Reference

Specifications

Almost every E-Type specification table on the internet has the same three faults. It quotes 265bhp without saying that is a gross figure. It mixes dry weights with kerb weights, which differ by around 380lb on the same car. And it gives one set of figures for a car that was sold in two market specifications. This page names the standard behind every number, shows where good sources disagree, and says plainly when something has not been established.

Figures are given in both metric and imperial, and in both imperial and United States gallons where capacities are concerned, because the readership is on both sides of the Atlantic and the two gallons are not the same thing.

How to read the power figures, because this is where most tables go wrong

Three different measurement standards appear in E-Type literature and they are not interchangeable.

SAE gross. The output of a bare engine on a test stand, with no engine driven accessories, free flowing exhaust and optimal ignition timing. This is what the famous 265bhp is.
SAE net. A closer approximation of the engine as actually installed in the car.
DIN. A net methodology, but with different test parameters again.

There is no reliable conversion between them. The difference between gross and net can be as little as 5 per cent or more than 25 per cent depending on the engine, so a net figure cannot be derived from a gross one. Where this archive has not found a figure stated to a particular standard, it says so rather than guessing.

Engine

Engine specifications by variant and market. Scroll sideways on a narrow screen.
Variant	Capacity	Bore and stroke	Compression	Carburation	Power	Torque
3.8 XK six, home market	3,781cc	87mm by 106mm	9.0 to 1, 8.0 to 1 optional	Three SU HD8	265bhp SAE gross at 5,500rpm	260lb ft at 4,000rpm
4.2 XK six, home market	4,235cc	92.07mm by 106mm	9.0 to 1, 8.0 to 1 optional	Three SU HD8	265bhp SAE gross at 5,400rpm	283lb ft at 4,000rpm
4.2 XK six, United States from 1968	4,235cc	92.07mm by 106mm	As home market	Two Zenith Stromberg	246bhp SAE gross	Not established
5.3 V12, home market	5,343cc	90mm by 70mm	9.0 to 1	Four Zenith Stromberg	272bhp DIN at 5,850rpm, or 314bhp gross at 6,200rpm	304lb ft DIN at 3,600rpm, or 349lb ft gross at 3,800rpm
5.3 V12, United States from 1973	5,343cc	90mm by 70mm	7.8 to 1	Four Zenith Stromberg	241bhp at 5,750rpm or 244bhp at 5,250rpm, standard unstated in both sources	285lb ft at 3,500rpm

The 265 and the 246, settled as far as the sources allow

Both are SAE gross figures. That matters, because it means the drop from 265 to 246 on American cars is a genuine like for like comparison of two engines, not an artefact of two different measuring standards. A common error online is to present 246 as the net figure for the same engine. It is not.

Two further points. 265bhp applies to both the 3.8 and the 4.2, at 5,500 and 5,400rpm respectively. The 4.2's gain was torque, from 260 to 283lb ft, not peak power, so any table showing the 4.2 as more powerful than the 3.8 is wrong. And the net figure for the American 4.2 is quoted in one place as 171bhp, which the archive records as single sourced and uncorroborated.

The DIN or net figure for the home market 3.8 and 4.2 has not been established at all.

Dimensions

Note that the 2+2 and every Series 3 sit on the long wheelbase.

Dimensions by model. Scroll sideways on a narrow screen.
Model	Wheelbase	Length	Width	Front track	Rear track
Series 1, 1.5 and 2, two seater	96in, 2,438mm	175.3in, 4,453mm	65.3in, 1,657mm	50.0in, 1,270mm	50.0in, 1,270mm
Series 1, 1.5 and 2, 2+2	105in, 2,667mm	184.5in, 4,686mm	65.3in, 1,657mm	50.0in, 1,270mm	50.0in, 1,270mm
Series 3, all bodies	105in, 2,667mm	184.4in, 4,684mm	66.1in, 1,679mm	54.4in, 1,381mm	53.4in, 1,356mm

Heights differ by body style and are frequently reported as a single figure per series, which silently drops one. The coupe is 48.1in and the roadster 46.5in on the six cylinder cars.

Three figures that are routinely misquoted

The 66.1 inch figure is the Series 3 roadster's overall width, not its track. Its track is 54.4 inches at the front and 53.4 at the rear. The confusion propagates because specification panels often list width and omit track, which invites a later writer to relabel it.

The Series 3 track increase is unusually well corroborated. One specialist gives 54.375in and 53.375in, and a contributor citing Jaguar's own Series 3 press releases gives the increase over Series 1 as four and three eighths of an inch at the front and three and three eighths at the rear. Applied to the Series 1's 50 inches, those agree exactly.

