GTD+

[AMarsh]

So for anyone that had ran the tdi tuning box for any length of time, what is your thoughts?  This is probably controversial, but I'm starting to think that the gtd wasn't a great choice.  I'm pretty underwhelmed by the performance and get 45mpg on average. It neither seems particularly fast or all that frugal.  Does the box at max make it feel noticeabley quicker? 

[monkeyhanger]

So for anyone that had ran the tdi tuning box for any length of time, what is your thoughts?  This is probably controversial, but I'm starting to think that the gtd wasn't a great choice.  I'm pretty underwhelmed by the performance and get 45mpg on average. It neither seems particularly fast or all that frugal.  Does the box at max make it feel noticeabley quicker?

For me, mpg gains? Forget it. You will get false high indicated mpg because the common rail fuel pressure is higher than the ECU thinks it is at any given amount of throttle. You can see this in that the higher the setting is on the box, the higher the indicated mpg gets. The discrepancy between indicated and real opens up from 5% (no box) to 9% (level 4) to 15% (level 7).

Performance is great at the higher end, and throttle response seems so much better - it's like someone woke the car up a bit (standard throttle response feels a bit dead compared to my Scirocco). You won't be able to put that extra power down in 1st or 2nd to get a 0-62 time of 6.5 - 7 seconds (A3 Quattro with GTD engine achieves 6.9s as it overcomes the GTDs traction limitations), but 3rd/4th/5th and 6th gear acceleration is so much better.

Don't expect the car to roar away when you change up and are doing less than 1500rpm just because you have loads more torque, you need to keep the turbo spinning at every change up to get the best out of it. The power increase is predictable - it's not like you half press it and it goes mental now. It's more like they took the standard output on the full throttle pedal travel and condensed it into the first 65% of travel, and then it keeps going some more.

Not entirely sure what TDI-tuning.co.uk did when I sent it back after not getting higher mpg and they remapped it again. It feels like they took a little bit off the top end, not a lot, but it's harder to get the traction control to start working hard in 3rd gear.

To be fair, without changing my driving style, and only giving it the beans (albeit a few extra beans) when I would've done anyway e.g. to shoot straight up to 80mph when entering dual carriageway from a sliproad,I haven't seen my actual (brim method) mpg dip.

Get it for the performance, not for mpg gains - you won't see them unless you take the MFD indicated value as gospel whilst wondering how your car has gone from 47mpg to 55 and yet you're spending the same amount on filling the car.

So it won't be any quicker screaming away at the lights, but it'll be a lot quicker doing 40 to 80+ mph.

The GTD is so much smoother than my Scirocco 170TDI that it doesn't feel anywhere near as quick, maybe it's too refined for it's own good when you want to rag it a bit. If you're sat on the motorway at a constant speed i'm sure you'll be glad of the extra refinement.

[monkeyhanger]

Is there any smoke with full beans and the box fitted ?

Can't see any with full beans, but I imagine that any "smoke" to be seen would be soot and the DPF is supposed to capture all that and combust it.

So I think the thing to ask is “am I getting any extra regens with the box attached?”. At setting 4 I would say no. At setting 7 I am not sure because I had my first regen in ages a day after ramping up to setting 7, and it may have been a huge coincidence.

Mine is back on setting 7 for a few days and my box that got sent back for “tweaking” definitely seems less powerful after I had said to TDI-tuning that I wasn’t getting any mpg gains and traction on my sh!tty Bridgestones wasn’t great. New setting 7 is like old setting 4. I had the opportunity to really give it some this morning (clear and dry road) and the car was noticeably more powerful than stock, but felt nowhere near as powerful as it had been first time around. There was no fear of traction control kicking in on 3rd under hard acceleration this time around. Maybe it was because it was quite cold this morning (3C). I am making a short journey down the A1 this lunchtime – I will give it a bit of a testing today and then if it still feels much less powerful than 1st time around I will contact TDI-tuning to ask exactly what they did to my box when they “reconfigured” it.

Right now I suspect they cut 30-40% off the power gains to supposedly give me more mpg and resolve my traction issues which I blame the Bridgestones for.

Buddy: I wonder whether your dual channel replacement is like my first box or the revised box and whether you notice an appreciable difference with the dual channel vs single channel either way?

[monkeyhanger]

Looking around on the net for other boxes – This one looks intriguing. It claims to work differently from the other boxes. Supposedly it monitors your driving style and it does nothing when driving normally (presumably when cruising/maintaining speed or at moderate acceleration only), letting the car run as per factory settings to minimise potential DPF issues, but put your foot down and it will kick in with “infinitely variable fuel mapping” and give you 231PS and 483Nm max for the GTD. Sounds like it acts far more like a remap than a box.

