The 1991 Isuzu Impulse RS couldn't have been wound tighter if it had been powered by an extra-caffeine eye-opener cappuccino with a Mountain Dew chaser, but hey, that's what made it fun. Isuzu had replaced the earlier rear-drive Impulse with a new front-driver for the 1990 model year, spinning off a variant called the Storm for GM's then-new Geo division. That first year's model, called the XS, was fine, with Lotus-tuned suspension and a little green "Handling by Lotus" badge on its fender to prove it. But torque was lacking, the 1.6-liter putting out a healthy 130 bhp but only 102 lb-ft of twist, and that at 4600 rpm.
One should have known Isuzu had an answer ready: turbocharging. And an intercooler. And all-wheel drive. The Impulse RS. The engine, of course, was the heart of it, the DOHC 1588cc 4XE1-T boosted to 160 bhp and 150 lb-ft of torque, though the latter came at a lofty 4800 rpm. The engine was mounted transversely, the air-to-air intercooler nestled horizontally between the valve cover and the left inner fender. A NACA scoop in the hood rammed air over the 'cooler at speed and also distinguished the RS from lesser Impulses. Distinctive alloy wheels were mounted with 205/50VR-15 Bridgestone Potenza RE93 rubber.
Still not sure? Across the tail, Isuzu lettered "all wheel drive/intercooled turbo." The RS was otherwise similar to the XS, sharing the retractable "eyebrows" over the round quad headlights (the Storm had rectangular lamps), and both Isuzus coming with integrated foglamps in the front spoiler.
The XS could clip off the quarter mile in a respectable 16.3 seconds, but the RS lowered that to 15.8 seconds The RS also gained slightly on the skidpad; it shared a rigid L-shaped lower-arm strut suspension with the XS, but the RS had a unique multilink rear suspension. The standard four-wheel disc brakes also hauled the RS down better than the rest of its class...and more expensive sports coupes. ABS was an option.
With a base price of $14,849, bang for dollar was the RS' strong point. That could easily be lifted to nearly $18,000 fully loaded, but even that was still several precious grand less than the AWD Talon/Eclipse twins.
The Impulse RS, however, had a personality all its own. The only substitute for cubic inches is rectangular dollars, but the latter weren't lavished on the RS, and as a result, Isuzu's coupe had turbo lag by the bagful. The solution, of course, was keeping the motor on the boil. Keep the revs up. But do that and the RS buzzed like an old-fashioned doorbell. It would go if you worked at it, but the manic-depressive power delivery made the RS a challenge to drive in everyday traffic.
On the other hand, driven flat out all the time, the RS was a gas. The Lotus-tuned suspension was sweet and predictable. Said Car and Driver, "The Impulse can be driven right up to and beyond the limits of tire grip, requiring only a high-average degree of skill and concentration. Its chassis is a benign and willing partner on a winding road."
Alas for the Impulse RS, more obedient engines were available in other models, and anticipated annual sales of 2500 didn't materialize. Fewer than 1000 of the 1991 model year were sold. The RS was officially in the '92 lineup, but only one, according to our source, was sold in the United States. The alert few purchasers, however, got to enjoy the caffeine buzz of the RS, which today, ironically, makes it a real sleeper.