Nissan Laurel 2000GX and 2000SGX Hardtops (1972)
Publication: Car Graphic
Format: Road Impressions
Date: July 1972
Author: “C/G Test Group” (uncredited)
Road testing the Nissan Laurel 2000GX and 2000SGX Hardtops
The Nissan Laurel, which pioneered the intermediate car class in Japan, underwent its first full model change on April 4th, closely following its rival, the Corona Mark II. As a result, the Laurel now has a larger, newly designed body that is closer in size to the Cedric. In addition to the previous G18/G20 four-cylinder engines, the series now also includes the L20 six-cylinder engine found in the Cedric/Gloria, Skyline GT, and Fairlady Z. The body is available in four-door sedan and two-door hardtop configurations. The hardtops retain the previous four-wheel independent suspension with MacPherson struts and coil springs in the front and semi-trailing arms and coil springs in the rear, while the sedans changed the rear suspension to a rigid leaf spring type (a step backward?).
Our test models were the sportiest versions of the four-cylinder and six-cylinder hardtops, the 2000GX (four-cylinder) and 2000SGX (six-cylinder), as well as the top-of-the-line sedan, the 2000SGL (published separately).
The 2000GX’s G20 twin-carb engine is an improved version of the SOHC four-cylinder 1.5-liter engine originally developed by Prince for the Skyline. With a displacement of 1990cc (89x80mm), it has a compression ratio of 8.3 (9.7 for high-octane models) and two Hitachi SU carburetors, producing an output of 120ps/5800rpm and17.0kgm/3600rpm (125ps and 17.5kgm in the high-octane gasoline version). The test car was a regular-octane 120ps model with the standard 4-speed fully-synchronized floor-shift gearbox (a 5-speed gearbox is optional for an extra 20,000 yen, and an automatic is a 55,000 yen option). The price (for delivery in Tokyo) was 895,000 yen, and the car’s color scheme was white with a dark camel-colored interior.
As for the 2000SGX, its L20 twin-carb six-cylinder SOHC engine is in the same state of tune as in the Skyline 2000GT-X, with a displacement of 1998cc (78x70mm), a compression ratio of 8.6, and two Hitachi SU carburetors, producing 125ps/6000rpm and 17.0kgm/4400rpm (the high-octane gasoline version has a compression ratio of 9.5,130ps, and 17.5kgm). The test car was a regular-octane 125ps model with the optional 5-speed fully-synchronized floor-shift gearbox, and was also equipped with an air conditioner (an option that costs an additional 140,000 yen). The standard price of the 4-speed model is 1,030,000 yen, so the test car cost a whopping 1,190,000 yen (!). The color scheme was metallic green, both inside and out.
Before setting off, we compared the interior and exterior of both cars. Both are fitted with high-grade cross-ply tires, Bridgestone Super Speed 2s, but those on the GX have black sidewalls while the SGX’s have double white ribbons. The wheel arches on the SGX are trimmed with chrome plating, and the bullet-shaped mirrors are chrome on the SGX and black on the GX. Looking at the interior, only the GX has a sports-type-design steering wheel with drilled metal spokes, the seats are vinyl on the GX and cloth on the SGX, and only the SGX has power windows. According to the catalog, the maximum speed of both cars is 175km/h (180km/h for the high-octane 5-speed SGX), but judging by appearance and equipment, it seems that the manufacturer has given the four-cylinder GX a sportier character. When we actually got both cars on the road, that is exactly the difference they demonstrated.
Comparing the power-to-weight ratios of the two vehicles, the GX’s is only slightly superior (GX: four-cylinder, 1990cc, 120ps/17.0kgm, 1140kg, 9.50kg/ps; SGX: six-cylinder, 1998cc, 125ps/17.0kgm, 1205kg, 9.64kg/ps). However, once we started driving, we immediately felt that the difference is greater than the numbers suggest. While the GX’s four-cylinder engine felt powerful and sufficiently lively for the car’s size and weight, the SGX’s six-cylinder engine didn’t have as much punch. Throttle response was sluggish, as if the flywheel was unusually heavy. Simply put, it is what we often call a “sleepy" engine. This was later confirmed by acceleration tests at Murayama, where the GX’s 0-400m time was 18.2 seconds, while the SGX took 19.1 seconds (although the SGX was slightly handicapped by the weight of the aforementioned air conditioner).
