With 1800hp on tap, Aaron Fitzpatrick’s Datsun 1600 is one pocket-rocket not to be messed with

This article on Aaron’s Datsun was originally published in the August 2017 issue of Street Machine

AARON Fitzpatrick’s latest Datsun 1600 was supposed to be a quick fixer-upper while his giant-slaying Street Machine Summernats Grand Champion-winning orange 1600 was with Trevor Davis for six months getting painted. But that’s not quite how things turned out.

The Japanese-style plates might be just for show, but they’re still pretty special. The 68 at the top is for the Datto’s year of manufacture, while the character on the left states the area where the car came from. The 1600 is known in Japan as a 510, while the diagonal red stripe indicates it’s a special interest vehicle

When Aaron picked up this two-owner GL, the original intention was to give it a quick makeover. “It had been stripped, panel-beated, painted in HOK Passion Purple and rolling on FR17s,” he says. “Most of the interior was there; all it needed was an engine and gearbox and it would have been done. Except the orange car came back from Trev’s and I’d spent all my money – so it was pushed into the corner.”

Although the custom Clover Plum the car now wears looks kinda brown, Aaron’s Datsun 1600 GL is known as the ‘purple car’ within the Fitzpatrick clan, as it had been painted HOK Passion Purple for nine years

Over the next nine years there was only modest progress on the car as marriage, children, an HK Kingswood ute and a turbo VP ClubSport took precedence. Then a mini-disaster struck when Aaron’s brother Daniel dropped his motorbike onto one of the quarters. But in true Fitzpatrick style, instead of just fixing the small dent, Aaron decided to completely redo the entire car. After all, having already built one Datsun 1600 into a super-elite show-stopper, a race-inspired streeter should be a walk in the park.

A change of colour was a given, as Aaron didn’t see the point in having two brightly coloured Dattos. Troy and Clayton Hillier were keen to paint the car, so Aaron dragged it 12 hours up to the Hilliers’ Tenterfield shop. “Troy and Clayton are legends,” he says. “Steve Polglase and the Hilliers fine-tuned the body and did a great job on the paint.”

The colour is Aaron’s own HOK custom mix, which his dad Peter has dubbed Clover Plum.

The 2.0L four spins to 9500rpm and makes 750-800hp thanks to strong components that can handle 35-40psi of boost: Arias forged pistons, steel Tomei conrods and a fully studded top and bottom end. Amazingly, the stock steel crank remains, while the head was extensively ported and houses a set of oversized Ferrea valves

What made things really snowball with this build was the decision to tub the rear end. They didn’t muck about, stretching the arches wide enough to swallow 275mm of sticky Mickey Ts. “It’s tubbed very similar to the orange car,” Aaron says. “I smile every time I park the two tubbed Dattos together.”

Big rubber needs big power. The original L1600, and then an SR20 implant, were both scrapped in favour of an insane Nissan FJ20 four-cylinder out an R31 Skyline. “I’d been talking to Paul at ProFlo Performance about this engine for about five years,” Aaron says.

In Paul’s words: “It’s similar to [Paul Hunter’s] MR TRX engine, which made something like 650rwhp at Horsepower Heroes. This one is a little different, as you always use the things you learn in your last build. Its BorgWarner S366 turbo is larger, and it’s dry-sumped. It should be good for 750 to 800hp at the crank.”

That trick sump is all Aaron. Using Artcraft Signs’s 2D cutter, he engraved the Fitzpatrick logo into 3mm flat sheet, which was then rolled and folded before being TIG-welded into a CNC-cut 12mm flange. Presto! A unique, one-off piece that didn’t cost the national debt

For its size, the FJ is quite heavy; in fact it’s heavier than an LS1. But its iron block is near-bulletproof. Squeezing the FJ20 into the 1600’s engine bay called for a custom CPC billet intake and 90mm throttlebody. While smoothing out the bay, Aaron pushed the firewall back, modified the strut towers and grafted in a new tunnel for gearbox and sump clearance.

“The engine bay is actually better than the orange car,” Aaron says. “There’s months of work in there. We were also never going to paint the underside. But we did.”

