Cadillac DeVille

Which generation changed what (buyer’s cut)

Use the catalogue names as printed. Same 4.6 AT (or 7.0 AT, 7.7 AT, 6.4 AT, 4.5 AT) must be split by horsepower.

1 generation (1958–1960), Coupe Hardtop, 2 versions: both 6.4 AT, RWD, Automatic. The 330 hp car is the only early DeVille with a full measured set: 583 Nm at 3100 rpm, 2220 kg kerb, 11.2 s to 100 km/h, 197 km/h, 4 gears, compression 10.5. The 325 hp twin leaves 0–100, top speed, torque, and kerb not measured.

2 generation (1961–1964), Coupe, 2 versions: 6.4 AT 325 hp with 4 gears versus 7.0 AT 340 hp with 3 gears. The extra 600 cc and 15 hp cost one ratio. 0–100, top speed, torque, kerb, tank, wheels: not measured on both.

3 generation (1965–1970), Cabrio, 2 versions: the only open DeVille. 7.0 AT 340 hp versus 7.7 AT 375 hp — +35 hp and +730 cc. Both RWD, Automatic, 3 gears. Performance, weight, tank, clearance, fuel grade: not measured.

4 generation (1971–1976), Coupe, 2 versions, both named 7.7 AT and both 375 hp / 495 Nm / 7730 cc. Distinguish them by measurement: one has 0–100 8.6 s and top speed 206 km/h; the other has those not measured. This is the horsepower ceiling of the whole model.

5 generation (1977–1984), Coupe, 5 versions: last RWD chapter, Automatic 3 gears, engine Front, longitudinal. Power collapses relative to the 7.7 AT: peak here is 7.0 AT 195 hp. The 6.0 AT 140 hp is the only DeVille with a full mpg set besides the late 4.6 AT cars, and it is the slowest measured sprint (15.2 s).

6 generation (1985–1993), Coupe, 5 versions: drive flips to FWD. Peak 4.9 AT 200 hp. Unique 4.3 AT Diesel, 85 hp, 6 cylinders, V-shaped. Two 4.5 AT entries are both 155 hp — tell them apart by rear suspension: one Independent, spring, one not measured.

7 generation (1994–1999), Sedan, 4 versions: 4.6 AT in 270 / 275 / 300 hp plus leftover 4.9 AT 200 hp. Rear brakes split the family: Drum on 270 hp, 275 hp, and 4.9 AT; Disc on 300 hp. Tank 76 L, clearance 147 mm.

8 generation (1999–2005), Sedan, 3 versions, all 4.6 AT (275 / 290 / 300 hp), FWD, Automatic 4, engine Front, transverse, No boost. Tank shrinks to 70 L (−6 L versus 7 generation). Clearance 134 mm (−13 mm). Rear brakes Disc on all three. This is the only generation where city / highway / mixed consumption is measured on every version, and the figures are identical.

Engine and specs: same badge, different output

Use the catalogue names as printed. Same 4.6 AT (or 7.0 AT, 7.7 AT, 6.4 AT, 4.5 AT) must be split by horsepower.

Specific power (hp per litre of the stated displacement):

• 8 generation 4.6 AT 300 hp: 300 / 4.568 ≈ 65.7 hp/L (highest in the file).
• 8 generation 4.6 AT 290 hp: 290 / 4.568 ≈ 63.5 hp/L.
• 8 generation 4.6 AT 275 hp: 275 / 4.565 ≈ 60.2 hp/L.
• 7 generation 4.6 AT 270 hp: 270 / 4.565 ≈ 59.1 hp/L.
• 7 generation 4.9 AT 200 hp: 200 / 4.892 ≈ 40.9 hp/L.
• 6 generation 4.3 AT 85 hp: 85 / 4.300 ≈ 19.8 hp/L (lowest).
• 6 generation 4.1 AT 135 hp: 135 / 4.100 ≈ 32.9 hp/L.
• 6 generation 4.5 AT 155 hp: 155 / 4.467 ≈ 34.7 hp/L.
• 5 generation 5.8 AT 120 hp: 120 / 5.737 ≈ 20.9 hp/L.
• 5 generation 7.0 AT 195 hp: 195 / 6.960 ≈ 28.0 hp/L.
• 4 generation 7.7 AT 375 hp: 375 / 7.730 ≈ 48.5 hp/L.
• 1 generation 6.4 AT 330 hp: 330 / 6.384 ≈ 51.7 hp/L.