A length of 4,375mm circulates for the Series 1 3.8. It has no corroboration against 4,453mm from two other sources and appears to be an error. The archive records it as a disagreement and does not adopt it.

Weights, and why every table disagrees

There are three distinct families of E-Type weight figure in circulation. Mixing them is the commonest fault in E-Type tables, and it is why you will see the same car quoted at 2,520lb in one place and 2,900lb in another. Both are correct. They are measuring different things.

The three weight bases. Scroll sideways on a narrow screen.
Basis	What it includes	Example	Source
Maker's dry weight	The car without fluids, fuel, spare wheel or tools	4.2 fixed head coupe, 2,520lb, 1,143kg	Motor Sport, January 1965, the only located source that explicitly labels a weight as the maker's dry weight
Manufacturer's unladen weight	Factory derived service data, basis not further defined	Two seater 2,426lb, coupe 2,481lb, 2+2 2,778lb	Specialist service data
Kerb weight	The car ready to drive	Series 1 roadster 2,770lb, coupe 2,900lb, 2+2 3,090lb	Multiple modern references

The gap between the maker's dry weight for a fixed head coupe, 2,520lb, and the kerb weight for a fixed head coupe, 2,900lb, is 380lb, or about 15 per cent. That is fluids, fuel, the spare wheel and the tools. It is not an error in either figure.

A caution on the archive's own comparison: the 2,520lb figure is a 4.2 coupe and the 2,900lb figure is a Series 1 coupe of unspecified engine, so it is not a perfectly matched pair. A properly matched dry against kerb comparison for one identified car has not been established.

Series 3 weights are quoted as 3,361lb for the coupe and 3,380lb for the roadster by most references, and as 3,500lb by one specialist, a gap of over a hundred pounds that no source reconciles.

Performance, measured against claimed

This is the section where the difference between a claim and a measurement matters most, and where the E-Type's best known number turns out to need a great deal of qualification.

Period road test figures as published. Scroll sideways on a narrow screen.
Publication	Date	Car	Axle	Maximum	0 to 60	Notes
Autocar	24 March 1961	9600 HP, 3.8 fixed head coupe	Not established	150.4mph mean, 151.7mph best	6.9 sec	See below on this car's preparation
The Motor	22 March 1961	77 RW, 3.8 roadster	Not established	149.1mph	7.1 sec	Standing quarter 15.1 sec, 21.3mpg imperial
The Motor	October 1964	4.2 fixed head coupe	Not established	150mph	7.0 sec	Standing quarter 14.9 sec
Autocar	May 1965	4.2 fixed head coupe	Not established	153mph	7.6 sec	The highest independently attributed maximum for any road going E-Type the archive has found, and three above the factory claim. Single sourced
Motor Sport	January 1967	4.2 2+2, manual	3.07 to 1	140mph	Not given	Standing quarter under 15.5 sec, 18.2mpg overall
Motor Sport	April 1967	4.2 coupe, left hand drive, 8 to 1 pistons	3.07 to 1	143mph	Not given	A long term car at about 44,000 miles
Motor Sport	January 1972	Series 3 2+2, manual	3.07 to 1	143mph, gearing derived	Not given	Standing quarter 14.5 sec, 0 to 100 in 16.5 sec, 16.4mpg

The 150mph question

Jaguar claimed 150mph at the Geneva launch in March 1961, and two road tests published within days of each other appeared to confirm it. What is documented about those two cars complicates the picture considerably.

Both press cars ran Dunlop R5 racing tyres, which have a larger rolling diameter and lower drag than road tyres and therefore raise top speed for a given gearing.

9600 HP, the coupe Autocar tested at a mean 150.4mph, was found on later examination to have a gas flowed cylinder head carefully matched to its manifolds, described by one account as possibly worth an extra 20 to 25 brake horsepower. That is an estimate, not a measurement.

Autocar itself now concedes the point. Its own modern retrospective says the car was most likely specially prepared for those tests. That is the strongest single statement available: the magazine that published the figure says its car was probably not standard.

The archive should be careful about what this does not establish. The Heritage Trust's own page on 77 RW, the roadster The Motor tested at 149.1mph, makes no mention of special preparation, and the gas flowed head is attributed only to 9600 HP. The allegation should not be extended to the second car.

A third car is frequently confused with these two. 6162 RW carried an aluminium sump and a 3.07 axle, and with it Paul Frere achieved 159mph at Monza, with Motoring News reporting over 160. Those figures belong to that car and not to the 1961 road tests.

And Motor Sport's Bill Boddy calculated a pretty genuine 155mph on the M1 at 6,100rpm. That is an rpm and gearing calculation, not a timed two way mean, and it should never be tabulated alongside measured figures.

