Losing power over time

[Capra]

I watched an episode of 5th Gear last night, and there was an interesting section on how they increased the power on a 2012 Corsa VXR. The stock power was 190bhp, but overtime this has dropped to 164bhp, with a loss of 26bhp. The Corsa was fitted with a larger turbo and the end results were 210bhp.
I was surprised that this car should lose this much power since it was new.
Which leads me onto mine, as my car is just 1 year newer could I expect to this much of a drop. I will be taking my car up to MSL at some point so I might be surprised at how little my cars performance increases?

Ps with the larger turbo wouldn't they be increasing the turbo lag?

 

[brandwooddixon]

A similar scenario was run on Top Gear. They found that new plugs, filters and injectors recovered nearly all of the lost power.

 

[alexanderfoti]

I watched an episode of 5th Gear last night, and there was an interesting section on how they increased the power on a 2012 Corsa VXR. The stock power was 190bhp, but overtime this has dropped to 164bhp, with a loss of 26bhp. The Corsa was fitted with a larger turbo and the end results were 210bhp.
I was surprised that this car should lose this much power since it was new.
Which leads me onto mine, as my car is just 1 year newer could I expect to this much of a drop. I will be taking my car up to MSL at some point so I might be surprised at how little my cars performance increases?

Ps with the larger turbo wouldn't they be increasing the turbo lag?

I feel that this isn't the entire picture.

Firstly, unless they dynoed the engine out of the car, on an engine dyno, it cannot be that accurate.

As they are dynoing at the wheels, they are back calculating flywheel horsepower using a set % drivetrain loss, at worst this is a guess. It is possible to measure the losses by running down in netural but not many dyno operators do this, and its not 100% accurate anyway.

The only way to paint a 100% accuarte picture, was to dyno the car when brand new, on the same dyno, then do it again 5 years later, and measure the difference. IMO a 26bhp difference is enough to be margin of error.

In addition to all that, a turboed car will have less loss as the engine wears as it has the ability to raise wastgate duty to compensate for lower than normal boost pressures (up to a point). An NA engine may lose volumetric efficiency as it wears etc, but a turbo engine will always be above 100% in this area.

(ps, my ramblings make sense in my head but not so much above )

 

[Blobcat]

5th Gear measure power gains with a laser temperature gauge so I'd take anything they say with a pinch of salt

 

[LostKiwi]

Have to say their 'mods' make me chuckle. About as scientific as standing at the window forecasting the weather for next month whilst wearing a blindfold.

 

[Capra]

Yes, I do find some of their claims questionable, and some just daft. Not why I am watching it again, maybe because some of the members cars have appeared on there. A previous episode was odd, they tested 4 small super cars for value for money, Ariel Atom 3.5R, Caterham 620R, Zeonos E10Rone and a Radical SR1. The Radical is not was even road legal

 

[GlosRichCLK]

I saw that Corsa feature also. I may have misheard it, but wasn't the new power figure less than the figure quoted when new?

I remember thinking at the time, it was a it pointless, and they may have been better to give it a good service, and some injector cleaner etc, rather than spending £1200 on a new turbo.

 

[Capra]

I saw that Corsa feature also. I may have misheard it, but wasn't the new power figure less than the figure quoted when new?

I remember thinking at the time, it was a it pointless, and they may have been better to give it a good service, and some injector cleaner etc, rather than spending £1200 on a new turbo.

the new power figure was slightly more than what it came with from stock. It was odd, it was about reviving power back to the car, and I thought it was odd my increasing the turbo! What makes me laugh is not everyone can fit a turbo! So then you pay a garage to do it.

 

[Botus]

I watched an episode of 5th Gear last night, and there was an interesting section on how they increased the power on a 2012 Corsa VXR. The stock power was 190bhp, but overtime this has dropped to 164bhp, with a loss of 26bhp. The Corsa was fitted with a larger turbo and the end results were 210bhp.
I was surprised that this car should lose this much power since it was new.
Which leads me onto mine, as my car is just 1 year newer could I expect to this much of a drop. I will be taking my car up to MSL at some point so I might be surprised at how little my cars performance increases?

Ps with the larger turbo wouldn't they be increasing the turbo lag?

where is the proof it originally made 190? I guess in the manual. probably based on running illegal software, special petrol all on an engine lucky enough to have been assembled nicely, with parts that were close to optimal spec and then run in well.

the reality is 10% will be good, 60 % average and a load of duff ones, add in 40k worth of dust, burnt oil and other filth blocking the ports, a bit of wear in the valve train, badly run in and a part clogged air filter and 168 was a good day

then we get ambient conditions that could get us 10bhp either side, a dyno that's 5 to 10 bhp out of calibration, underinflated tyres etc.

of course bolting a get big turbo and not worrying on a dyno about lag will get things higher... tip a bit of toluene in the tank for good measure and lets get 500 for 10 mins till the pistons melt

 

[Botus]

wasn't a far better episode where they put upgraded brakes. alloys and tyres on and its lap time was much slower

 

[LostKiwi]

A simple remap would have been cheaper, easier and give more power...