The late 4.6 AT makes more horsepower from 4565–4568 cc than the 7.7 AT does per litre from 7730 cc. Buying displacement is not buying output.

Inside 8 generation, the 4.6 AT 290 hp is the odd one: +15 hp versus 275 hp, but torque drops from 407 Nm at 4000 rpm to 386 Nm at 4400 rpm (−21 Nm). The 300 hp car recovers to 400 Nm at 4400 rpm — still 7 Nm below the 275 hp peak, produced 400 rpm higher.

Valve count is a filter: 4 valves per cylinder on every 4.6 AT and on 6 generation 4.1 AT; 2 valves on 4.9 AT, both 4.5 AT, and the 5 generation petrol V-shaped 8. Valves on 4.3 AT, both 7.7 AT in 4 generation, 3 generation, and 2 generation: not measured.

Injection versus carburetor only splits 5 generation 7.0 AT: 195 hp is Distributed injection (multi-point); 180 hp is Carburetor. Same 6960 cc, same 434 Nm, same 8.2 compression. The injected car adds 15 hp and raises peak-power rpm from 4000 to 4400. 1 generation 6.4 AT 330 hp is also Carburetor.

Fuel grade is a running-cost proxy where it is measured: 98 only on 6 generation 4.1 AT; 95 on 7 generation 4.6 AT 270 hp and 4.9 AT; 92 on all 8 generation 4.6 AT and on 7 generation 4.6 AT 275 hp and 300 hp; 80 on every 5 generation petrol version. 4.3 AT is Diesel. Early 7.7 AT / 7.0 AT / 6.4 AT: fuel grade not measured.

Performance and economy (mpg where it exists)

Measured 0–100 km/h, fastest to slowest:

• 8 generation 4.6 AT 290 hp: 7.3 s, 210 km/h.
• 8 generation 4.6 AT 300 hp: 7.3 s, 210 km/h (same sprint and top speed as 290 hp).
• 7 generation 4.6 AT 300 hp: 7.5 s, 210 km/h (+0.2 s versus the later 300 hp).
• 8 generation 4.6 AT 275 hp: 7.6 s, 180 km/h (+0.3 s, −30 km/h versus the 300 hp in the same generation).
• 4 generation 7.7 AT (measured twin): 8.6 s, 206 km/h — 1.3 s slower than the late 300 hp despite +75 hp.
• 1 generation 6.4 AT 330 hp: 11.2 s, 197 km/h.
• 5 generation 4.1 AT 144 hp: 14.2 s, 168 km/h.
• 5 generation 6.0 AT 140 hp: 15.2 s, 168 km/h (slowest measured).

All other versions: 0–100 not measured, top speed not measured. That includes 7 generation 4.6 AT 270 hp and 275 hp, 7 generation 4.9 AT, every 6 generation car, 5 generation 7.0 AT and 5.8 AT, 3 generation both versions, 2 generation both versions, and 1 generation 6.4 AT 325 hp.

Consumption is measured on four cars only.

All three 8 generation 4.6 AT versions share 13.1 city / 8.7 highway / 10.7 mixed L/100 km. The 25 hp from 275 to 300 does not change the listed mpg. CO2 and eco class: not measured.

5 generation 6.0 AT 140 hp: 15.7 city / 10.2 highway / 13.8 mixed — +2.6 / +1.5 / +3.1 versus the late 4.6 AT. It is the only RWD DeVille with mpg in the file.

