Are you thinking of buying a DTUK tuning box?

**midgster** · 3rd March 2011, 17:25

If so, just do it! You won't regret it.

I have had a Vectra Sri 150 for about 6 month now and absolutely love it. Having been toying with the idea of a DTUK tuning box for some time, but couldn't really justify the £300 odd for it, considering the car was pretty quick already. To be honest it was mainly the better fuel consumption I was more interested in as I do 40,000 miles per year, mostly motorway.

Anyway, I spotted an ECO3 box on Ebay last week currently at about £30, listed by someone with zero feedback and it was due to end at an unearthly hour in the morning (about 3:30am) - common noobie Ebayer mistake.

So I thought I'd have a punt at it, set up a quicksnipe for £100 and crossed my fingers.

Following morning check my Ebay and I had won it for £46!!!!

Priot to it arriving, I did a few days trial runs, resetting on the onboard computer to find out what mpg I got on my journey to work (54 miles, 50 on the motorway). So with the cruise set at 70mph I got 52.3 and 52.5mpg on the 2 days.

The tuning box then arrived, plugged it in which took 2 mins and off I went. I drove exactly as I had the past few days, somehow managing to resist hoofing it to see what the performance gains were like.

Arrived at work and check the trip computer and couldn't believe what I was seeing........

66mpg!!!!!

Then, for the way home , thought I'd check out any performance increase.

HOLY SWEET MOTHER OF :CENSORED:

I can't believe the difference. It pulls from 50 to "cough" mph in no time at all.

To top it off, today on the way home, I had the pleasure of a 52 plate M3 comin right up my backside. Once the car in front pulled over, I accelerated just a little to overtake the car in front, then pulled into the middle lane to let the M3 pass, or so he thought LOL, as he tried to overtake, I'd dropped 2 cogs from 6th to 4th in readyness, and no word of a lie we were neck and neck until I thought about my license, so then let him passed.

I'm sure from 100mph+ the M3 would leave me behind but for everyday speeds, I can't belive my Vectra Diesel was giving an M3 proper grief.

I felt well chuffed.

Can only imagine what the M3 driver was thinking

So, the morale of the story is....

BUY A DTUK TUNING BOX...YOU WON'T REGRET IT

**bangty 1** · 3rd March 2011, 17:38

dtuk lieto the computer so that 66 is wrong

**midgster** · 3rd March 2011, 18:10

Well, on a full tank the computer used to say Range = approx 650 miles, so I used to get around 600 miles before refueling (not going into the red). I have currently done 670 miles and still not that close to the red. Computer currently says range of 96 miles, so a total range of 770 miles. An increase of approx 20%, pretty consistant with 52mpg to 66mpg.

This ties up pretty accurately with the odometer, so it seems to be telling me the truth!

**bangty 1** · 3rd March 2011, 18:16

well i say its not sorry to say and i bet a few others will say the same thing to i had a dtuk box and it push more fuel in to the rail so i cant see it saveing you fuel maybe wrong but id say im right but these boxs do make the computer lie trust me

**midgster** · 3rd March 2011, 18:28

But surely they can't lie to the odometer can they? As that is showing a 20% improvement.

**cont1204** · 3rd March 2011, 18:38

Best way to work it out dude is to do a full tank of diesel with the box off, then a full tank with it on and see from that. Most accurate way. The increased economy comes from not having to work the engine as hard. The trip computer will be slightly out now though because the ECU thinks it's injecting a certain amount of fuel but the box is fooling it and injecting more, that's simply how they work.

Now you're boxed, work it out from a full tank and see, best way to do it! Enjoy the power

**bangty 1** · 3rd March 2011, 18:39

no put its like a suger pill thing have to thing just driveing diffrent for one day racks the miles up i can stick £20 in it drive all week then next week only last 3 days driveing the same or so i think but im not as iv used a weeks diesel in 3days...........i had a dtuk box still have and i was reading 70mpg sometimes which i know is wrong and loads of people on here have sed the boxes lie to computer but i would not belive it mate really i wouldnt.............is it a dtuk 3 box?? what number you have it on??

**byebyeitsagsi** · 3rd March 2011, 19:02

As has been said its fooling you, the box makes the car over fuel which fools the car into thinking its using less. Work it out manually to get the true mpg.

**midgster** · 3rd March 2011, 19:12

OK, I understand the trip computer may be tricking me, but the odometer isn't!

Before the box I would get 600 miles before filling up (still with maybe a gallon left)

My current odometer reading (not the computer!) is currently reading 670 miles, and I still have more fuel left than when I normally fill up. I'm guessing another 50 miles before I will fill up.

Ergo, pre box = 600 miles between fillup
post box fitted = 720 miles between fillup

Again this is being measured by the odometer and not the computer.

I know some people will say that I am just driving differently, but as explained earlier, I do the same trip every day, in pretty much exactly the same econmical manner ie to save fuel, always have done, always will do.

My journey:
Leave home. 2 miles urban driving (no traffic jams) to the M3, 50 miles on M3 with cruise set to 70mph, and then 2 miles urban driving (again no traffic jams) to office.

For the last 6 months, 600 miles to a tank pre DTUK box every time (give or take a few miles). First tank after box = 720 miles.

And actually when you think about it, I've actually booted it a few more times than usual too due to the extra power.

Of course, I will need a few more tankfuls of testing to be absolutely sure.

I just want to reiterate, that I am going by the odometer reading , not the computer.