Interesting dyno results

[ukgroucho]

Surely 0 to 60 time is meaningless as the engine is simply accelerating the rollers to 60 mph (albeit with some resistance) and not a 2 tonne vehicle... There has to be some mass / momentum / inertia calculation at play here?

[Whippy53]

Surely 0 to 60 time is meaningless as the engine is simply accelerating the rollers to 60 mph (albeit with some resistance) and not a 2 tonne vehicle... There has to be some mass / momentum / inertia calculation at play here?

Correct, the only way is via a stop watch.

[fest0r]

Official stats

309 bhp / 313 ps
481 lb-ft / 650 nm

Actual

327 bhp / 331.5 ps + 6%
516 lb-ft / 699.6 nm + 7.4%

With tuning box

349.6 bhp / 354.5 ps + 7% (over actual)
570.4 lb-ft / 773.4 nm + 10.5% (over actual)

Very interesting. Going by their advert I’m not sure how TDI-Tuning work out 754 nm to be 572 lb-ft. Using various online calculators and working it out manually I get 754 nm to 556 lb-ft and 572 lb-ft to 775.5 nm. Am I going mad or is this an error with their figures? Any feedback from them Jamie?

http://www.tdi-tuning.co.uk/car_and_...rds_P7049.html

As for the 0-60 I have Torque Pro (with OBD BT adapter) and RaceChrono to try when I get a chance and a dry day

[ukgroucho]

I don't know ? But i do want to measure the 0-60 accurately. Any suggestions ?

Dynolicious works well for iPhone - costs £6 or thereabouts I think... that's how I got this info (it will also do a BHP estimate). I've seen it used by a motoring journalist


Dynolicious 1013.jpg

For android I have "Not only car performance" (free) but not tried it.

in both cases the phone needs to be secured so it cannot move.

[AGW82]

I don't know ? But i do want to measure the 0-60 accurately. Any suggestions ?

Get yourself one of these http://www.racelogic.co.uk/Store/pro...ceBox-%252d-01

[wja96]

It looks like the box is giving a pretty linear response. You put x throttle input in and you get x+a fixed amount, so the mapping is similar to what you would expect with a straight over-fuelling system.

The narrowing of the curve could be where the turbos change over, or it could be a change in camshaft profile. Whatever it is, the engine is adding less fuel or air (or both) and the box is still adding the fixed amount, so you get slightly less at that point. If the box knew the revs of the engine, you could add a bit extra at that point in the rev band and keep the increase the same throughout.

There's certainly a decent hike in torque, you should be able to feel the extra, which isn't always the case.

As suggested, it probably is worth increasing the fuelling by going up a stage on the box and keep going up until the ECU light starts to come on then back off one or two stages.

And it's good to know that even a tight engine is giving 20bhp over the claimed output. They loosen up and improve considerably after the first couple of services.

[Whippy53]

Of course, a faulty dyno, who didn't I think of that. Obvious when you think about it.

[fest0r]

You missed my post above?

They are quoting Audi’s figures for the “before” power/torque on their page and I doubt their test car(s) were running bang on the official output. Regardless, the actual stock output from your car should be the “before” to work from and with a car well over official output you should be guaranteed to hit their figures… especially as they’re happy to advertise the jump from the lower figures. Blaming ecotunes equipment doesn’t quite ring true to me either. The torque is what they expect, but the power is down on the same run? It would also mean your car would have to be putting out around 353bhp stock to get the same 7% and take it to their 377bhp figure… and still nowhere near their advertised 22% bhp increase.

I also don’t agree with their conversion from nm to lb-ft on their tuned figures. It can be a few out depending how you do it, but it’s around 20 out by my calculations. Am I making an error?

Also, did you try changing the user adjustable engine settings?

[retired99]

The manufacturers figures are almost certainly obtained from a bench mounted engine, well calibrated equipment and all factors which could affect engine output (fuel, temp, pressure, oil viscosity , ancilliaries fitted etc.) controlled.

Trying to work back from figures obtained on a probably uncalibrated dyno with no control over other factors and a guesstimate of transmission losses is not going to deliver an accurate / comparable result.

What is useful, however, is before and after figures. These should indicate the level of change.

As fest0r pointed out the torque / power conversions on the TDI site are suspect.
TDI state 754 Nm equals 572 lb ft; it actually equals 556 lb ft.
TDI state 377bhp / 382 ps equals 290kw; it actually equals 281kw.

While there must be some competent / professional people in the tuning business much of the industry doesn’t fill me with confidence.

[ukgroucho]

Ok Some feedback and also info about the A7 & A6 gearbox debate.

A7 & A6 same variant of box but running different software.

Which derivative?