Julian Edgar, 50, has been writing about car modification and automotive technology for nearly 25 years. He has owned cars with two, three, four, five, six and eight cylinders; single turbo, twin turbo, supercharged, diesel and hybrid electric drivelines. He lists his transport interests as turbocharging, aerodynamics, suspension design and human-powered vehicles.
Added costs of turbo/blower
When Japanese import engines and gearboxes first started flooding into wreckers, I can remember writing cautionary tales spelling-out the fact that while the engines were incredibly cheap, by the time you got one installed in a car and had provided engine management, engine mounts, radiator modifications and sometimes a new tailshaft, the price may well had gone up three or even four times. These days, with many engines available with uncut looms and the factory ECU, you could probably reasonably budget on a doubling the in-car price.
And a similar price multiplication also occurs for individual engine parts.
Over the last few months I have fitted firstly a Japanese-import supercharger, and then latterly a Japanese-import turbo. Both were installed on a car that is normally naturally aspirated. And rather like the old days of buying cheap engines, I’ve found that the main cost of both the supercharger and turbo conversions hasn’t been the initial cost of the blower or turbo, but instead all that is required to accompany it.
The little supercharger cost me $250 from a wrecker, while the turbo was even cheaper. (All dollars are Australian.) Hell, that’s good value! In both cases, the devices were in excellent condition and compared with buying new, represented savings of hundreds and hundreds of dollars. In fact, you could get very excited walking out of the wrecker with one of these in hand….
But you really need to budget at least another $1000 to get either a supercharger or turbo into a car and working. And that’s doing as much work as possible in your own garage at home…
Take the supercharger first. I am not going to give a quantified blow-by-blow account of the costs, but a few examples will make the point. In my case, the required supercharger support bracket was complex. It was also time-consuming for the welder who cut out the plates used to form it and then welded them together. His labour cost was something like $500… and I reckon I spent maybe four times as long working on that bracket! (The supercharger bracket had also to do double duty as an engine mount.)
Then there were the drive belts. Because the shape of the bracket changed several times during the build – so moving where the idler/tensioner pulley was to go – the required belt length also changed. To check clearances and precise belt lengths, a new belt was needed each time – as a result, multiple ribbed belts were bought. At about $40 each. Then there was the new airbox – another ex-wrecker item but still costing dollars – and the intercooler. Add the plumbing, fasteners (Allen-key bolts for the supercharger plumbing flanges, high tensile bolts for the supercharger mount), paint, insulating lagging, rubber hose bends, hose clamps (was it ten of them?) and the total soon added up. I was using the Digital Fuel Adjuster kit and hand controller to tweak the amount of extra fuel, so that cost was low – but still another $140. Even the oil change I thought prudent for the supercharger was another $15.
And fitting the turbo was much the same story. By doing all the work myself (except the welding) on the turbo exhaust manifold, the price was kept down to $500. Since the intercooler was already in place for the previously installed supercharger, that part of the project didn’t need any more expenditure, but keeping things fair, budget another few hundred for the core and plumbing. The custom-made high pressure oil supply line was another $100, the oil return fitting for the sump $40, the turbo coolant hoses another $30. High tensile fasteners (turbo flange bolts and nuts, stainless steel Allen-key fasteners for the compressor housing) $20, stainless steel sheet for a heat shield another $5. Again, all these prices are as low as possible – the stainless was from a scrap metal dealer, for example.
Again, it can be seen that in round figures, another $1000 is needed.
It’s also important to note that a lot of these costs aren’t immediately obvious. The high tensile bolts for the supercharger, the high quality sealant used to re-seal the sump after it was removed for the fitting of the turbo oil return line – I certainly wouldn’t have included these in any costings made before the project was started.
In absolute terms, these are still very cheap projects. In fact, realistically, I doubt whether it’s possible to decently supercharge or turbocharge and intercool a car for much less. But just because you can pick up a wrecker turbo or blower for very little, don’t then assume that the cost of the whole project will be similar to that initial expenditure. In fact, it’s likely that the cost of the turbo or supercharger will need to be multiplied by four or five times to have a working on-car system.
Just like it used to be with bare engines, really.