Part of the reason the SGX was slower was due to the difference in gearboxes. The GX’s 4-speed is light and precise, and the shift lever is shorter than in the previous Laurel, so the stroke is much shorter and shifts are quicker. On the other hand, while the SGX’s 5-speed has powerful synchronization (as does the 4-speed), its action is heavy and the gear engagements feel uncertain, so shifts must be made carefully, losing fractions of a second in the process.
Both of these gearboxes are the same as those used in the Skyline GT, and the 4-speed (3.592 / 2.246 / 1.415 / 1.000) shares the Skyline’s final drive ratio of 3.90, but the 5-speed (3.321 / 2.077 / 1.308 / 1.000 / 0.864) has been shortened to 4.11, so it is not as high-geared as the Skyline. When revved up to 6300rpm, where the red zone begins (it is the same in both cars), the GX reaches 53km/h in first gear, 85km/h in second, and 140km/h in third, while the SGX reaches 55km/h in first, 87km/h in second, 143km/h in third. In other words, the two cars’ gearing is almost identical in the lower gears, so the difference in their acceleration performance can be attributed primarily to the difference in engine power.
Both engines offer excellent flexibility. The GX accelerates reliably from a walking pace in second gear, from 30km/h in third gear, and from 40km/h in fourth gear, albeit with slight driveline vibration (which completely smooths out from just under 50km/h). The SGX, meanwhile, can accelerate in second gear from anything but a complete stop, and accelerates slowly but smoothly from 20km/h in third gear, from 30km/h in fourth gear, and from just 40km/h in overdrive fifth gear.
While both engines are more than flexible enough, the GX clearly offers stronger overall torque, as reflected in the results of the overtaking acceleration tests. Comparing the 40-80km/h and 60-100km/h times in each gear, the GX’s times in third gear were 7.4 and 7.5 seconds, respectively, and 11.5 and 11.0 seconds in fourth. The SGX, meanwhile, required 8.7 and 8.6 seconds in third, 13.1 seconds for both speed ranges in fourth, and 16.2 and 16.6 seconds in fifth. As these figures show, not only is there little difference in acceleration times between the higher and lower speed ranges, the SGX is actually faster in the lower speed range in fifth gear. Still, the absolute times for the GX are significantly quicker. Also, unlike the four-cylinder engine, the six-cylinder suffers from some detonation under hard throttle at low speeds in the higher gears.
Both engines’ output curves really start to pick up from 3000rpm onwards, and for domestically produced 2-liter units, both rev relatively smoothly all the way to their 6300rpm redlines (though both vibrate a bit above 5500rpm). That said, the four-cylinder feels more powerful at higher rpm, while the six-cylinder’s tachometer needle rises more slowly near the top end.
Although the six-cylinder engine falls behind in all aspects of power performance, it is clearly superior in terms of noise. The four-cylinder is powerful, but it also produces a rather gruff, throaty sound (though it is by no means unpleasant). According to the rather optimistic speedometer, 100km/h in the GX (actual speed, 94km/h) corresponds to just under 3300rpm in fourth gear, while in the SGX this corresponds to 3400rpm in fourth gear, and 3000rpm in fifth gear. However, because the six-cylinder engine is inherently quieter, there is no real benefit to shifting up to fifth at this speed in terms of noise, especially as the overdrive gear produces a slight humming sound. Moreover, as mentioned above, the engine’s flexibility eliminates the need for frequent gear changes, so the 5-speed gearbox is probably unnecessary for the six-cylinder; the 4-speed is sufficient. Rather, the 5-speed is probably more valuable when combined with the lively four-cylinder. If the law and circumstances permit, both of these Laurels are able to run comfortably at continuous speeds of 130-140km/h, making them ideal as high-speed cruisers for four people.
As for handling, simply put, this new Laurel not only handles significantly better than the previous model, but also better than its rival, the Corona Mark II, and even its sibling, the sleek Skyline GT. This is due to the synergistic effects of the steering, which has changed from a rack-and-pinion to a recirculating-ball type and has become unexpectedly more rigid and precise, the wider wheelbase and tread (old model, 2620mm and 1315/1310mm; new model, 2670mm and 1350/1330mm), and the suspension, which has been revised and strengthened to the point that almost no parts are shared despite having the same layout as the old model. The handling characteristics are stable, understeer is not too strong, and although the tail eventually begins to slide, the sliding is never sudden and feels safe. This is partly due to the high-speed cross-ply tires, Bridgestone Super Speed 2 6.45S-14s (on 4.5J rims), which do not offer as much grip as radials, but provide a smoother breakaway at the limit.
