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I have a MkV Golf GT TDi 5-door in Shadow Blue. Apart from a set of 17" Estorils, it's totally standard.

For a while I've been contemplating a performance upgrade and one of
the companies I've considered taking it to is Superchips. I've
made the initial enquiries and I'm fairly happy with what I've been
told about the conversion, the projected power and torque figures, the
price and of course the implications to my warranty and
insurance. For my cash, I'll get 185BHP and about 300 lb ft
of torque, so in addition to the quoted "7 secs 0-60" time (which is
meaningless, really), I'll be into some serious mid-range
performance. Can't wait [H]

When I bought the car, I was under the impression that the 2.0, 16v diesel engine produced 138BHP (140PS) and 236 lb ft
of torque..........but apparently this ain't the case at all. In
fact, it's not remotely unusual for this engine to produce 156BHP and 254lb ft in completely standard, factory trim...

Superchips and other vehicle upgrade specialists are fully aware of
this; they'll quite happily provide evidence to anyone who asks, but
interestingly so are several of the main-dealer service
personnel. What isn't immediately obvious is why this practice of
dramatically under-quoting power and torque figures is necessary, but I
have some ideas:

Given that there is a GTi-spec, "170" BHP version due for launch, maybe
VW felt that quoting realistic output figures for the standard GT TDi
would affect sales of the GTi TD? This makes sense until you
consider that it would've been entirely possible for them to make sure
the car actually produced 140 BHP, as opposed to
156...................but this would have course afected performance,
which in a car weighing over 1400kgs, might've suffered a little.
So they quoted 140BHP, but actually gave it the performance of a 156
BHP car without admitting to it..........interesting...[6]

Other factors could've been the problem of how a quoted 156 BHP
might've affected insurance groupings and also how it would've been
perceived by more conservative buyers, who actually value economy over
storming performance. In Japan, they've been bypassing
legislation and gentlemen's agreements for years by simply quoting
"276BHP" for virtually all their performance cars, when in fact some of
them have been brought over here and tested at 350+BHP, straight
"out-of-the-box", so to speak.

Does anyone have any more info about all this? Are other VW models affected? Just curious...
 

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All manufactures are the same, my Golf TD is 148bhp and 267lb ft and thats just with a panel filter. My previous car a 115ps Focus diesel is quoted as 113bhp, on superchips rollers it produced 125bhp 215lbft then with a chip 146bhp and 235lbft. The 1.6 petrol focus quite often gave 115bhp sometimes as much as 120bhp, the 1.8 and 2.0 petrol ones also should similar increases over standard. Only the ST170 hit 169bhp to 170bhp. I think they take an average power output when developing the engine knowing full well most cars will kick out more than they claim
 

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As posted by Wilko in this topic http://www.uk-mkivs.net/forums/317973/ShowPost.aspx

"But VW rate their engines by taking a batch of 10, running them at full power on an engine dyno for 2 hours, (hot, hot, hot) and then quote the lowest one. It is no surprise that a relatively cool engine will show more than this on a dyno."

My PD150 on standard map was dynoed at Superchips HQ when I bought the car (with 16k) in April 2004 at 165bhp and last week (with 40k) three runs 167bhp, 167bhp and 169bhp.
 

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MINIs too. Superchips quote 100bhp for the published 90 bhp MINI ONE and 123BHP for the Cooper (published 115bhp).

I remember a MINI rolling road day where all the ONEs had well over 100bhp, some up to 108bhp standard.
 

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I read that the Veyron is under quoted for BHP - it makes at least 1000
bhp and I guess because of this its actually limited to 250 mph.

I didn't know the 140 TDi made that much power on the rollers.
 

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I read that the Veyron is under quoted for BHP - it makes at least 1000 bhp and I guess because of this its actually limited to 250 mph.

I didn't know the 140 TDi made that much power on the rollers.
The Veyron is more of a marketing thing because before it was built Dr Peich promised 1000 bhp, it actually runs 50bhp more than this but they left 1000 bhp in the specs as this was what was promised and I guess it sounds a bit snappier!
 

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My 140PD registered 153bhp as standard on the superchips Rolers and then 180bhp remapped, this was then verified at JBS a month later.

My current GTi registered smack on 197bhp on the same rollers pre-remap. I was a little surprised and expected the standard figure to be slightly higher than VW's claim but I guess this just proves the 'average theory' as I have every confidence in the accuracy of the rollers at S/C. The car has only done 2,600 miles so maybe this will have had an impact ?
 

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I am expecting my Veyron to show in excess of 1,000 bhp on Superchips rollers when it arrives.  It should have a conservative 1,400bhp after a mild remap.  I have just got in from the pub.  Goodnight.
 

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My GTI MKV is meant to output 199bhp but it's closer to 210bhp...

I'm considering having a remap, there's a few places that'll do it
varying from 230bhp to (the top one I've seen) 270bhp. Might not
though, I love the car as it is and pushing up past 270 is perhaps just
getting silly[;)]
 

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Guys, some boring stuff you need to know about power tests (I run engines on test beds so this is my subject);

Fact 1. All published max power and torque fugures are measured to an EC regulation that corrects the figures obtained on the day for a standard air temp and atomospheric pressure (baro). The air temp used is 25degC, as UK air temps are usually lower more engine enters the engine so more torque (and therfore power) is produced. So you local dyno test will probably quote a higher figure than you expected.

