What Is Overboost?
In a world full of downsizing and turbocharging, manufacturers have listened to the plight of us petrolheads and have decided to add in some fun features to keep us all satisfied with the motoring experience. One such feature is ‘overboost’, a feature that is becoming present in hot hatches like the Ford Fiesta ST and VW Golf GTI Clubsport.
It’s a fairly simple concept that brings some much needed drama to the fairly linear power delivery of modern turbocharged vehicles.
The ECU is programmed to set the turbocharger to full boost for a given period of time, sending around ten percent more power to the wheels as the turbocharger forces air slightly faster into each cylinder. In the case of the new Golf GTI Clubsport, power is upped from 261bhp to 286bhp for a 10-second window. This is perfect for a quick overtake or for getting the maximum drive out of a corner on a race track.
VW says that this temporary function is to aid fuel consumption and add performance without having to re-engineer engine components to withstand a higher boost pressure all of the time, but there might be some marketing shenanigans at play here.
The small burst of power puts the Clubsport perilously close to the 300bhp Golf R, therefore it would make sense to keep the standard power output down to 261bhp to not step on the hotter hatche’s toes. So, Would you buy the GTI with this temporary boost on tap or would you spend the extra cash and go for the full-blooded Golf R?
Although overboost may seem like a bit of a con, it’s heart-warming to know that car manufacturers are keeping performance as a priority while engines are getting smaller and cleaner in the war against emissions.
Comments
2011 onwards Volvo T4 engines had that. Not exactly hot hatches either
My Opel Coupe OPC from 2001 already has this feature, 0.9bar and 1,1 overboost
I like boost. :)
Moog explained this more simply on Unicorn Circuit
Overboosted boris?
Oh, so it’s a scramble button.
The real issue here is whether or not the ECU is locked out. If not then there’s plenty of fun to be had. Would still take Golf R because AWD
I was expecting a much more technical thread than this … I R dissapoint CT.
Nothing new though. Chrysler did this in the eighties with their turbo four cylinders.
Here in Australia, we have our ford falcon xr8 sprint, 345kw supercharged 5L coyote v8 with overboost with about 15% increase in power for 16 seconds? Every gear, now I don’t know about you but I beleive the only gear that may last 16 seconds would be 5th after you get to the speed limiter with 6th still to go