Five sleepers with wicked engine swaps that worry the big boys.

These five rides may look innocent, but secretly they’re high-horsepower hot rods looking to embarrass much tougher-looking machinery.


Tuners have been doing the small-car, big-engine thing for yonks, so it’s not surprising that more than a few tiny Smart Cars have been wound up over the years to deliver some embarrassing strip times. With a rear-engine, rear-wheel drive layout, motorbike engine swaps are the popular choice for tuners wanting a muscle-car taunting rocket. And why not strap on a turbo or two while you’re there.

The Smart ForTwo sleeper we found is a little different, packing a 1.5-litre Toyota Paseo engine which ordinarily pumps out 90hp – only a handful more than the Smart’s original 70hp 1.0-litre three-pot. Add a Sprintex blower running 28lb of boost and a three-speed transmission, however, and this beast can worry big V8 muscle cars and run the quarter in the twelves. With a hard launch it also delivers awesome two-wheel action.

On its first run, the Smart popped a big wheelie off the line, which apparently caused a few cogs to shear off its blower belt. It ran a 13.90 at 80.99mph, not quite enough to reel in the 13.67 second Shelby Mustang. On its second run, however, the front wheels were just able to hang onto the strip and the spiced-up Smart recorded a 12.53 quarter at 107.39mph, enough to beat the V8 ’Stang by over half a second. 


To the uneducated, this Buick Le Sabre looks like a boggo green coupe that’s been driven to and from the bowls club for the past 20 years by grandpa. It looks completely original with its Kermit the Frog green paint, green leather interior and period-correct wheels. The only giveaway that this old chugger might be packing some heat is the slick drag radials it’s wearing. And if you pop the bonnet, chances are someone at the drag strip will notice the nitrous injection.

This LeSabre is one hell of a sleeper boasting a 385 small-block Chevy V8 which makes around 400whp as standard, or over 700whp with the nitrous engaged. That’s enough grunt to get this old retiree down the quarter mile in nine seconds. It’s a total stealth rocket. But it can still be daily driven because it retains the original air-conditioning and interior luxuries.

Here it runs a 9.85 second quarter at 133.82mph – not bad for a big girl. Even without spray it scoots along at a very decent lick with an 11.89 second pass at 113.51mph.


The Willys Jeep is possibly the scariest hot-rodding platform around. The lack of doors and roof, combined with the high centre of gravity, bench seat and lack of any kind of protection from, well, everything is horrific. And when you add in a supercharged nitrous-injected LS motor putting over 750hp through the rear wheels, you can guarantee things are going to get sketchy.

This Willys uses a 292ci LS motor with a D1 Procharger supercharger and Nitrous Express spray system to deliver over 750hp. With the throttle mashed it easily picks up the front wheels, which makes launching the thing tricky. When done right, though, it’s a proper rocket capable of a 9.88 second quarter-mile run. That sort of performance means the Willys has gained roll-over protection and serious seats with harnesses over the past few months.

The wild Willys rides on Summit Racing steel wheels wrapped in M/T street radials, but the suspension is mostly original 1952 Jeep – which explains the scary lift-off. In the rear it’s packing 3.73 gears. Engine management is by a DIY tune Megasquirt ECU. 


There are plenty of LS V8 Commodores at the strip, but with the right bits the V6 motors can kick just as hard as their bent eight brothers. Case in point is this old ’98 VT Holden, which hasn’t been built to look special or attract attention – it’s all about functionality and speed. Its demure exterior earns it sleeper status and when it’s not rolling on drag radials you’d have no idea this Commie was a nine-second scorcher.

Beneath the bonnet is a balanced and blue-printed 4.2 stroker V6 motor with one massive custom turbo making 688whp, which hits the ground via a Trimac three-speed gearbox with 3800rpm stall converter. At the rear it runs the standard Holden independent suspension with a custom 3.4:5 diff. The six-pack has enough grunt to lift the front end, but those massive rear radials hook up nicely and she sets very quick strip times.

Here the V6 bruiser scrapes into the nines, with a 9.92 second quarter mile run at 143.86mph running on pump fuel wearing the recently installed X275 radials. And it delivers those figures on the standard engine block. 


POP666 is one mental HQ Holden. Even with broken steering this thing ran in the eights, slithering down the drag strip with only slight control. She’s powered by a 510ci big-block Chevy V8 with a big Precision Pro Mod turbo strapped on to deliver 1200hp to the rear hoops. Stuffed underneath is a Powerglide transmission with 3500rpm converter and a nine-inch Ford 3.5:1 diff. This HQ drinks E85 juice with Haltech EFI keeping everything under control.

Owner Harry Haig has got some pretty serious stones, too, man-handling the car down the quarter with broken steering and still setting an astonishing 8.52 second pass at 163mph. To call this thing sketchy would be an understatement. Still, there’s plenty more to come from the HQ as it was running on a low-boost setting when it wandered down the Heathcote strip in 8.52 seconds. Let’s hope Harry fixes the steering and gets a front-end alignment before winding up the boost any further.

Join the Street Machine newsletter to stay in touch with the latest and greatest!