Fact 2. Published data is measured at the flywheel (we don't need a car to test the engine). Your local dyno test measures it at the wheel, they estimate the losses caused by the transmission, tyres etc, and calculate a flywheel figure. They don't have the actual data for your car so they make an educated guess on losses to get their torque and power figures.

Fact 3. All manuafactures will underquote thier figures to ensure the worst case car (engine) produces the power and torque figures quoted as they can't risk being sued under the trades description act.

Its boring i know, but these are the facts.

Chassis dynos are great for showing changes, if you want to quote the figures get your car tested on a cold day when the air pressure (baro) is high. Keep an eye on the weather forecasts!
 

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Guys, some boring stuff you need to know about power tests (I run engines on test beds so this is my subject);

Fact 1. All published max power and torque fugures are measured to an EC regulation that corrects the figures obtained on the day for a standard air temp and atomospheric pressure (baro). The air temp used is 25degC, as UK air temps are usually lower more engine enters the engine so more torque (and therfore power) is produced. So you local dyno test will probably quote a higher figure than you expected.

Fact 2. Published data is measured at the flywheel (we don't need a car to test the engine). Your local dyno test measures it at the wheel, they estimate the losses caused by the transmission, tyres etc, and calculate a flywheel figure. They don't have the actual data for your car so they make an educated guess on losses to get their torque and power figures.

Fact 3. All manuafactures will underquote thier figures to ensure the worst case car (engine) produces the power and torque figures quoted as they can't risk being sued under the trades description act.

Its boring i know, but these are the facts.

Chassis dynos are great for showing changes, if you want to quote the figures get your car tested on a cold day when the air pressure (baro) is high. Keep an eye on the weather forecasts!
Good post Paul. I would add that dyno operators can input an inaccurate air temperature to show better figures, as well as change air pressure in tyres to reduce slippage on the rollers (plus a few other tricks that I can't remember...)

It is also worth bearing in mind that fuel quality varies across VW's markets so quoted power figures will be more accurate in areas with worse fuel. Most dyno readouts show a typical 2.0Tdi engine producing 150+ but the typical Gti reads 200bhp - ie closer to the manufacturer's quote. Using better petrol should help as the ecu will advance timing accordingly.
 

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The rolling road I use at Star Performance measures the air temp and pressure and ajusts the reading accordingly (is it to DIN 7020 or something?). I can't remember what kind the road is though.

My chipped 115 has been measured twice- the first time it gave 146bhp at 35degC air temp, so it was corrected to 151bhp.

The second time it gave 157bhp at 4degC and again was corrected to 151bhp.

The standard car gave 120bhp (corrected figure).

They also depress the clutch at max revs after the run and let the car go back to idle again, presumably measuring the resistance provided by the drive train to get an estimate of the transmission losses all through the rev range.

It does seem that diesel VW's seem to be more underestimated than petrol versions. Maybe the quality of diesel fuel varies more across the world than petrol?
 

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Yours sounds bang on at 151 with a remap, nice to see some realistic figures being quoted, far too many tuners make some rather optimistic power claims which only leads to disappointment when accurate rolling road days are attended, the proof should always be in the satisfaction the drive provides[:)] The dyno figures just help our egos a little and give us some pub chat [;)]
 

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The rolling road I use at Star Performance measures the air temp and pressure and ajusts the reading accordingly (is it to DIN 7020 or something?). I can't remember what kind the road is though.

My chipped 115 has been measured twice- the first time it gave 146bhp at 35degC air temp, so it was corrected to 151bhp.

The second time it gave 157bhp at 4degC and again was corrected to 151bhp.

The standard car gave 120bhp (corrected figure).

They also depress the clutch at max revs after the run and let the car go back to idle again, presumably measuring the resistance provided by the drive train to get an estimate of the transmission losses all through the rev range.

It does seem that diesel VW's seem to be more underestimated than petrol versions. Maybe the quality of diesel fuel varies more across the world than petrol?
I'm impressed, they guys you are using obviously understand the need to correct data for air temp & pressure an tranmission losses.

Fuels can, and do, vary in quality at the pump but in general its well controlled. We use forecourt grade fuel for most of our testing switching to reference fuel (at ?4 / litre) only when we need to.
 

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Anyone thought that maybe its because we are overestimating drive train losses?

A figure of 20-25% seems to be the norm on all rolling roads ive seen -
it strikes me that as technology moves on that will get less and less.
Especially with emissions getting tighter and tighter that 20% is alot
of wasted power!
 

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Anyone thought that maybe its because we are overestimating drive train losses?

A figure of 20-25% seems to be the norm on all rolling roads ive seen - it strikes me that as technology moves on that will get less and less. Especially with emissions getting tighter and tighter that 20% is alot of wasted power!
Sorry mate, its unlikely to change, that 20-25% loss is down to friction in the drive train (transmission gears, bearings, drive shaft joints and tyre defection/distrotion). Tyres are hard to imrpove, less friction = less grip, do you want that?

Mechanical friction absorbs a lot of power. Here at work we can motor engines over and measure thier friction. I recently measured the running friction of a V8 engine at 7250rpm (its for a new luxury sports coupe), it was just over 75kW (approx 100BHP). Given we are alway looking for ways to increase engien performance and fule consumption if there was an easy waay to reduce friction we would. Imagine, if we could reduce this engine friction by just 25% it woulf have an extra 25BHP!
 
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