The large, heavy L20 six-cylinder engine has negative effects on the car’s steering, as well. That is, while steering effort in the four-cylinder GX feels just right, the SGX’s steering feels heavy and unresponsive. However, the strength of the front dampers and the spring constants of the coil springs differ between the six-cylinder and four-cylinder models, with the six-cylinder’s being firmer, so contrary to expectations, the amount of understeer in both cars is almost the same. (The recommended high-speed air pressures were also distributed differently front and rear, 1.9/2.0kg/cm² for the four-cylinder, and 1.9/1.9kg/cm² for the six-cylinder – 2.0/2.0 with the air conditioner.)
In both cars, the ride is excellent regardless of the road surface, and thanks to the four-wheel independent suspension, even rough, unpaved roads can be tackled at high speeds. The stronger dampers and superior seats compared to the previous model also help, but the Bridgestone Super Speed 2 tires are stiff for a cross-ply type, so road noise is rather pronounced.
The brakes are power-assisted discs/drums, equipped with a master cylinder and a proportioning valve to prevent premature rear wheel locking. Braking force, however, is only average, and under full braking from 50km/h with a pedal force of 40-50kg, we measured middling stopping distances of 10.5m for the GX, and 11.7m for the SGX. However, the brakes slow the car effectively from high speeds and are very reliable.
The interior is as luxurious as the Toyota Mark II, offering all the convenience features expected from a domestic car in this class, including effective ventilation. The dashboard design, with panels that slope down and forward, is unique and characteristically Nissan, yet has a pleasing lack of unnecessary ornamentation. The steering column-mounted stalk controls for the wipers (on the left) and lights (on the right) are clearly easier to operate than those on the Mark II (more on the excellent wiper functionality in our report on the sedan).
The driving position, which is lower than that of the previous Laurel, is excellent, and the seat is generously sized and comfortable, with more substantial lumbar support than its appearance suggests. The pedals are well-placed, allowing for natural heel-and-toe driving, and there is sufficient space for the left foot. However, the handbrake is still an umbrella-handle type located under the dash, making it difficult to use, and the return spring for the automatic seatbelt retractor is too strong, making it tempting to immediately unfasten the belt unless persuaded by the warning light, which is dangerous.
Another major drawback is the poor rear visibility. This problem is not limited to the Laurel, and can be said of all recent cars with semi-fastback rooflines, but it is particularly true in this car, where the lower edge of the window is very high and the rear seat headrests protrude significantly, making it extremely difficult to reverse into a garage, as ends of the rear fenders are invisible to the driver.
We have attempted to quantify this with a test. We have a typical driver, about 170cm tall, turn around from the driver’s seat and look back through the rear window. We then measure the point from the rear bumper where the top of a 60cm-high camera ladder begins to appear in the driver’s vision. The results showed that the Laurel has a blind spot that reaches approximately 6m back. In other words, if a child under 60cm tall is within 6m of the rear of the car, the driver will not be able to see them at all, which is extremely dangerous. When we performed the same measurements on the C/G Cherry Van and an editor’s Morris 1100, we could see the ladder in the former car from about 3m away, half the distance of the Laurel, and the latter was even shorter, at just under 2m, so we believe designers who are only concerned with appearances when it comes to styling (although whether this styling is even a plus point is highly questionable) should seriously reflect on this point.
Finally, regarding fuel economy, we drove in a variety of conditions without particular consideration for fuel economy, including crowded city streets (where we spent the majority of our testing time), commuting from the suburbs, and performance testing at Murayama. The results were that the GX with 4-speed gearbox consumed 59.1 liters over 382km, for a total of 6.46km/l, while the SGX with 5-speed consumed 68.4 liters over 356km, for a total of 5.20km/l. These figures show that the six-cylinder engine, even with the 5-speed gearbox, falls short of the four-cylinder engine in terms of fuel economy (both on regular gasoline).
The new Laurel, with its BMW-style European mechanicals wrapped up in an American-style body, is an improvement over the previous Laurel, which had a BMW-like body as well as mechanicals. Aside from the styling, it can be said to have improved in almost every respect, including body rigidity, interior and exterior finish, handling, and ride comfort. However, the heavy, large, and “sleepy” six-cylinder L20 engine clearly compromises the car’s relatively nimble character for its size. Unless one is willing to spend an extra 100,000 yen to “drive slowly,” as the advertisements say, and if one has even the slightest desire to drive a Laurel that is faster and more economical, the four-cylinder is definitely the better choice. Even if you do opt for the six-cylinder, unless you regularly cruise on the highway, the 4-speed gearbox would be a better choice than the heavy-shifting 5-speed.
Postscript: Story Photos
