1000rwhp twin-turbo AP5 Valiant

Josh Messineo blended LS grunt, an AP5 Valiant and 80s street machine styling to create a 1000rwhp drag-and-drive weapon

Josh Messineo AP5 Valiant
Photographers: Steve Kelly

Few things will ruffle purists’ feathers like fitting your classic ride with an engine from a rival manufacturer. Josh Messineo knows all about that; he chose to stick a cheeky iron-block LS into the front of his AP5 Valiant.

First published in the July 2023 issue of Street Machine

The intention wasn’t even to upset the Mopar faithful, but rather to find the cheapest and easiest route to a four-digit street car. “The goal was to break the 1000rwhp barrier, and you just can’t argue with how easily we did it,” Josh reasons.

The AP5 has been built as Josh’s new drag-and-drive machine, which he hopes will dip into the eight-second zone. “I don’t like race cars you only use four times a year, so I wanted a car that can run eights at the track but that I can also throw the kids in and go cruising,” he says. “I’ve also loved watching all the drag-and-drive stuff in the States, so I want to have a go here myself.”

After deciding not to use his ’56 Cadillac for such a purpose, Josh went on the hunt for a suitable home for the 5.3, and happened upon the AP5. “I’m not really a Valiant guy, but it popped up as a roller for the right price, so I grabbed it.”

The Val’s chassis copped a decent make-over, with Josh’s vision for the car’s stance dictating a fair amount of that work. “We tubbed it to fit the 275s, but we also made a whole new tunnel so it could sit lower,” he says. “I was chasing a proper tough 80s street machine look, which is why it has the stance, black paint with red leather interior and the Center Line-style wheels.”

Josh and his mates also set up the rear end themselves, which uses an anti-roll bar, leaf springs and CalTracs to suit the nine-inch, while the HBR rollcage was fabbed by Matt Tomasini. “My good mate Mark Tralau guided me through the whole build and made sure we did everything so it only had to be done once and done right, so I can’t thank him enough for his help,” says Josh.

The LS is a fairly basic iron-block deal with a pair of mirror-image Precision GT42s strapped to either side. The engine copped some basic treatment from Robby Abbott to handle boost, including a set of Callies rods, Diamond pistons and a custom-grind John Bewley camshaft. Locking it all in is a pair of stock 243 heads, topped with a Holley manifold.

An Emtron KV8 ECU is the brains trust, and, sipping E85, the combo made an easy 1070rwhp on 24psi via the Turbo 400 ’box. “That was its fifth pull, and once we put the new Trick Flow heads on it, it should see over 1200rwhp easily,” says Josh.

The build only took around two years and was wrapped up around Christmas last year. “Like I said, we did most of it ourselves while hanging out and talking shit, so it’s a pretty stout thing, considering,” laughs Josh.

The car has yet to make a pass down the strip, but rest assured Josh will have those low eights on the agenda when it does. “I’ve been driving it around a bit and just ironing out the kinks, and it’ll hopefully hit the track in the next month or two,” he says.

After that, it’ll be time for Drag Challenge, and the Queenslander is keen to tick a bunch of ’em off his list. “I’ll obviously do [Drag Challenge Weekend] when you guys bring that back up here, but I’ll bring the car down and do the five-day one as well,” he says. “My mates and I have all got cars that can run in that eight-second group, so it’ll be a bit of fun competition between us, and should be an awesome time.”


Class: Haltech Radial Blown

Engine:LS 5.3L
Inlet manifold:Holley
ECU:Emtron KV8
Turbos:Precision GT42
Heads:LS 243
Cooling:AU Falcon radiator
Exhaust:4in stainless
Transmission:Turbo 400
Converter:Pete Nichols
Diff:9in, 35-spline axles, 3.5:1 gears
Wheels:15×5 (f), 15×8.5 (r)
Tyres:165/80R15 (f), 275/60R15 (r)

Mark Tralau; Simon Vorst; Charles Krogdahl at 2J Auto Electrics; Matt Tomasini for the ’cage; Robby Abbott for the engine; Knight Family Motorsport for the tune; my son Fin