What can be said fairly is that a standard 3.8 did not generally reach 150mph, that most cars failed to reach it, and that around 135mph is the figure quoted for a standard car.

Capacities, and the gallon problem

An imperial gallon is about 4.55 litres and a United States gallon about 3.79. They differ by roughly 20 per cent, which is large enough to matter when you are filling a sump. Several widely used specification tables give capacities in United States units without saying so, which is how a fuel tank quoted as 14 gallons in one place appears as 16.75 in another. Both can be right.

Where this archive gives a capacity it names the unit. Where a source does not name its unit, the archive says so rather than assuming.

United States specification, where the numbers differ

Carburation. Through the whole of the Series 1 proper there is no difference: every Series 1 had three SU HD8 carburettors. From the 1968 model year American cars have two Zenith Strombergs.
Power. 265bhp gross falls to 246bhp gross on the American 4.2. On the V12, home market cars are 272bhp DIN while American cars from 1973 are quoted at 241 or 244bhp with the standard unstated in both cases.
Compression. The V12 drops from 9.0 to 1 to 7.8 to 1 for the American market from 1973.
Model year conventions. American cars are described by model year and British cars by build date. A car built in late 1967 may be a 1968 model in America, which causes constant confusion when comparing specification tables across the Atlantic.

One period comparison is worth recording because it is the closest thing to a like for like test the archive has found. Motor Sport ran a left hand drive export specification 4.2 coupe on low compression 8 to 1 pistons as a long term car, and reached 143mph on a 3.07 axle. Two years earlier the same magazine had quoted 150mph for a home market 9 to 1 car on the same axle. That is a 7mph difference between export and home specification, from one publication using consistent methods.

What the archive has not established

Any DIN or net power figure for the home market 3.8 or 4.2.
The axle ratio of either 1961 press car, which matters because Autocar's own published data said 150 plus miles per hour according to axle ratio.
Whether 77 RW was specially prepared, as distinct from 9600 HP, which was.
A properly matched dry against kerb weight comparison for one identified car.
Any period Series 2 road test with performance figures. None was located.
Why one specialist's Series 3 kerb weight is over a hundred pounds above every other source.

Common questions

How much power does a Jaguar E-Type have?

265bhp for both the 3.8 and the 4.2, but that is an SAE gross figure, measured on a bare engine with no accessories and a free flowing exhaust, so it is not what the engine made in the car. American cars from 1968 are 246bhp on the same gross basis. The V12 is 272bhp DIN or 314bhp gross, which are the same engine measured two ways.

Is the 4.2 more powerful than the 3.8?

No. Both are quoted at 265bhp gross, at 5,500rpm for the 3.8 and 5,400rpm for the 4.2. The 4.2's gain was torque, from 260 to 283lb ft. Any table showing the 4.2 with more peak power than the 3.8 has an error in it.

How much does a Jaguar E-Type weigh?

It depends entirely on which weight you mean. A fixed head coupe is 2,520lb as a maker's dry weight and 2,900lb as a kerb weight. That 380lb difference is fluids, fuel, the spare and the tools. Both figures are correct and tables that mix the two are the reason published E-Type weights never agree.

Did the E-Type really do 150mph?

The two 1961 road tests recorded 150.4mph and 149.1mph, but both cars ran racing tyres, and the coupe was later found to have a gas flowed cylinder head. Autocar's own modern retrospective says its test car was most likely specially prepared. A standard 3.8 is generally quoted at around 135mph.

What is the difference between a British and an American specification E-Type?

Through the Series 1 the mechanical specification is the same, including the three SU carburettors. From the 1968 model year American cars have two Zenith Strombergs and lower quoted power, 246bhp gross against 265. On the V12, American cars from 1973 run 7.8 to 1 compression against 9.0 elsewhere.

Sources

Motor Sport archive, road tests and long term reports of January 1965, January 1967, April 1967 and January 1972, and the reader correspondence of May 1961 quoting Autocar's published data.
Autocar, 24 March 1961 road test of 9600 HP, and Autocar's own modern retrospective on that car's preparation.
The Motor, 22 March 1961 road test of 77 RW, and the October 1964 test of the 4.2.
Jaguar Daimler Heritage Trust pages on the E-Type and on 77 RW.
Specialist service data for unladen weights, capacities and tyre pressures.
Classic and Sports Car, on the test car's preparation.
Wikipedia's XK engine article, one of only two located sources naming the 265bhp figure as SAE gross.
A note on corroboration: several sites reproducing E-Type specifications are reproducing Wikipedia verbatim, so apparent agreement between three sources is sometimes one source counted three times.

Last reviewed 10 September 2026.