Managing all that grunt and enabling the little Datto to run stout numbers is a Jatco three-speed auto by Keas Automatics – along with one of the company’s seven-inch billet-base converters. The ’box is the same as a VL, minus the overdrive. Further rearward is a dramatically shortened 31-spline BorgWarner diff spinning 3.9:1 gears, Truetrac centre and 31-spline axles.

On the street YLD510 runs 20-25psi of boost on E85 – which Aaron has found can vary significantly. This Microtech flex-fuel sensor safeguards the engine by detecting ethanol levels and automatically adjusting the tune accordingly

With credentials like this, the chrome-moly ’cage (with bolt-in intrusion bars) and ’chute are not just for good looks. At the track, the number plate folds down and the ’chute slots straight in.

Flanking the fuel cell is the dry-sump tank and the surge tank for the EFI system

Everything in the race-inspired interior is custom – nothing from the original build survived. The billet mount for the Microtech dash is one of the many trick pieces Aaron whittled up himself. He also fashioned the steel dash, rear seat, flat floors and centre console. Aaron and Shaun at Trims By Shaun thought a hexagonal stitch pattern for the trim would be a neat idea, so a Perspex template was cut for marking chalk lines on the cloth, which Shaun followed with the sewing machine – free-hand! It was a nightmare, apparently; Shaun hopes never to have to do it again.

The leather and suede-clad FTO buckets were modified to fit in with the car’s overall race theme, though creating the hexagonal stitching was a nightmare. The front legs of the ’cage are hidden in behind the trim work

By late-2015, Aaron was getting over pushing the car around on dollies. It was time to finish the thing. “Dad, Dan and I got together and set our sights on MotorEx 2016. There’s nothing like a deadline to fire the belly and smash it out. We did a ton of work to make MotorEx, including loads of fab work and countless CNC bits. Dad spent weeks making all the Motorsport Connections dash lines, while Mark Sant from Ontrak did the wiring. We worked on it most nights and weekends and were still finishing it the night before heading to Melbourne.”

The whole Fitzpatrick clan looked very relieved Saturday morning at MotorEx when the Lycra-clad ladies slid back the silk cover on the car to rousing applause.

Typically a 7200rpm converter would be way too big for the street, but with the FJ’s usable power up to 9500rpm, modern converter technology and the way stall multiplies with boost pressure, it all works. “You know it’s got a converter, but it’s not ridiculous,” Aaron says, “I can just putter around”

The goal for the project was to build a tough street car capable of running very respectable times. With a couple of dozen kilometres on the odometer, that’s one box ticked, and Aaron is looking to cross off the other in the next few months – watch this space!

AARON FITZPATRICK
1968 DATSUN 1600 GL

Paint: HOK Clover Plum

ENGINE
Type: Nissan FJ20 2.0L
Heads: Heavily ported, 1mm oversized valves
Turbo: BorgWarner S366
Cam: 296 degrees, 12mm lift
Valve springs: Nismo
Pistons: Arias forged
Crank: Stock balanced
Conrods: Tomei
Intake: CPC billet
Throttlebody: CPC billet 90mm
Injectors: DeatschWerks
ECU: Microtech
Ignition: Microtech CDI with ICE leads
Oiling: Aviaid three-stage dry-sump
Sump: Fitzpatrick Speedworks billet
Exhaust: Owner-built stainless steampipe, 3.5mm dump
Radiator/intercooler: PWR custom
Pref fuel: E85 (street), methanol (track)
Power: 750-800hp on methanol

DRIVELINE
Trans: Jatco three-speed
Converter: 7200rpm stall
Diff: BorgWarner 31-spline, 3.9:1 Truetrac
Tailshaft: 4in Altra9 chrome-moly

SUSPENSION & BRAKES
Front: Lovells coils on custom 180B struts
Rear: Parallel four-link, Lovells coil-overs
Brakes: VL Commodore Turbo discs (f & r)
Master cylinder: Wilwood under-dash pedal box

WHEELS & TYRES
Rims: Intro; 15×4 (f), 15×10.5 with beadlocks (r)
Rubber: Mickey Thompson 24/5.00/R15LT (f), Mickey Thompson ET Street P275/50/R15 (r)