Flashback: TUF58 XY Falcon V8

We look back at Nick Karathanasopoulos's brutal XY GT

Photographers: Warwick Kent

We first featured Nick Karathanasopoulos’s TUF58 XY GT Falcon in the April/May 1992 issue of SM, under the title ‘Shock Treatment.’ It then scored the cover and another feature in the June 1994 mag, this time dubbed ‘Urge Overkill,’ no doubt lifted from the then-trendy grunge band of the same name.

Here’s the full feature from the June 1994 mag below:

Some cars deserve a double-take. The second we clapped eyes on Nick Karathanasopoulos’ diamond cut XY GT Falcon at Summernats 6, we just knew it deserved a place in the hall of fame. When he rang recently and said he’d made some minor updates, we jumped at the chance to put ace photographer Warwick Kent on a bomber to the Gold Coast to re-capture Nick’s SuperFalc.

It’s a special four door Ford all right, and not for obvious reasons. Like the fact that all the rubbers, clips, lights, moulds and other ittybits are all original FoMoCo stock.

Nick chanced upon a gold mine when he heard of a bloke getting out of his Ballarat GT Falcon shop to live up north, and Nick made an offer on his entire remaining stock. “I took home a truck load of bits — it was easily enough to rebuild six or seven GTs!” says Nick.

But small detail isn’t all that makes this GT a true Ford. That live axle at the back’s a nine-inch, cut down by a total of 5 1/2 inches to accommodate mini tubs. It carries a limited-slip centre, and a holeshot hero 4.56:1 ratio. And those tubs, incidentally, caused Nick a few dramas.

“Most people say you can’t do fuel injection with superchargers on the street. I wanted to prove them wrong”

The first bloke screwed up big time, so Nick and his mate Darren hooked into it themselves. And the engine bay was lead wiped rather than bogged; after a heap of hard launches on the strip in its previous single carb form, Nick reports no cracking beneath the lid. Factory sunroof and mini-tubs aside, it’s the same pristine GT Falcon body Nick stripped back to bare metal six and a half years ago.

You’ve probably noticed the partially exposed powerplant, but what you won’t glimpse is the hard shifting Ford C6 auto behind it. The valve body’s been fully manualised, which means Nick’s hand is reaching for the B&M Quick Click shifter on a regular basis. It all makes good sense when you consider the massive torque output from a 600 horsepower Cleveland.

“I really wanted to run injection,” says Nick. “Everyone has blowers through carbies, and most people say you can’t do fuel injection with superchargers on the street. I wanted to prove them wrong.” He has. As part of the car’s most recent update, Nick had Russell Jones – Winfield Top Fuel driver Jim Read’s engine builder – pick up some parts in the US.

The barrel valve was worn on the Enderle Bugcatcher system, so Jonesy bought a late model system with splined linkages. The old stuff tended to slip, which was causing inconsistent idle. Tuned right up, the injection system’s capable of delivering a staggering 3000cfm of intake flow, although it’s doubtful Nick would use even a pinch of this on the street. A Holley Blue pump feeds an avgas/Super mix to the header tank up front, with an overflow back to the main tank.

“The GM superchargers need some work when they come off trucks,” says Russell. “You have to put heavy duty end plates on them, particularly if you’re going to run with big boost on the strip.” As purchased, Nick’s blower had a home made style end plate, which Russell ripped off quick smart, as well as re-setting the tolerances on the vanes. Super grade fuel causes higher blower temperatures than methanol, so the clearances must be kept reasonably wide to allow for expansion.

Nick’s GT is running the 6/71 huffer 10 percent under-driven, which equates to between 10 and 12psi of boost pressure. That means while static compression ratio is just 9.4:1, this jumps to a respectable 12:1 on full boost, which is why lower compression open chamber heads – O-ringed, with Fel-Pro gaskets — are used.

Something Nick will have to contend with, says Russell, is deteriorating bore condition. Aside from lubrication problems, high performance Clevelands are renowned for splitting bores, mainly due to a lack of meat between the bores and the water jacket.

For now, Nick’s enjoying the fruit of his labours. How many of us get to drive a dream? “Everyone loves getting attention,” he says, “and I just love having something that goes as good as it looks. I wanted something that could win car shows and kick arse on the strip.” And for the people who wonder why he’d build a marginal streeter, Nick issues a challenge…

“Come for a drive with me into Surfer’s Paradise; I’ll drive past the cop station, park and drive back out. If all this car did was sit in the garage it might as well be someone else’s. You’ve got to be able to drive it.” “Fightin’ words … tuff car.


Induction:Enderlie fuel injection
Blower:GM 6/71
Intake man:Weiand blower manifold
Exhaust:2 1/2-inch dual
Diff:Ford nine-inch
Springs:King’s; reset leaves
Shocks:90/10; 20/80
Front brakes:‘91 Ford discs
Rear brakes:Stock drums
Front tyres:Goodyear Eagle 265/50
Front wheels:Simmons V5 15×11
Rear tyres:Pirelli 345/45
Rear wheels:Simmons V5 15×13
Paint:Glasurit Track Red
Build time:3 years