Donzi 45 ZX 2005 vs Donzi Z-21 1987 - Boat Spec Comparison

Q: Which is the larger boat — the Donzi 45 ZX 2005 or the Donzi Z-21 1987?

The Donzi 45 ZX 2005 is the longer of the two at 45,0 feet overall. The Donzi Z-21 1987 comes in at 21,0 feet, making it roughly 24,0 ft shorter — a meaningful difference in deck room and overall on-water presence.

Q: Which boat can handle a bigger outboard?

The Donzi 45 ZX 2005 is rated to a maximum of 2 550 hp, giving it the larger power ceiling. The Donzi Z-21 1987 tops out at 350 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.

Q: How many people can each boat hold?

The Donzi 45 ZX 2005 is Coast Guard rated for 13 passengers, while the Donzi Z-21 1987 is certified for 6. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.

Q: Which boat has the larger fuel tank — the Donzi 45 ZX 2005 or the Donzi Z-21 1987?

The Donzi 45 ZX 2005 has the bigger tank at 405 gallons, versus 66 gallons on the Donzi Z-21 1987. That 339-gallon difference translates to roughly 1017–1695 nautical miles of additional range at cruising speed, depending on motor, load, and conditions.

Q: Are the Donzi 45 ZX 2005 and Donzi Z-21 1987 from the same manufacturer?

Yes — both the Donzi 45 ZX 2005 and the Donzi Z-21 1987 are built by Donzi. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.

Boat Comparison

Donzi 45 ZX 2005 vs Donzi Z-21 1987

Donzi

Donzi 45 ZX 2005

2005

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Donzi

Donzi Z-21 1987

1987

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Detailed Evaluation & Buyer Recommendation

Donzi 45 ZX 2005 vs Donzi Z-21 1987 — Same Brand, Different Boat

The Donzi 45 ZX 2005 vs Donzi Z-21 1987 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.

The power gap is worth calling out. Rated to 2 550 hp, the Donzi 45 ZX 2005 has a 2 200-hp advantage over the Donzi Z-21 1987's 350-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Donzi 45 ZX 2005 carries 405 gallons versus 66 gallons in the Donzi Z-21 1987. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

For family outings this is probably the sharpest distinction between the two. The Donzi 45 ZX 2005 is rated for 13 passengers, while the Donzi Z-21 1987 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Donzi 45 ZX 2005 could be the deciding factor.

Bottom line: Choose the Donzi 45 ZX 2005 if your priority is putting more people on the water — it handles 13 passengers and at 45,0 ft it has the deck room to back that rating up comfortably. The Donzi Z-21 1987 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.

General Boat Info

MakeDonzi

Makenot available

Model45 ZX

Modelnot available

Model Year2005

Model Yearnot available

Measurements / Dimensions

Beam9 ft. 3 in

Beamnot available

Beam - Meters2.82

Beam - Metersnot available

Beam - Inches111

Beam - Inchesnot available

Deadrise24℃ Z-Tech

Deadrisenot available

Draft [drive up] - Detail32 in. (0.81 m)

Draft [drive up] - Detailnot available

Draft [drive up] meters0.81

Draft [drive up] metersnot available

Draft [drive up] inches32

Draft [drive up] inchesnot available

Draft [max] - Detail47 in. (1.19 m)

Draft [max] - Detailnot available

Draft [max] - Meters1.19

Draft [max] - Metersnot available

Draft [max] - Inches47

Draft [max] - Inchesnot available

Weight - Detail16,000 lbs. (7,258 kg)

Weight - Detailnot available

Weight - kg7257.47

Weight - kgnot available

Weight - lbs.16

Weight - lbs.not available

Length - Meters13.72

Length - Metersnot available

Length - Feet45

Length - Feet21

Length overall - Detail45 ft. 0 in. (13.72 m)

Length overall - Detail21.00 ft

Length overall - Meters13.72

Length overall - Meters6.4

Length overall - Inches54

Length overall - Inches252

Engine and Drivetrain

Fuel tank capacity - Detail405 gal. (1533.1 l)

Fuel tank capacity - Detailnot available

Fuel tank capacity - Liters1533.09

Fuel tank capacity - Liters249.84

Fuel tank capacity - Gal405

Fuel tank capacity - Gal66

Drive typeI/O

Drive typeinboard

Engine max2,550 hp (1901.54 kw)

Engine maxnot available

Engine makenot available

Engine makeMercruizer

Horsepowernot available

Horsepower350 hp

Fuel typenot available

Fuel typeGas

Operational Info

Headroom6 ft. 3 in

Headroomnot available

Sleeping capacity2

Sleeping capacitynot available

Water capacity40 gal. (151.4 l)

Water capacitynot available

Holding tank capacity - Detail10 gal. (37.9 l)

Holding tank capacity - Detailnot available

Holding tank capacity - Liters37.85

Holding tank capacity - Litersnot available

Holding tank capacity - Gal1

Holding tank capacity - Galnot available

Boat typenot available

Boat typePower

Donzi 45 ZX 2005 vs Donzi Z-21 1987 — Common Questions

Which is the larger boat — the Donzi 45 ZX 2005 or the Donzi Z-21 1987?

The Donzi 45 ZX 2005 is the longer of the two at 45,0 feet overall. The Donzi Z-21 1987 comes in at 21,0 feet, making it roughly 24,0 ft shorter — a meaningful difference in deck room and overall on-water presence.

Which boat can handle a bigger outboard?

The Donzi 45 ZX 2005 is rated to a maximum of 2 550 hp, giving it the larger power ceiling. The Donzi Z-21 1987 tops out at 350 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.

How many people can each boat hold?

The Donzi 45 ZX 2005 is Coast Guard rated for 13 passengers, while the Donzi Z-21 1987 is certified for 6. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.

Which boat has the larger fuel tank — the Donzi 45 ZX 2005 or the Donzi Z-21 1987?

The Donzi 45 ZX 2005 has the bigger tank at 405 gallons, versus 66 gallons on the Donzi Z-21 1987. That 339-gallon difference translates to roughly 1017–1695 nautical miles of additional range at cruising speed, depending on motor, load, and conditions.

Are the Donzi 45 ZX 2005 and Donzi Z-21 1987 from the same manufacturer?

Yes — both the Donzi 45 ZX 2005 and the Donzi Z-21 1987 are built by Donzi. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.

← Donzi 45 ZX 2005 full specs ← Donzi Z-21 1987 full specs