Every other version: city, highway, mixed not measured. There is no mpg line for the Diesel 4.3 AT, so it cannot be sold as the economy pick on this dataset.

Dimensions, weight, tank, wheels

Wheel size: not measured on every version.

Ground clearance, where measured: 147 mm (7 generation, all four); 145 mm (6 generation, all five); 140 mm (5 generation, all five); 134 mm (8 generation, all three). 4–1 generation: not measured. The late sedan sits 13 mm lower than the 7 generation sedan.

Tank: 76 L on all 7 generation versions; 70 L on all 8 generation versions. 6 generation and earlier: not measured. Mixed 10.7 L/100 km on 70 L is a larger measured range than 13.8 L/100 km on an unlisted tank for 6.0 AT.

Kerb weight, lightest measured to heaviest:

• 7 generation 4.9 AT 200 hp: 1703 kg.
• 7 generation 4.6 AT 270 hp and 275 hp: 1809 kg (+106 kg versus 4.9 AT).
• 7 generation 4.6 AT 300 hp and 8 generation 4.6 AT 275 hp: 1845 kg.
• 8 generation 4.6 AT 290 hp and 300 hp: 1880 kg.
• 5 generation 6.0 AT: 1905 kg.
• 1 generation 6.4 AT 330 hp: 2220 kg (heaviest measured).

Gross weight only on 8 generation: 2500 kg (275 hp) and 2550 kg (290 hp and 300 hp). All other generations: gross not measured. Payload on the 275 hp late car: 2500 − 1845 = 655 kg; on the 300 hp: 2550 − 1880 = 670 kg.

kg per hp (kerb / hp), where both exist:

• 7 generation 4.6 AT 300 hp: 1845 / 300 = 6.15 kg/hp (best measured).
• 8 generation 4.6 AT 300 hp: 1880 / 300 = 6.27 kg/hp.
• 8 generation 4.6 AT 290 hp: 1880 / 290 = 6.48 kg/hp.
• 7 generation 4.6 AT 270 hp or 275 hp: 1809 / 270 = 6.70; 1809 / 275 = 6.58.
• 8 generation 4.6 AT 275 hp: 1845 / 275 = 6.71 kg/hp.
• 1 generation 6.4 AT 330 hp: 2220 / 330 = 6.73 kg/hp.
• 7 generation 4.9 AT: 1703 / 200 = 8.52 kg/hp.
• 5 generation 6.0 AT: 1905 / 140 = 13.61 kg/hp (worst among weighed cars).

Length, width, and size in metres or feet: not measured in this file. Searches for DeVille length cannot be answered from these specs.

Which version to choose

Daily late sedan, fastest measured pair: 8 generation 4.6 AT 300 hp or 4.6 AT 290 hp. Both 7.3 s and 210 km/h, both 1880 kg, both 13.1 / 8.7 / 10.7, both 70 L, both 134 mm, both FWD, Automatic 4, Front, transverse, 4 valves, No boost, fuel 92. The 300 hp car adds 10 hp and 14 Nm over 290 hp with no change in the sprint or top-speed lines. If those two numbers are the test, 290 hp is redundant.

Same generation, lower kerb, more torque: 8 generation 4.6 AT 275 hp. You give up 25 hp and 30 km/h of top speed and 0.3 s on 0–100, and you gain 21 Nm (407 vs 386 on the 290) plus 35 kg less kerb than the 300. Mixed mpg is the same 10.7. Gross is 50 kg lower (2500 vs 2550).

Same 300 hp, more clearance and tank: 7 generation 4.6 AT 300 hp. Versus 8 generation 4.6 AT 300 hp: same 300 hp and 400 Nm at 4400 rpm, same 4568 cc, same 210 km/h; 0–100 7.5 s instead of 7.3 s; kerb 1845 kg instead of 1880 kg (−35 kg, 6.15 vs 6.27 kg/hp); tank 76 L vs 70 L; clearance 147 mm vs 134 mm; rear Disc in both 300 hp sedans. City/highway/mixed on the 7 generation 300: not measured. Engine placement on 7 generation: not measured (on 8 generation it is Front, transverse).

