First published in the December 2004 issue of Street Machine

Nine-second timecard is something to be proud of and this one-tonner holds the Australian LS1 record at 9.81@140mph, set just in time to get into this issue of Street Machine.

Aside from the timecard, twin turbos and metre-long flames from the open exhaust signify that this is no ordinary LS1. Housed in a tricked-up tonner body with a fully fabricated rear end, this is no one-off drag special. Rather the Dynomotive/APS tonner is a road car reality and a rampaging showcase for APS’s brand new twin turbo LS1 kit.

“It all started innocently enough,” Dynomotive proprietor Mark Trouson laughs. “I bought it as a parts getter for the workshop and in the space of six months it’s turned from a practical daily driver into a Powerglide-equipped, quarter-mile burner!”

Yet the twin turbo package can be an everyday driving proposition as Trouson proved with his epic hike from Melbourne to the Sydney Holden vs Ford Show, driving the stock diff and six-speed manual equipped tonner there and back, returning fuel economy better than 10 litres per 100km.

“That’s the beauty of the twin turbo system,” says Mark. “When you don’t want the power it’s not there. When you’re cruising at 100km/h it’s off boost and running like a stocker.”

But crack the throttle and even in fifth gear the twin boosted LS1 strains at the leash, threatening to light up the rear treads. “Yeah, the trip to Sydney was an interesting one as it was the first time we’d really driven the car on the road.”

And how did the tonner go in Sydney?

“We won the Holden vs Ford dyno shootout first time,” Mark says, “but it was a bit of a struggle. Testing in Melbourne, we had an easy 700+ horsepower at the rear wheels but in Sydney we registered 688.4hp and took first place by 0.3hp over the CAPA Crewman. If we’d needed we could have gone further but I didn’t really want to overly stress the stock engine. It’s a long drive home!”

Stock engine? Pretty much. Under the FAST inlet manifold, the hydraulic 230-degree camshaft and the ported big-valve cylinder heads is a stock set of LS1 conrods and cast pistons.

So how does the engine live with such a load? According to Mark it comes down to cushioning pistons and rods with the turbocharged boost pressure. “Turbos are easy on conrods so you can run high boost without the same engine load as other types of forced induction.”

That doesn’t mean Dynomotive will build big power APS twin turbos with stock reciprocating bits. “Any insurance is good so at 700rwhp outputs we’ll be advising a built bottom-end,” says Mark.

The twin turbo tonner’s been transformed from hay hauler to track mauler with mods making use of its half-chassis construction. Mark’s mate Sean Mullin designed rear slapper bars to control axle tramp, fabricated a rear-end to house the magnesium locked centre, and tubbed the tray for those 30-inch slicks. Then Mark matched the Powerglide two-speed auto to the alloy Chev, hooked up the transbrake and got on the track.

Witnessing the tonner’s first quarter, its awesome torque and potential were obvious. On its maiden run Mark trod gently, fed the power in slowly from a soft launch and pedalled the side-stepping truck all the way down the straight. Silence. Then cheers as 10.54@134mph lit up on the time boards.

“The best part about it,” Mark reckons, “is that we were only at about 60 per cent potential!”

The proof of that comment came soon afterwards with the nine-second pass. Having shattered the old 10.22@139mph LS1 record, you’d think Mark and APS would be looking to up the ante even further. Maybe not.

“I think I might just put it back to being a twin turbo road car,” Mark reckons, “and use it for daily driver, pick-up duties.”

If he does, it’ll be the fastest parts delivery in Oz!

LS1 TWIN TURBOS

APS mounts the turbos in its new LS1 kit down low, behind the steering rack. While this doesn’t offer much in the way of visual impact when the bonnet is lifted, APS boss Peter Luxon reckons you can’t beat it from an engineering point of view.

“It basically keeps heat out of the engine bay while still getting maximum efficiency from the turbos,” he says. “If you look at the way Lingenfelter has done this with his Corvette kits in the States, the concept begins to makes sense.”

The intercooler is a superb bar and plate item, measuring up at 540x250x150mm. The canted, dual entry end tanks ensure that the charged air from the turbos is spread evenly through the ’cooler core for maximum efficiency.

Luxon reckons the kit has more potential, saying: “We have up to 65lbs per minute of airflow available from each turbo, giving a maximum theoretical output of over 1000hp.”

DYNOMOTIVE/APS
TWIN TURBO 2004 VY ONE-TONNER