Reading between the lines, this system implies that other boxes just overfuel at any given throttle pedal travel by increased rail pressure (and boost pressure too, for the dual channel systems) all the time - either crudely (box of resistors £60 ebay job) or by more sophisticated means (the £200+ boxes).

The fact that they fall back on the factory settings for low load driving suggests to me that over the longer term, they don’t think constant common-rail pressure overload is good/advantageous for your car or offers any true mpg gains – which seems more plausible than the claims of higher mpg for the other box sites. The fact that you can stick this on another car that has the same harness connections without reprogramming also seems to add plausibility to its “learning” function and constant monitoring for changes in fuelling demands to act.

Or it could all just be more patter from another business vying for your cash.

I’m giving this one some serious thought seeing as though my TDI-tuning box seems to have had its wings clipped with the “tweaks”. I do like the idea of this box only intervening to provide more power when you want it, but otherwise leaving the car alone. It’s pricier, but comes with a 1 year powertrain warranty and a 5 year product warranty. No messing about with multiple maps of varying rail pressure/boost pressure increase either – 1 map does everything. It’s £375, but comes down to £300 with the discount code “7500”.

http://www.dieseltuning.co.uk/store/index.php?route=product/product&path=128_111_518&product_id=1848


Their product patter:-

Spider® - Advanced design now alIows a pIug in tuning system so advanced, it can actuaIly mould to your driving style.

The Spider® dieseI performance system is the Iatest phase in dieseI tuning technoIogy. No other system on the market is as unique as the Spider®. Superb eIectronic cased in a newly designed Carbon Fiber effect high impact enclosure, complete with originaI equipment connection harness with features the competition can onIy imagine. The Spider® is the onIy plug in tuning system in the worId which uses Adaptivscan™ mapping software to constantIy change its infinitley variable fuel mapping™ to suit the current appIication. At a computation rate of 20,000 per second, the Spider® can compute and adjust its fueI mapping to a Ievel so precise, and can deIiver performance at a level of quaIity so high, it can compete with "Iive mapping" whiIst remaining removabIe and transferabIe to your next car. InstaIlation of the system is performed using an originaI equipment connection harness which simpIy plugs into existing connectors on your cars Ioom. The Spider® is then stored within the engine bay of the vehicIe, but can be removed for servicing and warranty issues which instantIy reverts the car back to standard without Ieaving a trace.

•Adaptiv-SCAN™ Fuel Delivery Software
•Automatic Calibration
•Automatic Voltage Control
•Automotive Quality Components
•Cold Start Delay
•Customer Adjustability
•DPF and FAP compatible
•Driver Characteristic Monitoring™ (New)
•Engine and Drivetrain Warranty Included
•Infinitely Variable Fuel Mapping™ (New)
•LED Function Display
•Robotic Made Circuitry
•Rpm & Load Detection
•Sports mode
•Chip Exchange™ For easy transfer between cars (New)
•VSPP™ (Voltage Spike & Polarity Protection)

Spider® - Adaptiv-SCAN™ Fuel Delivery Software.

Here at Spider® we are very proud of our AdaptivScan™ software.

Not only does it give you the most accurate adjustments to your car's fueIling, but it also has the unique abilty to adapt to suit how you drive your car, constantly. AIl the time the Spider® is installed, it is monitoring and adjusting to suit how you are driving at a rate of 20,000 times per second. So where ordinary "tuning boxes" increase fuelIing on a percentage value, the Spider® will increase the fuelling only when it is demanded and at a rate which is dependent on how you are driving. So, no black smoke beIlowing from the rear of your car like the "tuning box", just clean, crisp and precise performance tuning.

If you like to drive your car hard, then you wiIl not have to wait for the Spider® to adjust, Power on demand™ will kick in maximum power within 0.1 seconds. Monitoring the Ioad value of the car's engine allows the Spider® to know exactly when you want max Power.

Spider® - Automatic Calibration.

Automatic Calibration is a programming feature of the Spider®.

On first instaIlation, the engine is started and left on idle for 60 seconds. During this time the Spider® wiIl monitor and automatically caIibrate itself to suit your individual engine for a complete custom instaIlation. This means that the unit is now programmed for your car aIone. The caIibration procedure only has to be done the very first time you fit to your car. You can then remove the Spider® and refit it without the need to perform the procedure again.

Should you transfer the unit to your next car, the Spider® will automatically perform the calibration procedure again.

[monkeyhanger]

Well I asked a few questions, and they were answered. Their system only modifies the car when needed (“on-demand”), with a 0.1s response time to full power, leaving the car running at normal VW set parameters most of the time. This means that there are no mpg gains to be had, but they stated that most, if not all competitors, state false high indicated mpg values as gains. I have seen this on my system – the higher the performance setting, the higher the indicated mpg I see on my MFD. They also claim that others can have a louder, less regular idle when running at a consistently higher fuel supply pressure because the engine is getting more fuel than it ideally wants at no load. I did comment to my dad when we took the old TDI-tuning box off his MK5 for trade-in that his car was idling more smoothly without the box, but it’s not something I’ve noticed on the MK7.