Avoid mixing the two 275 hp sedans: 7 generation 4.6 AT 275 hp and 8 generation 4.6 AT 275 hp share the name and 275 hp / 202 kW / 407 Nm / 4565 cc. The later car has measured 7.6 s / 180 km/h / 13.1 / 8.7 / 10.7, kerb 1845 kg, tank 70 L, clearance 134 mm, rear Disc. The 7 generation 275 has 0–100, top speed, and mpg not measured, kerb 1809 kg, tank 76 L, clearance 147 mm, rear Drum. Buying “a 275 4.6 AT” without the generation is buying two different brake and tank packages.

Lightest kerb in the sedan years: 7 generation 4.9 AT 200 hp, 1703 kg. Versus the 300 hp 4.6 AT in the same generation that is +100 hp, +142 kg, 2 valves vs 4, 373 Nm vs 400 Nm, fuel 95 vs 92, rear Drum vs Disc. Specific power 40.9 vs 65.7 hp/L. 0–100 not measured. Take it only if mass matters more than the measured 7.5 s of the 300.

Last RWD with a mpg line: 5 generation 6.0 AT 140 hp, 1905 kg, 15.2 s, 168 km/h, 15.7 / 10.2 / 13.8, rear Drum, Independent, spring both ends, 3 gears, fuel 80. Versus 8 generation 4.6 AT 300 hp: −160 hp, +7.9 s, −42 km/h, +3.1 mixed L/100 km, +25 kg. The extra displacement (6036 vs 4568 cc) buys less of every measured performance number.

Most horsepower in the file: either 4 generation 7.7 AT 375 hp (the one with 8.6 s / 206 km/h, or the twin with those not measured). Versus 8 generation 4.6 AT 300 hp: +75 hp, +95 Nm, +3162 cc, RWD vs FWD, 3 gears vs 4, 0–100 +1.3 s where measured, top speed −4 km/h. Peak power here is not the fastest sprint.

Only Cabrio: 3 generation 7.7 AT 375 hp over 7.0 AT 340 hp if you want the extra 35 hp and the 495 Nm that the 340 does not list (torque on 7.0 AT: not measured). No 0–100, weight, or tank on either.

Only Diesel: 6 generation 4.3 AT 85 hp, 6 cylinders, V-shaped, 224 Nm, FWD, Automatic 4, boost No. Supply system, compression, bore × stroke, 0–100, top speed, mpg, tank, kerb, valves: not measured. Versus the weakest petrol in that Coupe, 4.1 AT 135 hp, the diesel is −50 hp and −95 Nm.

Do not buy on engine size alone: 5 generation 5.8 AT 120 hp from 5737 cc (20.9 hp/L) is 24 hp below the 4.1 AT 144 hp from 4100 cc in the same generation, and 180 hp below the later 4.6 AT 300 hp. 5.8 AT 0–100: not measured.

Early Coupe Hardtop with a complete card: 1 generation 6.4 AT 330 hp — 583 Nm is the highest torque in the file, 2220 kg the highest kerb, 11.2 s / 197 km/h, 4 gears, 10.5 compression, Carburetor, rear Dependent, leaf spring, rear Drum. The 325 hp 6.4 AT in the same generation does not add a second measured performance point.

Problems / reliability: not measured in this dataset. The arithmetic that is measured is power density, mass per hp, clearance, tank, brakes, and the few 0–100 and mpg lines above. Use those, and keep the version strings 4.6 AT, 4.9 AT, 4.5 AT, 4.3 AT, 4.1 AT, 7.0 AT, 5.8 AT, 6.0 AT, 7.7 AT, 6.4 AT exactly as listed.