10 Laps in a Works PRB
by Bruce McCabe
Practice day at Winton, preparing for the 1999 6-hour race. Still learning the fastest way around this delightful track. There are large puddles of water standing around the dirt tracks in the paddock from the previous day's rains, but the weather has improved greatly, and sunshine is bringing much needed heat into the day. It is clubbie heaven in the Flavios Boys tent, with yellow, green and red PRBs shoehorned into every available space. I've managed to mostly dial-in my car, but still have some changes of the front bar to try. Contemplating this when Chris Barry comes up and asks me if I would like to take his car out for a few laps. The front bar can wait.
Chris' car, as many readers will be familiar, is one of the quickest PRBs running. Originally built in 1993 for the East West challenge in Western Australia, PRB 14 has had an enormous amount of development put into both chassis and motor. The powerplant is getting close to a Formula Atlantic spec 4A-GE and puts out about 200hp at peak revs. It is fitted out with a lightened flywheel, Tilton racing clutch and close-ratio gearbox with straight-cut gears.
By way of comparison, my very own PRB-19 has spent most of its life as a road car and has been progressively sorted for racing over the past year. It is very close to stock with a standard 4A-GE motor putting out somewhere around 115hp. My drivetrain, with the exception of a ceramic clutch, is essentially standard, with a vanilla, road-going Toyota T-50 gearbox. On top of all these differences, there is a weight difference of almost 50kg between the two cars (no prizes for guessing which one is lighter!)
Apart from having as much fun as can be had standing up, this was a fabulous opportunity to contrast a fully race developed Division 1 PRB with its Division 2 counterpart. Just to ensure the comparison was as complete as possible, I had not been able to organise new wheels and slicks in time for the weekend, so I was running Street-TD road-race tires on 6-inch rims. Chris's car was sitting on lovely wide Avon slicks wrapped around 10-inch rims at the back and 8-inch rims at the front. Stock versus worked, weekend warrior versus thoroughbred racer, standard Toyota power versus 4A-GE on steroids. Whatever you call it, it was an opportunity not to be missed!
The first question to be answered is whether I will fit. Chris and I both weigh about the same, but I am taller and the seat is molded to Chris' body shape. Dropping myself into the cockpit I find myself suspended in mid-air by my hips with about an inch of clearance under my backside and my knees wedged firmly under the dash. After extricating myself we look for another solution. The molded seat comes out and the knee problem disappears. Too much room now, so we employ the bottom half of Peter Taylor's seat as a backrest and buckle in.
Then come the rules of engagement. Don't slip the clutch says Chris, you will burn it out real fast - let it out directly. No problem. Keep the revs to eight grand please, he says, as he wants to preserve his motor for race miles as much as possible. OK (reluctantly). Respect the brakes, they come in strong with very little pressure. Respect the power .. Chris is actually smiling and relaxed all through this (especially considering that he is entrusting his pride and joy to me here) but by the end of the conversation I am beginning to think PRB 14 is going to be an intimidating son-of-a bitch to drive! Finally, Chris asks me if I have earplugs. Who needs 'em - I cant think of a nicer way to go deaf .
Push button start, with a tad of throttle and she fires up. Select reverse, a little throttle and drop the clutch. Stalled. Wanker! Redo all the above and get a push back out of the tent. Chris jumps on the back, use more revs to get some wheelspin and we head off up to the dummy grid. Lumpy bastard idling up the bumpy surface in first gear, chugging forwards and backwards almost enough to throw Chris off the back. He leans over and suggests politely that I try second.
At the dummy grid. I've got enough fuel and the OK from Chris for about 10 laps or so. The marshal waves me out. Game plan: first lap to get used to the car, second to get some rhythm going, then build up the speed and find the limits.
Head out onto the short start-finish straight before driving sedately through the two third gear right-handers. Changing up through the gears is a doddle. Car feels very firm, brakes feel natural enough, clutch is very light, much lighter than most racecars and even most road cars I have driven. First lap goes past quickly even though I am easing it through the corners as if I was going around Winton for the very first time.
Second lap. I begin to take the revs up, push harder under brakes and build up cornering speeds. Overwhelming sensation of how easy the car is to drive! Steering is VERY light, in both slow and fast corners -- much lighter than I expected given the size of the tires. Like the clutch, the brakes require very little pressure before they bite, as Chris warned, but they present no difficulty. The throttle pedal is positioned almost exactly where I put mine, so blipping for the downchanges comes naturally. So much for the intimidation factor.
