Vintage CL Review: 1970 AMC Javelin SST 390 – “A Little More Trans-Am, And A Little Less Rambler”

When it debuted for 1968, the AMC Javelin was a promising also-ran in the hotly contested pony car segment. However, American Motors hadn’t sat still, whittling away at the Javelin’s initial shortcomings to make it more competitive on the track and on the street. In December 1969, Car Life magazine tried the 1970 Javelin SST and found it much improved.

(Page scans for this vintage road test are by carnut4life at The Supercar Registry.)

Car Life‘s first road test of the Javelin SST in December 1967 had been generally positive: They liked the styling and the flexible 343 cu. in. (5,624 cc), and they thought the interior accommodations and brakes were pretty good. However, there were various minor complaints: The four-speed’s ratios were badly spaced, handling was mediocre with the heavy-duty suspension, and the dashboard’s big slab of plastic was a little off-putting. These weren’t catastrophic faults compared to pony car rivals, but there was definitely room for improvement, and since AMC was a newcomer to the sporty-car market, they needed every advantage.

Some Javelin shortcomings were addressed in short order (for instance, the less-than-ideal gearing of the optional four-speed was rectified by 1969), but there were more extensive changes for 1970: a more powerful new tall-deck version of the optional 390 cu. in. (6,384 cc) V-8, a new front suspension, variable-ratio power steering, a revised dashboard, and an impact-absorbing windshield. The 1970 Javelin wasn’t a new car, but it was in most respects a better car than the initial ’68.

 

Car Life admitted they hadn’t set out to test this car — they had actually been after a Hornet equipped with the new tall-deck 360 engine, and when that fell through, they had been promised a Javelin with that engine, only to get the 390 instead. This is an important reminder about most magazine road tests: While the editors may talk about carefully selecting “their” car, most test cars come from manufacturer press fleets. A magazine may ask for a particular powertrain or combination of options, but the test cars aren’t special orders, and sometimes what the editors have in mind just isn’t available.

 

Although Car Life attributed the new front suspension to the needs of the Trans-Am racers, AMC adopted it line-wide for 1970, and it was long overdue, finally discarding the archaic upper trunnion joints for upper and lower ball joints and new geometry providing more anti-dive and better roll resistance. The new variable-ratio power steering (still a $102 option) was faster than before, with 3.2 turns lock-to-lock rather than 4.2. Car Life found the changes highly worthwhile:

The steering and suspension deliver before you’re out of the parking lot. Effort is reduced, turns are reduced. Best of all, the car responds. This is a subtle sensation, but the car points when the wheel is turned, while AMC cars used to tuck, roll and sort of make vague motions in the direction the driver had in mind.

Pitched into a corner at speed, the front end pushes. … But it doesn’t mush or slide. The front wheels hang on, and the rear wheels track around. Coming out, power gets to the pavement without waltzing the back into a spin.

 

With the front suspension geometry finally joining the modern world, AMC was able to rethink the spring rates for a more compliant ride. Car Life observed:

[T]he handling/ride mix shows an increasing sophistication. The old way, no matter what factory, was to get more grip by cramming monstrous springs beneath the standard chassis. Earlier Javelin handling packages did it that way, and the cars stuck pretty well, but the ride jiggled. Some of the slalomists didn’t even bother to order the handling package. The SCRambler was the stiffest American ever made. A very rough ride, and it didn’t handle all that well, even then. The test Javelin had the handling package that comes with the engine, but the spring rates for it (and most of this year’s AMC line) are 15% lower than for a comparable package in the past. Bumps are soaked up, jars aren’t noticed, and the handling is better than ever.

I unfortunately don’t have complete AMA specs for the 1970 Javelin, but if the data panel’s spring rates are accurate, they don’t bear out the text’s assertion that the wheel rates were reduced by 15 percent — compared to the 1969 specs, it looks like the test car’s front springs were stiffer and the rear springs a bit softer. However, Car Life felt the suspension had been softened sufficiently that hard cornering now presented some tire clearance problems:

The only drawback noted during the test session was that the factory was caught up in some optimism regarding the size of the fender well. With the car at the limit, the big tires graunch against the fender trim. Extreme conditions, and if it happens on the highway you’re going too fast, but somebody should have checked into this before the demon testers did.

Since the wheels and tires on the GO package were the same size as before — E70-14 tires on 14x6JK wheels — this seems like a lack of communication between the body and chassis engineers, an unfortunate lapse for an otherwise improved chassis setup.

 

The 1970 390 engine had the same displacement as before, but for reasons of production economy, it shared the taller block of the new 360 cu. in. (5,892 cc) and 304 cu. in. (4,987 cc) engines, which had a longer stroke for more torque and lower hydrocarbon emissions. (The 390 would be replaced by the longer-stroke 401 for 1971.) There were also new heads with freer-breathing “dogleg” exhaust ports, new intake and exhaust manifolds, and a bigger Holley carburetor. AMC rated the tall-deck 390 at 325 gross horsepower and 420 lb-ft of torque, compared to 315 hp and 425 lb-ft for the short-deck engine. Car Life felt it was still “not what you’d call a racing engine”: It was tuned for torque rather than peak power, and they found it reluctant to rev higher than 5,000 rpm.

