Volvo 780

Volvo 780: which version to buy (1986–1991 specs compared)

If you are choosing a Volvo 780, you are choosing among six Gasoline versions of one generation (1986–1991), all Sedan 2-doors, all RWD, all with an 80 l tank and 105 mm ground clearance. There is no second generation to “wait for,” and no restyling listed as a separate generation.

If you are choosing a Volvo 780, you are choosing among six Gasoline versions of one generation (1986–1991), all Sedan 2-doors, all RWD, all with an 80 l tank and 105 mm ground clearance. There is no second generation to “wait for,” and no restyling listed as a separate generation. The real split is engine: a 2316 cm³ 4-cylinder Inline Turbo at 160 hp versus two naturally aspirated 6-cylinder Inline 2.9-litre families at 147 hp and 156 hp. Gearbox then splits each engine: Automatic 4 versus Manual (4 speeds on the turbo, 5 on both 2.9 manuals). Kerb weight, 0–100, top speed, mpg, CO2, and wheel size are not measured on every version, so this buyer’s guide ranks what the data actually measures: power, displacement, specific output, cylinders, boost, gearbox, fuel, and which chassis details are filled in.

Volvo 780 generations: what actually changed

1 generation (1986–1991), Sedan 2-doors, 6 versions. Production start and stop are the same on the generation and on every version: 1986-01-01 to 1991-12-31. You cannot pick an “early” versus “late” generation from these years; you pick a powertrain.

What is not different between versions: body (Sedan 2-doors), drive (RWD), tank (80 l), ground clearance (105 mm), front suspension (Independent, spring), front brakes (Ventilated disc), fuel type where listed (Gasoline). Weight (kerb and gross), rear wheels, 0–100, top speed, city/highway/combined consumption, CO2, eco class, and tyre size are not measured for all six, so they cannot break a tie.

What is different, and is the whole buying decision:

Arithmetic on the given numbers: the turbo 2.3 makes 13 hp more than the 147 hp 2.9 (160 − 147) and 4 hp more than the 156 hp 2.9 (160 − 156), from 574 cm³ less displacement than 2890 (2890 − 2316) and 584 cm³ less than 2900 (2900 − 2316). The two 2.9 families differ by 10 cm³ (2900 − 2890) and 9 hp (156 − 147). Specific output of the 2.3 is 18.2 hp/l above the 147 hp 2.9 (69.1 − 50.9) and 15.3 hp/l above the 156 hp 2.9 (69.1 − 53.8).

Volvo 780 engine and gearbox specs (exact version names)

Use these names as listed. Two 2.9 AT and two 2.9 MT exist; they are not the same car — separate them by 147 hp versus 156 hp.

Torque (Nm and rpm) is not measured on all six. Power rpm is not measured on 2.3 AT, 2.3 MT, and both 147 hp 2.9 versions; it is 4200 only on the 156 hp 2.9 AT and 2.9 MT.

Volvo 780 performance, mpg, and reliability-relevant gaps

0–100, top speed, city / highway / mixed consumption, CO2, eco class: not measured on 2.3 AT, 2.3 MT, 2.9 AT (147 hp), 2.9 MT (147 hp), 2.9 AT (156 hp), and 2.9 MT (156 hp). You cannot rank “which is faster to 100” or “which uses less fuel” from this catalogue. Weight is also not measured, so hp per kilogram is not calculable; do not treat 160 hp as automatically quicker than 156 hp or 147 hp on the road until mass is known.

What you can use as a proxy:

• Highest listed output: 2.3 AT and 2.3 MT at 160 hp / 118 kW with Turbo.
• Mid output: 2.9 AT (156 hp) and 2.9 MT (156 hp) at 156 hp / 115 kW, 4 hp below the turbo (160 − 156), 9 hp above the other 2.9 (156 − 147).
• Lowest listed output: 2.9 AT (147 hp) and 2.9 MT (147 hp) at 147 hp / 108 kW.
• Manual extra ratio: 2.3 MT is still 4 speeds; both 2.9 MT versions are 5. That is 1 extra gear on the 2.9 manuals versus 2.3 MT and versus every Automatic (4).
• Fuel grade: 92 is stated for all four 2.9 versions; fuel grade for 2.3 AT and 2.3 MT is not measured.
• Feed: Carburetor is stated only on the 156 hp 2.9 AT and 2.9 MT; the other four versions have feed not measured. That is a specification difference, not a consumption figure.

Problems and reliability are not in the numeric table (no failure rates). The only reliability-adjacent facts you can state without inventing them: Turbo versus No boost, 4 versus 6 cylinders, Carburetor only on the 156 hp 2.9 pair, and Automatic 4 versus Manual 4 or 5.

