ROB reckons it’s a pretty sedate car to drive on the road, and who am I to argue? The bloke can ride a stampede of 1100 wild horses without breaking into a sweat. He can think and steer his way through an eight-second pass and say it feels easy. He can wrestle down 1.7 tonnes of big-blocked XB on standard brakes from 250km/h. He does all this in the same car he drives home from the track.
This article was first published in the September 2003 issue of Street Machine
This is Rob Bertolacci’s world where putting the street into Modified Street Blown is as much a passion as making a massive Ford go way too fast.
“We’re talking approximately 1100hp so it’s definitely a big buzz for me,” says Rob, who’s in the nation’s top five competitors in the class, with an emphatic email@example.com. To do the 120km between home and the Willowbank strip, he whacks the airfilter back on and rips out the nitrous bottles, and he’s left with a 765hp, Optimax-burning streeter capable of 10s. Sedate?!
“I don’t knock anyone who trailers their car to the track, but half the fun of these cars is street driving,” he says. “Obviously the performance I get out of it is from the nitrous oxide, which I don’t use on the street, but it’s got enough power without the nitrous to still give you a buzz.
“But yeah, the nitrous really wakes it up! It’s a whole different car with the nitrous activated. It’s a really hard kick.”
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Rob’s been working up to the eights for 17 years, since he bought the then-daggy XB for $1500. He put it together as a six-cylinder driver at first but on his way to register it, he didn’t even get as far as the end of the driveway before he backed up and ripped it apart again. Gotta be a V8, mate.
It was a 351 first, which he drove and raced, but that still wasn’t it. From day one he’d been collecting bits for a 460ci and reading about the simple 505ci strokers being built in the States. He had to do it. He did a basic, cheap build first time, and has upgraded it since with a steel crank and aluminium heads.
He saved a bundle by doing it all himself, and also by buying budget-to-midrange parts, not your big-name stuff. He swears by the Herbert cam, for example, which actually outperforms a brand-name cam he tried recently. And he’s had no unusual failures from anything.
The cam’s specs – 275deg at 50/0.690 – ain’t going to set the world on fire but Rob knows what he wants and why: “It’s as big as I’d like to go to keep the engine reliable and on the street. It does sacrifice power but if the car can’t be driven on the street it’s no good to me.”
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Same deal with weight: “I’ve tried putting the car on a diet but I mean you can only get so much weight out of a car without wrecking it. I wanted to keep the car the way it is – power windows, the full interior. I like the car too much.”
Yeah, it gets like that, eh? Especially after you’ve done just about everything yourself, over so many years. The only job Rob farmed out was the roll cage. He painted it, trimmed it, built the exhaust, everything. Even persisted with the stock suspension until he proved you really can pull eights on a leaf-sprung, flapper-barred rear end.
Mind you, expect to see Wilwood brakes very soon. Rob admits he’s a “bit of a tightarse” but some 1970s stuff just doesn’t cut it at this level.
The whole experience owes him perhaps $40,000 – dirt cheap for this much fun and performance. But you can’t possibly factor in
the time he’s spent.
The performance has come through experience and development. The engine has progressed from 600hp first time out to 765hp and the nitrous system from a fairly gentle shove to a monster kick. Both have more to come.
It even has a ball-crusher strap for that racey feel
“If someone had told me when I was 16 that it’ll eventually run eights I wouldn’t have believed it,” laughs Rob. Nor even 10s back then. But things change. “I thought if I ever hit nines I’d be happy, you know? But then it just kept going. It seemed a bit too easy to make that extra power and it made big jumps down to low nines, and I thought ‘Geez, we’re getting close to eights here’. I’d like to see it run mid eights consistently in the next year.”
The Ford, which has won its class in the Street Machine Pro Street Shootout (nee Performance Streetcar Shootout) numerous times, has its fans, people who love to see a street car driven in through the gates, run killer times and drive home. Some of them ask Rob when he’ll hit the sevens but Rob’s realistic about that – you can tell in his voice he hasn’t ruled it out but he knows it won’t be soon.
“We’ll just see how far we can go with something that’s still driveable,” he says. “There’s no tricks to it. Cubic inches and a healthy dose of nitrous – that’s a pretty good combination.”
GAS ’N’ GO
NITROUS oxide is not flammable, it’s just a particularly good way of stuffing more oxygen into your engine, meaning you can jam more fuel in, make bigger bangs and therefore more power.
Two slightly different bits of hardware do the stuffing: plates and foggers. The former is not exactly a plate but it sits between the carb and manifold and sprays nitrous into the fuel/air mixture. A fogger is a single nozzle that combines fuel and nitrous before releasing it pre-mixed.
Rob built his own plate, which worked well, but now uses a bought-in fogger system which is giving him more speed (a 154.8mph best) but slower times. “The fogger’s much softer on the launch,” he says.
You can run a gentle dose of nitrous and not stress an engine at all, which is how Rob had his old 351 set up. But if you start to play, expect problems.
“I’ve had my fair share of piston meltdowns,” he admits, happily, knowing he’s not Robinson Crusoe there. Nitrous is something you’re always learning new things about, he says. He’s learning now with the fogger and then he plans to begin a new lesson.
“Eventually when the fogger’s sorted out I’ll put the plate back on and see what sort of power we can really make out of it!”
1974 FORD XB COUPE
Colour: Acrylic Super Red
Engine: Ford 460 stroked to 505ci
Carb: Holley 1050
Intake: Victor 460 with custom fogger
Heads: Blue Thunder aluminium
Cam: Herbert 275deg@50/0.690
Pistons: Venolia custom 10.5:1
Gearbox: TH400 non-transbrake by Precise Automatics
Converter: 10in by Converter Shop
Tailshaft: 3.5in steel
Diff: 9in Moser, 35-spline, 3.7:1
Suspension: Pedders (f) and Koni (r) shocks, custom leaf springs
Brakes: Stock plus parachute (Wilwoods for Christmas?)
Wheels: Weld Draglite 15x5 and 15x11
Tyres: Nanking (f), MT 30x12.5 ET Street (r)
Seats: Aerotech Racing velour
Steering wheel: Formulling
Cage: Six-point by SL Fabricating
Tacho: Auto Meter