(Incidentally, the AMC 390/401 shared the same basic block as the 290/304 and 343/360. It was a bit heavier than the smaller-displacement engines, but it didn’t unbalance the chassis the way a big-block engine unbalanced the Mustang, Camaro, or Barracuda.)

 

The revised dashboard was significantly better-looking than before — not difficult, considering the earlier dash’s unrelieved expanses of cheap plastic, which the text said had drawn complaints even from AMC salespeople — and the trim was much more tasteful. Car Life remarked:

There is very little trim, and the upholstery, rugs. etc., are attractive. … Cushion height and the angle of cushion and back struck us all as about right. The steering wheel goes up and down. too. as it doesn’t in some cars we could mention. (That means [the E-body Dodge] Challenger.) Nice big dials. Rather more warning lights than we like, and there’s an awful lot of plastic wood on the dashboard. but why try to sweep back the tide? The controls are simplified, too. and even a non-AMC owner can manage to make the heater work.

 

In their initial road test two year earlier, Car Life had made no mention of rear seat room, which AMC, somewhat foolishly, had tried to promote as a Javelin advantage. The editors now said:

You won’t believe this, hut the back seat has room for real people. A grown man can sit back there and his head doesn’t bump. The passenger in front can set his footroom to his liking, and the rear passenger can put his legs in front of him. Amazing. It there is anybody who mourns the loss of the slightly bigger Barracuda, the spirit lives on, in the slightly taller Javelin.

 

 

This space advantage didn’t extend to the trunk — the price of the short deck demanded by pony car fashion trends:

 

Although the tall-deck 390 was supposedly more powerful than before, the performance numbers told a different story. The SST 390 launched well with the 3.15 axle and automatic, and AMC had managed to greatly improve the manners of the Borg-Warner Shift-Command automatic (which Car Life had harshly criticized in their road test of the 1967 AMC Marlin), but the Javelin still wasn’t very fast by muscle car standards:

• 0 to 30 mph: 3.5 seconds
• 0 to 60 mph: 7.6 seconds
• 0 to 100 mph: 19.5 seconds
• Standing quarter mile: 15.11 seconds at 91.5 mph

Compared to CL‘s four-speed 1968 SST 343, the 390 car was 0.5 seconds quicker to 60 mph and 0.3 seconds quicker through the quarter mile, but the trap speed was down 1.5 mph. This suggests that the new 390 had more torque but no more power than the earlier 343-4V. Roger Huntington later estimated this car’s as-installed net output at 250 hp, down about 40 hp from the theoretically less powerful 390 in the 1968 AMX.

If you weren’t interested in drag racing — and many pony car buyers were not — this was still perfectly fine, and Car Life called the mild 3.15 axle “just what we’d pick: A compromise between fuel mileage and interior wear, and acceleration at passing speeds.” With the optional front discs, the Javelin stopped okay as well, probably due in part to the new suspension’s greater resistance to brake dive. If you wanted more go, there was now an extensive array of hop-up equipment — a surprising amount of it available over the dealer parts counter — that would have been unthinkable in the George Romney days, including dealer-installed rear axle gears up to 5.00 to 1.

 

The changes for 1970 were not dramatic, but they were further evidence that AMC was really trying, even if selling sporty cars still didn’t come naturally. Unfortunately, this didn’t pay off in sales: The 1970 totals ended up being 28,210 units for the Javelin, 4,116 units for the two-seater AMX, dead last in the shrinking pony car field. That brought total three-year production for the first generation Javelin/AMX to 143,143 units, just barely edging out the 1967–1969 Plymouth Barracuda to become only the second slowest-selling pony car of this era.

For that reason, it’s tempting to regard the Javelin as a failure, and perhaps a wasted investment. Its market share was always negligible, and it was certainly no commercial threat to the Mustang or Camaro. However, there’s another way to look at it. While the Javelin may not have sold well in absolute terms, I daresay most of its business was conquest sales, and it was business that AMC desperately needed. Before the Javelin debuted, AMC market share had plummeted from about 7 percent for the 1961 model year to 3.07 percent for 1967, half the market share of the 1967 Ford Mustang. The Javelin and AMX didn’t improve things by much — AMC market share hovered at around 3¼ percent during their first generation — but they arrested the decline, and they accounted for 18.1 percent of total AMC sales during this period.

 

Without these cars, there’s every reason to believe AMC market share would have dipped below 3 percent by 1968 and continued to fall, probably ending in liquidation not long afterwards. In that sense, the Javelin was something like a parachute. It didn’t really reverse AMC’s descent, but without it, the company would almost certainly have faced a much harder landing.

Related Reading

Vintage Car Life Road Test: 1968 AMC Javelin SST – Praising A “Dramatic And Successful Design Turnabout” (by me)
Vintage R&T Road Test: 1968 American Motors AMX – The Gremlin’s Predecessor (by Paul N)
Curbside Classic: 1970 American Motors Javelin SST – Wrangling A Non-Average Pony Car (by Eric703)
Vintage Snapshots: Javelins In The ’70s – A Gallery of Owners, Riders & Families (by Rich Baron)
The Sporting American: The AMC Javelin (at Ate Up With Motor)