Basically, a turbocharger (or turbo) works by using the exhaust gases produced during combustion to spin a turbine. This turbine is attached to another one on the intake side which increases air flow to the engine. This increased flow of both fuel and air means an increased power output.
When it comes to giving your vehicle that extra kick to get it off the line, the first thing most people think of is a fat ol’ turbocharger.
More and more mainstream vehicles are coming standard with turbochargers for increased efficiency and power, as they’re really the best option for directly increasing the power of an engine without having to make significant changes to the engine block itself. They’re also a popular option for modifiers, as you can see above. As with anything though, you have to take the good with the bad, and with turbo comes the sworn enemy of gearheads worldwide: turbo lag.
For those out there who are a little more unaccustomed, basically a turbo works by using the exhaust gases to spin a turbine. This turbine is attached to another one on the intake side which increases air flow to the engine. More air going into the engine = more fuel going into the engine = more POWEEEERRRRRRRRRRRRRR!
The problem with this is that the exhaust turbine, being a mechanical piece, not automated by anything and therefore subject to the universal laws of motion, takes a while to start spinning. In turn, it takes longer for more air to be fed into the engine, and the boost in power that comes with it is not only delayed from when you hit the accelerator, but also comes in a sudden lump. Naturally, this isn’t ideal. Goddamn it physics, always ruining it for everyone.
This can happen on any car that has a turbo, from a TDI Polo, to the most ridiculously modified cars out there. There are however ways around it, and it doesn’t involve just fitting a bigger turbo.
Your first bet is to install a Wastegate. These attach to the exhaust housings on the turbo mount to help get rid of extra exhaust pressure. This allows you to shorten the exhaust housing, meaning the exhaust is fed into the turbo quicker and spools the turbine faster. This is totally legal, and you can even grab one direct from the supplier right here.
IF! And this is a big if, you’re using your car strictly for drag racing at an actual raceway, you can fit a NOS system. For anyone who’s seen The Fast and the Furious, this is the go-fast-make-loud-things-happen-and-win-the-race button on the steering wheel. Basically, a NOS System injects Nitrous Oxide into the engine, cranking up the pressure in the cylinders and in turn lessening the time it takes for the turbo to spool by (apparently) up to 400%. Please be careful though, if you’re engine isn’t tuned to handle it, you’re just going to ruin everything, and Vin Diesel will come after you about that 10 second car you now owe him.
NOTE: IF YOU LIVE IN QLD OR WA, THIS IS TOTALLY ILLEGAL ANYWAY. IF YOU LIVE ANYWHERE ELSE, DISCONNECT THEM WHILE YOU’RE DRIVING ON THE STREET. DON’T BE AN IDIOT.
Apart from these two add-ons, there are a few more complex things you can do. If you’re well versed in the ways of tuning the finer points of an engine, adjusting the ECU for a more narrow power band will help. The less time it takes for the engine to rev up, the less time it takes for the turbo to start turning. Aside from that, you could add in another turbo to spool at lower revs. This is gonna be expensive though.
Keeping your turbo working properly and efficiently is one of the easiest ways to make any turbocharged engine work as well as it should. If you’re after pure performance, hopefully some of the above tips will help you reduce that retched turbo lag that’s the scourge of so many passionate motorists.
When it comes to anything as complex as a turbocharger (as well as any car mods for that matter), make sure you do your research, use the right tools for the job and get the parts designed for your vehicle. If you need any more technical assistance, feel free to get in touch.