I’m about to have a few box-free days with normal full-fat diesel and see if I can live without the extra performance. If I can’t then I can see myself sending back the tweaked TDI-tuning box and getting one of these instead.

[AMarsh]

Thanks for the information.

I think I was being a bit harsh last night.  The car is a terrific place to sit, handles great and looks the part.  I think like everyone else, I was sold on the huge mpg figures combined with the hot hatch"esque" performance.  The car is perfectly quick enough in all situations, but because it is so refined it doesn't feel it, well at least in my eyes.  If I was getting 55 to 60 mpg though, I'd be happy with the perceived power shortage, as the diesel compromise would be fulfilling that side of the bargain.   

The new box information you have posted looks interesting, in fact exactly what I am looking for; a bit more oomph and if continued with 45mpg it would suit me to a tee.  I note however there is no claims of being able to connect disconnect in 5 minutes.  Is this a more complicated job than the tdi tuning box?

[monkeyhanger]

AMarsh:

It looks no more complex - a box which connects to a wiring harness, which then connects in to the common rail (and maybe the boost sensor if it is dual channel). In the original email, I asked whether it was dual channel or single channel. The lass (sarah) said both versions were available. The biggest difference once connected seems to be you leaving it idling for a minute for the box to have a learning spell.

I emailed back saying I didn't see on the website that both were available, so do you just ask at the point of ordering. I also asked whether they both had the same output. Didn't get a response before I went home - will check back tomorrow.

Not sure whether Buddy will confirm, but when decelerating to idling, on top setting with the TDI-tuning.co.uk box, there is a bit of a flutter before it settles to 800rpm.

I felt exactly like you did about the car. It wipes the floor with my Scirocco in every way but looks and performance (or perceived performance) - the urgency when you put your foot down is lost in the refinement on the GTD, and on V-power at least, my standard GTD is definitely slower than my Scirocco not running V-power. I do feel robbed that I can't get 50mpg around the doors and 55mpg on a longer run. Hopefully that's down to the use of "semi-skimmed" Shell V-power. I will have my answer over the next day or 2 when I fill up tomorrow.

[Bruce]

I do wonder about some of these boxes that claim to do so much with just fuel pressure signal. If you take the single channel version; all the box has access to is the supply voltage to the sensor (12v ECU provided) and the voltage from the sensor i.e 0-5v which it modifies. How load, rpm and "driving characteristic" can be determined is unknown. The dual channel systems add the potential for a crude load reference.
On a separate note, I love the car with the tdi-tuning box on. Managed a calculated 48 mpg vs 57 indicated on max setting over first 480 miles. Mostly motorway. Going to do some performance tests when i get the chance.

[monkeyhanger]

I do wonder about some of these boxes that claim to do so much with just fuel pressure signal. If you take the single channel version; all the box has access to is the supply voltage to the sensor (12v ECU provided) and the voltage from the sensor i.e 0-5v which it modifies. How load, rpm and "driving characteristic" can be determined is unknown. The dual channel systems add the potential for a crude load reference.
On a separate note, I love the car with the tdi-tuning box on. Managed a calculated 48 mpg vs 57 indicated on max setting over first 480 miles. Mostly motorway. Going to do some performance tests when i get the chance.

Hadn't realised you'd now got yours, glad you're enjoying it. They definitely curtailed mine when it was sent back for tweaks. My level 7 feels like the old level 4 before they made changes. If they stopped trying to sell these on false indicated mpg gains then there'd be less disappointment, now I just feel a bit shortchanged by them cutting the power down to supposedly get me more mpg (which hasn't worked, and I didn't think it would). 48mpg vs 57 is a whopping 19% over-optimistic. I reckon you've been having a LOT of fun with the car for the discrepancy to open up like that (mine is about 15% on level 7).

The "Spider" system does seem safer for the car (on paper), by not putting the common rail under extra pressure all of the time, falling back on normal when there isn't much demand on the car. Do you know how much extra pressure we're talking about on the modified signal with these boxes to force through 15-20% more fuel on any given throttle response? I personally haven't a clue without going through the physics for it that I haven't touched since my uni days.

Maybe that Spider box measures the rate of change of those "normal" signals and decides whether it's enough to kick in the big signal changes that get more fuel pressure through the common rail or whether to leave the car alone on stock signals?

[monkeyhanger]

I officially asked to send back my TDI-tuning box this morning, via email – not heard a peep from them. Will give them until the end of the day and then I’ll ring. Asked my mate to send an email enquiring about getting one for his Audi A4 and email responded to in about 90 seconds.