For most of its intended market, the 74kW of power and 225Nm of torque possessed by a stock turbo diesel Rodeo would be more than adequate. But when your everyday workhorse needs to be able to tow a larger than normal load, and when it also needs to acquit itself well from the sands of Fraser Island to the dirt tracks of the Watagan Forest National Park, the General's standard specifications just don't cut the mustard.
Bought from NSW's finest at 11 months of age, Denis Klamer's '99 model Holden Rodeo didn't last long in stock form. A passion to head bush "all the time" meant the body went up an inch and the suspension copped an extra two inches of travel. A Safari Snorkels snorkel was fitted (to stop water entering the engine during river crossings) and various accessories that make for an effective 4WD also found their way into the car - communications equipment, fat tyres and an extra battery. And along the way, a few extra Autometer gauges (boost, oil temp and a voltmeter) were added to allow an eye to be kept on the engine's vital stats.
For a while that was enough, but there was a growing realisation that the car was slow - with a capital 'S'. Adding insult to injury, on a certain steep hill near his home, Denis trailed well behind his father's non-turbo 2.8-litre petrol-powered Hilux. Now Denis may be a reasonable bloke, but being beaten by the old man was more than he could bear.
Seeking salvation he went looking for a little bit more power. Eventually his search led him to Dave at Cooma Diesel in Fyshwick, who came highly recommended. According to Denis, "Everyone I spoke to had only good things to say." Dave suggested a number of minor modifications to achieve both power and torque gains, without at the same time building a hand grenade.
Zorst
First step was a custom 2?-inch exhaust and straight-through muffler, with the work carried out by local shop Budget Exhausts in Merrylands. Despite the difficulties in tucking the new system up as close to the body as possible to minimise damage while 4WD'ing, the dyno still showed a massive gain of 18 per cent. In kilowatts, the power jumped by 9kW to 59kW at the wheels (according to Dave, a stock version usually shows 50kW at the wheels).
So how can a new exhaust give an 18 per cent power increase? Well, not all of it was in the better flows - interestingly, the new exhaust also unlocked some more boost. Nothing huge mind you, just a couple of extra pounds - 11 psi compared to the stock figure of 9. Enough, however, to give the car a good kick in the pants. Overall Denis is more than happy with the system, which is almost as quiet as stock and with "no resonances at all".
'Cooler
Two weeks later, the car went into Cooma for the next major step, a brand spankin' intercooler. Given the extra boost being stuffed into the engine, Dave thought this would not only increase power but was also a wise investment in engine longevity. The new Safari tube-and-fin FMIC - measuring 500mm by 180mm and 50mm thick - can be purchased in kit form to virtually bolt straight up. Interestingly, rather than being on either side, the end tanks are actually at the top and bottom of the core.
Given the Rodeo does not come from the factory with any 'cooler at all, the new item was a massive improvement. According to Denis, intake temperature "went right down". Time for another dyno run.....
The results, you ask? Well, as this dyno graph shows, power peaked at the wheels at 70kW - a gain over the vehicle fitted with just the exhaust of another 19 per cent! So, with both mods in place power rose from 50 to 70kW, an overall lift of 40 per cent.
And that's one helluva improvement!
For his small investment of hard-earned, Denis is more than happy with the result - the car has since performed flawlessly for over 6500 kilometres, despite often rough treatment.
More importantly, Denis proudly reports he can now overtake the old man "with ease" up that same hill, complete with trailer in tow!
Contact:
Cooma Diesel:
+612 6280 0178