With renewed confidence I begin to push much harder, taking revs to my self imposed redline on every upchange and bringing the braking points forward. Heaps of fun through the tight series of right-lefts through the back section of the track. A week ago, the V8 drivers were complaining about how tight the circuit is for their cars, but these bends are pure joy for clubbie drivers, allowing you to get the car sliding like a go-kart. The lightness of the steering on PRB 14 continues to amaze, all I have to do it look at each apex and the car seems to turn itself in with no physical input at all! A little extra throttle on the exit from Repco onto Dunlop straight finds the limits of rear traction, with a repeat performance onto Falken straight. I restrain myself on the much more slippery entry to the main straight. There is a very clear powerband and the engine gives the overwhelming impression of having no load at all between 6 and 8 thousand rpm, spinning up in the blink of an eye. Sharp, healthy blasts of noise as it gets up through the gears ever so quickly. Each time the clutch bites and the right foot snaps down there is a satisfying shove in the back and a surge in speed which is no less impressive in fourth than in any of the lower gears.
The straight-cut gears and the way they engage remind me of a Formula Ford box with the feel they provide, although the throw is longer. It rewards, no, demands fast upchanges. I oblige happily, flicking the lever faster on each shift, although for several laps conscious thought is required to break habits formed driving my own car. The downchanges also require some additional concentration, as the blips I use in my car would bounce this free revving engine off the limiter.
Hit the brakes much later at the Motorsport esses and feel the car begin to squirm. It remains almost completely level and pulls up hard, but without losing any traction, despite the uneven surface here. Makes me appreciate how well sorted the dampers and springs are. It will take me several more laps to build up to the limit here. Wonder what Chris will say if I flatspot a couple of Avons? The esses are a great part of the track, requiring trail braking right up to the first apex, followed by a quick and aggressive application of the throttle, for fast times. The blast out is an absolute joy with all the extra power, and once again the steering is never compromised and you can't help but nail the apex. The lightness suggests you could dial up serious oversteer on turn-in to some of the corners, but this never seems to happen. Indeed, Chris says he uses aggressive steering, rather than braking, to wash off speed into the slow corners at the back of the circuit.
Heading into the fast sweeper. A little lift on the way in (ignore messages from my brain insisting I touch the brakes) grit the teeth and hold on for the very late apex, staying off the marbles on the outside. Push the cornering speed up higher and the car begins to move about noticeably on the tires. The feedback tells me that I am approaching the edge of traction but I know this is unlikely. Indeed, high speed cornering is the one area where I have to admit never finding the limit on PRB 14. I increase speed through the sweeper a little more on each consecutive lap, but never take it beyond this phase, which is probably will within the natural slip-angle of the Avons. I don't know how much heat I have managed to get into them so they are unlikely to be working at optimum grip levels, and I certainly cannot afford to spin off the outside of the sweeper and risk cutting tires, cracking a sump or worse just wouldnt do when we need this car to win on Sunday! Another issue, which only seems to matter in the sweeper, is that my makeshift seat is moving about far too much in the cockpit and I end up being shunted from one side of the car to the other several times by the time I get to the entry to Penrite!
For the last few laps I try to push harder everywhere. Love to know what laptimes I am doing: they are already MUCH faster than I was doing in PRB 19. Overtaking cars is enormously fun. It seems the only effort required is to stand on the throttle and take avoiding action as they come back into your face like they are standing still (Mental note to ask Chris if this ever gets boring!!)
Using the brakes more aggressively sees the time in the braking zone come down rapidly and it becomes harder to match the revs when shifting down from fourth to second (there is definitely no time to do fourth-third-second!). I can feel the gears begin to clash as they go in and I am determined to treat Chris' gearbox with kid-gloves, so more than once I take the soft option and choose third for slower corners.
Braking extra late at the end of Dunlop straight the car wiggles and squirms and creeps to the left - easily corrected in the steering. A sure message that the rear tires are working hard under braking, but a sensation sadly absent in Division 2 cars, which have to make do without adjustable brake bias.
As the corner exit speeds come up the maximum speeds increase as well, and the airstream buffets my helmet towards the end of each straight, requiring a conscious effort to keep the head forward. I get this phenomenon in my car only on the much longer main straight at Eastern Creek, giving me the sense that I am easily hitting similar speeds on Winton's much shorter straights.
The 10 laps are gone very quickly, and I peel off the circuit and trundle up the dirt road to our tent to find Chris grinning with delight. He has never listened to the sound of his engine at full noise from anywhere but in the cockpit and thinks it sounds pretty damn good. Needless to say, I am also grinning from ear to ear (now I know why Chris uses the term "grin-factor" so much) as I jump out. I assure Chris that I took good care of his beastie, kept the revs to our agreed limit and did all the right things. He says he knew that I would, while at the same time sneaking a quick look at the telltale (8100rpm) just to be sure!
No doubt, like all cars, it becomes more challenging to drive as you really begin to approach the ragged edge, but the most amazing thing about PRB 14, and the strongest lingering perception, was how well it was set up for the driver, making it an absolute delight to drive. To have built a clubbie that is so quick, but that still remains so unbelievably easy to drive, is perhaps the best possible measure of how much work Chris has put into developing this car.