similar at a glance, but the fastener spacing and the thickness of the T-shaped crossbar differ, and most metric cars will physically fit imperial track (though not always vice-versa). Before you order a slider car for an existing track, confirm which standard your boat actually has — pulling one car off the track and measuring it, or checking your rigger's records, beats guessing from a spec sheet.
Ball-bearing systems remove this ambiguity because you're replacing the track and the car together as a matched set from one manufacturer — but if you're only swapping the car and keeping the track, the metric/imperial check comes first, before you add anything to cart.
How much control-line purchase and what line diameter do I need?
If you're going the ball-bearing, cockpit-adjustable route, the control-line purchase and diameter matter as much as the car itself. As a starting point, the load on the control line runs to roughly 30% of the genoa car's load when the sheet lead deflects the control line 45°, and roughly 50% at a 60° deflection — so the sharper the lead angle back to the car, the harder the pull. Modular control-block kits (2:1, 3:1, or 4:1) let you dial in the mechanical advantage you actually need rather than muscling a 2:1 system in a breeze.
For line diameter, the rule runs the opposite direction from what most sailors expect: use the largest-diameter control line your car's sheave is rated for, not the smallest. A thinner line is easier to coil but adds friction and grip trouble under load; the biggest line the sheave will accept gives the smoothest, lowest-friction pull. Keep the lead itself clean, too — a control line that fouls on a cam cleat or rubs the traveler beam quietly eats into the purchase you just paid for.
Which should I choose?
If your boat is under about 28 ft, or you're on a tight budget and don't mind easing the sail to adjust, a 22 mm pin-stop slider on your existing track is the practical, low-cost choice. If you're in the 26–35 ft range and want to trim the lead from the cockpit without leaving the wheel, step up to a 27 mm ball-bearing car — that's the size class where the control-block purchase genuinely pays off. Boats from about 34–46 ft with bigger overlapping genoas want the 32 mm Big Boat system, sized to the higher loads a large headsail actually generates. And if your existing T-Track is sound and you just want to shed a stuck pin-stop car, a same-size slider like Antal's T-Track Simple Slider is the cheapest fix that doesn't touch the track at all.
Common mistakes when choosing a genoa car and track
- Sizing by boat length alone. Length is a starting point; an unusually large overlapping genoa can push a boat into the next system size up regardless of LOA.
- Buying a ball-bearing car without budgeting for new track. Ball-bearing cars need the manufacturer's proprietary track — the car alone won't retrofit onto an old pin-stop T-Track.
- Assuming metric and imperial T-Track are interchangeable. They look alike; fastener spacing and crossbar thickness differ. Confirm before ordering a slider car for existing track.
- Undersizing the control line for "easier handling." A thinner line feels handier off the reel but adds friction under load — use the largest diameter your sheave accepts.
Frequently asked questions
What size genoa car do I need for a 35-foot sailboat?
A 35-footer typically sits right at the top of Harken's 27 mm Midrange range (about 26–35 ft) or the bottom of the 32 mm Big Boat range (about 34–46 ft). If your genoa is a large, overlapping sail, size up to 32 mm; a smaller working jib on the same hull can stay in 27 mm.
Can I put a ball-bearing genoa car on my existing T-Track?
Generally no — ball-bearing cars need special recirculating track from the same manufacturer. A handful of exceptions exist in the market, but as a rule, budget for track and car together when moving to ball bearings.
Is a 32 mm genoa track the same as 1¼ in T-Track?
They're close but not identical. Metric 32 mm track and 1¼ in imperial T-Track differ in fastener spacing and crossbar thickness; most metric cars will fit imperial track, but confirm before assuming compatibility either direction.
Do I need to ease my genoa to move a pin-stop car?
Yes. Pin-stop and slider cars lock into holes along the track and are designed to move only once the sheet load is released — ease or partially furl the genoa first, then reposition.
Does MAURIPRO carry genoa cars for other brands' tracks?
Yes — MAURIPRO stocks genoa cars and matched tracks from Harken and Antal across the 22, 27, and 32 mm size classes, plus slider cars sized to fit existing T-Track.
The genoa cars below are active in our catalog across the size range covered above.
Harken Slider Car 7/8 in (22.0 mm) – Pinstop — the budget small-boat pick for boats to about 28 ft on existing track.
Harken Genoa Car – Adjustable CB, 27 mm, 2:1 Sheave — cockpit-adjustable ball-bearing car for the 26–35 ft midrange.
Harken Genoa Car – ESP Adjustable, 32 mm, 4:1 Sheaves — the big-boat ball-bearing system for 34–46 ft boats with larger genoas.
Antal T-Track – Simple Slider (32 mm) — a low-cost slider that retrofits onto existing 32 mm / 1¼ in T-Track.
You may also be interested in
- Adjusting Genoa Lead Cars
- Travelers, Tracks & Genoa Cars — Tracks
- Where to Buy Lewmar Genoa Car and Traveler Replacement Parts
Written by the MAURIPRO Rigging Team. MAURIPRO Sailing has outfitted cruisers and racers since 2003 — competitive sailors and marine specialists who spec and install this hardware on our own boats, not just in a catalog. Last updated 2026-08-26.