Volvo 780 dimensions, weight, tank, clearance

2.9 AT (156 hp) and 2.9 MT (156 hp) add rear suspension: Independent, spring (same wording as the front). Rear suspension on 2.3 AT, 2.3 MT, 2.9 AT (147 hp), and 2.9 MT (147 hp) is not measured — that is a gap in the sheet, not proof those cars have no rear suspension.

Rear brakes: Disc on all four 2.9 versions; not measured on 2.3 AT and 2.3 MT. Front brakes are Ventilated disc on all six.

Engine placement: Front, longitudinal on 2.3 AT and 2.3 MT; not measured on all 2.9 versions.

There is no dimension set (length, width, height, wheelbase) in the data, so you cannot compare cabin size or boot between versions.

Which Volvo 780 version to choose

If you want the highest listed power and the highest power per litre: 2.3 AT or 2.3 MT. Both are 160 hp / 118 kW from 2316 cm³, 4 Inline, Turbo, RWD. Specific output is 69.1 hp/l. Versus 2.9 AT (147 hp) that is +13 hp and +18.2 hp/l from 574 cm³ less capacity. Versus 2.9 AT (156 hp) that is +4 hp and +15.3 hp/l from 584 cm³ less. You do not get a 0–100 or mpg number to cash that in. You also do not get rear brake or rear suspension filled in, unlike the 2.9 rows.

Automatic vs manual on the turbo: 2.3 AT and 2.3 MT share every measured engine number. The only listed difference is gearbox: Automatic 4 versus Manual 4. There is no fifth gear on 2.3 MT. If you want a manual and 5 speeds, the turbo pair does not offer it; that combination exists only as 2.9 MT (147 hp) and 2.9 MT (156 hp).

If you want six cylinders and 92 fuel stated, at the lower power: 2.9 AT (147 hp) or 2.9 MT (147 hp). 2890 cm³, 6 Inline, boost No, 147 hp / 108 kW, fuel 92, rear brakes Disc. You give up 13 hp versus the 2.3 pair and 9 hp versus the 156 hp 2.9 pair. You gain 574 cm³ over the 2.3 and 1 extra manual gear if you take 2.9 MT (147 hp) instead of 2.3 MT. Feed, engine position, power rpm, and rear suspension remain not measured.

If you want the stronger of the two 2.9 families, and the most complete chassis line on the sheet: 2.9 AT (156 hp) or 2.9 MT (156 hp). 2900 cm³, 6 Inline, boost No, 156 hp / 115 kW at 4200 rpm, Carburetor, fuel 92, rear suspension Independent, spring, rear brakes Disc. Versus the 147 hp 2.9: +9 hp, +10 cm³, +2.9 hp/l (53.8 − 50.9), plus listed rpm, carburetor, and rear spring independent suspension. Versus the 2.3 turbo: −4 hp, −15.3 hp/l, +584 cm³, 6 cylinders instead of 4, no turbo. 2.9 AT (156 hp) is Automatic 4; 2.9 MT (156 hp) is Manual 5.

What “extra” does not buy here: there is no price in the data, so “extra money” cannot be a currency figure. The extra specification of the 156 hp 2.9 versus the 147 hp 2.9 is 9 hp, 10 cm³, a stated 4200 rpm, Carburetor, and rear Independent, spring. The extra of the 2.3 versus either 2.9 is Turbo, 4 cylinders, 2316 cm³, 160 hp, Front, longitudinal, and (on the manual) only 4 gears. Tank (80 l) and clearance (105 mm) do not change with any of those choices.

Short pick list

1. Peak listed hp and specific output: 2.3 AT (auto) or 2.3 MT (manual 4). 2. Six cylinders, 5-speed manual, lower 2.9 output: 2.9 MT (147 hp). 3. Six cylinders, auto, lower 2.9 output: 2.9 AT (147 hp). 4. Six cylinders, Carburetor, 156 hp, rear suspension listed, auto: 2.9 AT (156 hp). 5. Same engine as (4) with Manual 5: 2.9 MT (156 hp).

Do not choose by generation: there is only 1 generation. Do not choose by tank, clearance, body, or drive: they are identical. Do not choose by 0–100, mpg, or weight: those values are not measured. Choose by 160 / 156 / 147 hp, Turbo versus No, 4 versus 6 cylinders, 2316 / 2890 / 2900 cm³, and Automatic 4 versus Manual 4 or 5, using the version names 2.3 AT, 2.3 MT, 2.9 AT, and 2.9 MT exactly as above.