Predator fed: Frank Ruiz’s blown HG Monaro

With a blown 350 at the business end, this magic Munro is bound to make your day


First published in the September 1989 issue of Street Machine. Photos: Gartside

The HG Monaro bodyshell is simply a classic. Unless, of course, you think like Frank Ruiz, of Beaconsfield, just outside Melbourne. You see, for blokes like Frank, even a HG Monaro can’t be considered a classic until the hollow bit at the front has been crammed full of 350 Chev. Blown, of course.

In other respects, Frank’s car is straight HG Monaro and from some angles it even looks like a bit of a sleeper. There’s nothing in the interior that gives the game away and there’s no wild paint scheme. Frank’s car is like the quiet bloke down the pub. The bloke who doesn’t ogle the barmaids. The bloke that doesn’t throw up on the cars parked outside. The bloke who doesn’t brag about his bank balance or anything else. But he’s the bloke who carries a loaded .45 Magnum in his jacket.

So what makes this otherwise unassuming (if you ignore the blower and big bore exhausts) HG tick? The story starts with a company you’re probably well aware of. Canberra’ s Pulford Racing Engines has a reputation for bolting together some of the meanest, toughest motors ever to spin a crank. The boys at Pulford’s have built more than a few of the engines featured in Street Machine and that’s who Frank turned to when the time came to re-power is rather tired Munro.

Pulford’s spannerman Ray started with a 350 Chev block with the much sought affer four bolt mains. Into that was bolted a steel crank, but not before it had been magnafluxed and tuftrided in the interests of a bulletproof bottom end. Conrods, not surprisingly, are Chev Pink items and are held together by SPS rod bolts. Arias pistons are fitted to give a pretty pedestrian static compression ratio of 7.5:1. Pedestrian, of course, until you realised Frank’s supercharged plans. The bottom end is completed with stainless steel piston rings and a Crane Commander camshaft. Lifters and pushrods are from the house of Speed-Pro.

Up top, the valve springs are Crane as are the 1.6:1 roller rockers, making the most of that big cam. The heads are Chev units that have been match-ported and flow-tested. They’re fitted with 2.02-inch Milodon intake valves and 1.6 inch exhausts, The valves have a swirl polish design and are one-piece items. Oiling is taken care of by a Chev big-block pump. Believe us when we tell you this thing is tough.

Way up high – through the bonnet even – is the focus of everyone’s attention. The GM blower sits on a Weiand inlet manifold and cops the whirly freatment from a GMC 6/71 blower drive. And doesn’t that make a lovely racket?

Keeping the fuel up to such a motor is not easy, so Frank has fitted twin Predators, two Holley Blue pumps and twin fuel regulators. Nothing is left to chance. And if keeping the fuel flowing sufficiently is a problem, so is getting rid of the small block’s bad breath. That’s why Frank has fitted headers with a two-inch primary system and four-inch collectors. That’s all run out the back into a neat pair of twin pipes. Lighting the big bang is a Mallory ignition complete with the popular liquid-filled coil.

Channelling. all that mumbo rearward is a Turbo 400 tranny with all the good bits, including a full manual valve body and 2500 rpm stall converter. The tailshaft was ripped from a GT Falcon and feeds into a nine-inch rear complete with 28 spline axles. Frank prods at all this via a stock shifter in the stock GM console.

Rather than stay with the Ford rear brakes that came with the diff, Frank has opted for a set of late model Torana drums. Brakes at the pointy end are the tried and true HQ discs while the whole lot takes its cue from a standard HG master cylinder.

Now there’s an important physical phenomenon to be appreciated here. When you attempt to put God knows how many neddies on to the footpath through such a bulletproof driveline, things can get ugly. So you’d better be sure the rest of the chassis is feeling good about life. In the case of Frank’s car, that’s a foregone conclusion because he has taken the time to fiddle around and arrive at the best set-up.

Rather than stay with anything remotely standard, Frank dialled up the Pedder’s hotline and ordered a set of springs and 90/10 shocks for the front end. With that taken care of, the hybrid rear end was suspended by a set of Bathurst-spec leaf springs and a pair of heavy-duty Pedder’s dampers. You bet it handles.

So Frank had what amounted to a missile that actually stopped and handled. Now it was time to make the thing habitable. The body was stripped back to nothing and the cherried shell hit with a layer of grey primer. Then, with the Munro standing around a spray booth in its Y-fronts, Frank’s mate Ergan Milanovic took aim with a spray gun full of Silver Fox. The result, as you can see, is restrained but definitely first class all the way. It doesn’t scream at you and it doesn’t try to grab your eye. But it does because it’s so subtle. Get it? Yeh, that’s right, we’re talking quality — like the difference between David Jones and Target. The stuff might look the same, but look a little closer and you’ll see why one costs more.

Inside, the story is much the same with Frank opting for stock style and materials but with the emphasis, again, on quality. The seats, door trims, console and roof lining have all been re-covered in stock vinyl but the job’s been done so damn well, you’d swear it hadnt been touched by human hands. The instrumentation is the more comprehensive GTS variety with the standard Monaro wheel remaining
intact. The only interior concessions Frank has made to the extra performance is a set of SAAS harnesses to replace the rather dinky lap/sash belts that were standard in 1971.

And do you want to know how faithful Frank has been to the HG theme? There’s not even a stereo fitted. Not so much as an AM Roadchief radio with a single speaker. Nothing. Mind you, with all that sucking and whining coming from just ahead of the windscreen, a stereo would be a waste of time anyway.

The Munro has so far consumed four years of Frank’s life but for the first time since he bought the car, it’s approaching what he’ll admit is a finished state. Naturally, a project like this is never finished completely, but Frank’s would pass anybody’s acid test. And how much is it worth? Good question, according to Frank. Of course, quality like this is always hard to put a value on.

Frank Ruiz
1971 Holden HG Monaro

Capacity:Chev 350
Induction:Twin Predators
Blower:GMC 6/71
Pistons:Arias 7.5:1
Exhaust:Two-inch primaries, four-inch collectors
Trans.:Turbo 400
Diff:Ford nine-inch 3.55 gears
Springs:Pedders, up-rated leaves
Shocks:90/10, Pedders
Front brakes:HQ discs
Rear brakes:Torana drums
Front tyres:Michelin
Front wheels:Center Line
Rear tyres:BF Goodrich T/As
Rear wheels:Center Lines
Paint:Silver Fox
Build time:Four years