LS-powered Factory Five Shelby Cobra Daytona replica

Gavin Irvine built his Daytona Cobra replica with his own two hands. The result is a beautiful tribute to an automotive legend

Photographers: Troy Barker

As you probably know, they only built six original Shelby Cobra Daytonas. Even if you do find one for sale, it’ll cost enough to cause a heart attack, so if you want one of your own, your only option is to go down the replica path like Gavin Irvine did with his stunning, LS-powered Factory Five Shelby Daytona.

First published in the March 2023 issue of Street Machine

This isn’t Gavin’s first time with a Shelby kit car, having already built an LS1-powered Shelby Cobra for himself. Unfortunately, that car met a nasty end on track, which prompted Gavin to build the Daytona you see here. “I always liked Daytonas when I still had the Cobra, and when I had to say goodbye to that car, I decided to build one,” he says.

This particular car is a 1965-spec Factory Five Racing replica that Gavin sourced from the US. “I built the Cobra myself and really enjoyed it, so I wanted to do that again with the Daytona,” he says. “I have a decently equipped workshop from my work as a gas and electric fitter, and I find building these cars after hours a relaxing thing to do.”

Gavin’s Daytona landed in pieces from the US in late 2016, and from there he began building his dream machine. “The kit comes with everything but the engine, gearbox, steering rack and tyres, but I’d already planned some changes anyway, so that didn’t faze me,” he explains.

One of those big changes was the engine, as Gavin had no intentions of using a Windsor V8, which the Cobras were originally designed for. “It would’ve been a lot simpler if I did, but I already had the LS there, and I kind of like annoying Ford guys as well,” he laughs.

Specifically, the LS is an iron-block LQ9, and she’s by no means a junkyard throw-in. Gavin gave the mill a full renovation with beefier internals, even throwing the crank away for an Eagle stroker, accompanied by a set of Eagle rods, Wiseco pistons and a Comp Cams stick.

The heads are LS 241s that’ve had a 30thou shave, but the coolest bit of the whole deal is the EFI Hardware vertical eight-stack ITB manifold. “That was a gift my wife bought for me, and it’s a beautiful piece of gear,” says Gavin. “They work really well and give the car that old-school look while still having modern EFI reliability, so the engine is the best of both worlds.”

The LS is paired with a TR6060 manual ’box, and during the mounting process Gavin moved the whole lot a good four inches back. “I did it to improve the handling, and moving it back was mainly just the mounts; I didn’t have to move the firewall or anything like that,” he says.

Recessing that LS was worth the effort, though, as Gavin scaled the Daytona and came back with a pretty-much bang-on 50/50 weight distribution.

Completing the driveline is a three-linked, 8.8-inch live-axle rear end, shortened just enough to comfortably fit the 15×10.5 Trigo pin-drive wheels and 295/50 Avon CR6-ZZ retro rear rubber. “I love those tyres because they have the old-school look but are still very sticky,” says Gavin.

Given that a decent part of this Daytona’s purpose is to hunt tarmac both on track and twisty roads, we should pay a mention to the suspension and underpinnings. Factory Five will supply the car in right-hook configuration, but it’s a BYO deal for the actual steering rack. Gavin also wanted power steering, so after some research, he landed upon a rack pillaged from a TF Cortina. “I also converted it to an Astra electric power steering pump, as the LS pulley system had to be fully changed to fit, and the whole system works beautifully,” he says.

Koni adjustable coil-overs live under all four corners, and the brakes are discs you’d normally find on a Fox-body Mustang GT. “They still fit under the 15-inch wheels and work well,” Gavin says.

The car took around six years to complete, and Gavin reckons the only real struggle he had throughout the process was the bodywork. “I changed lots of little things along the way, but getting the body lines right was one of the bigger challenges for sure,” he says.

One big impetus for Gavin delving back into the Shelby world with the Daytona after his Cobra’s demise was the club meetings and people he’s met through the Australian Shelby scene. “I’ve met so many great people through the process of building and owning both cars, so that’s why I wanted to do another,” he says.

That means the Daytona has to do a lot of road miles, so Gavin did add a few small creature comforts to suit. “It has a/c and seat heaters, and I built it so it can be driven,” he says. “We did 1000 kays in it recently, and even just last week, we took it out for a Sunday adventure. When I have the time, it gets used – that’s for sure.”

As for Gavin’s future plans with the Daytona, they’re pretty simple: “Just wash it, use it and enjoy it,” he says. “I’ve got an early 911 that my youngest son and I are going to start working on soon, so that’s the next project. The Daytona is perfect how it is; I’m really happy with how it turned out and love using it every time I get the chance.”

Gavin Irvine
1965 Factory Five Racing Shelby Cobra Daytona replica

Paint:VW Iceland Green, Wimbledon White stripes
Brand:416ci GM LQ9
Induction:EFI Hardware vertical eight-stack
Heads:LS 241
Camshaft:Comp Cams
Crank:Eagle 4in stroker
Oil pump:Comp Cams
Fuel system:Bosch 044 pump
Cooling:Aluminium radiator
Exhaust:Tri-Y, mild steel
Gearbox:Tremec TR6060
Converter:Mal Wood clutch
Diff:Ford 8.8in
Suspension:Koni adjustable coil-overs (f & r)
Brakes:Mustang GT discs; 310mm (f), 290mm (r)
Master cylinder:Wilwood
Rims:Trigo pin-drive; 15×8 (f), 15×10.5 (r)
Rubber:Avon CR6-ZZ; 235/55R15 (f), 295/50R15 (r)

My beautiful wife, Josie; The B Club; Bobby Brown at Shoalhaven LS Tuning & Performance; Brendan at Riordan’s Paint & Panel.