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The value of Re-Mapping Diesal Engine Cars

Discussion in 'Motors' started by Curiosityx, 1 Aug 2006.

  1. Curiosityx

    Mobster

    Joined: 17 Oct 2002

    Posts: 3,941

    Location: West Midlands

    Greetings, ive been aware of the ability to re-map the Ecu on most cars for along time now.

    Ive currently got a new Vauxhall Astra 1.7CDTi and have recently been considering having it done to take it from 100Bhp to 130Bhp.

    Im aware that this could invalidate my warrenty but does anyone have any personal experience with trying this on a diesal engine car and are there any pitfalls to the process?

    Regards,
     
  2. Bug One

    Capodecina

    Joined: 18 Oct 2002

    Posts: 10,807

    Location: Sandwich, Kent

    Well, without actually ever owning a diesel, I would say that the benefit will be increased power and the pitfalls will be probably

    - Poorer mpg
    - More stresses on the engine, gearbox, clutch which theoretically would decrease their lifespan
    - Possibly reduced resale value?
    - Increased insurance premiums (if you declared them).

    IMO the whole point of buying a diesel is to reduce the cost of motoring, so I really dont see the point. However I'm sure others will quite rightly disagree.
     
  3. paradigm

    Caporegime

    Joined: 26 Aug 2003

    Posts: 36,729

    Location: Staffordshire

    Re-maps do not necessarily reduce MPG. Infact in many cases MPG can be unnafected or even go up!
     
  4. austinpowers

    Wise Guy

    Joined: 29 Sep 2003

    Posts: 2,435

    I tried a remap to replace my tuning box.(which i kept as the remap didn't justify the cost small increase in perfomance and cost, over the existing box)

    The remap how ever made a great deal of difference below 2k.

    Wear and tear should be minimal, but that depends on the tolerences built into the engine and drivetrain, i fitted a PSI tuning box to my Astra 1.7DTI (which i had from 5 miles) @ 40k and it was still on it's original clutch when the turbo died @ 139k, i never used to hang around and carried alot of weight in the car :)
     
  5. [TW]Fox

    Man of Honour

    Joined: 17 Oct 2002

    Posts: 157,261

    The point is that the 100bhp 1.7DTi engine is so mind numbingly horrifically slow that anything you can do to relieve the tedium is a good idea.
     
  6. Jonners

    Capodecina

    Joined: 22 Nov 2002

    Posts: 17,679

    Location: Wherever I want to be

    Why didn't you buy the 1.9CDTi 120ps and get it tuned to 180-190bhp?
     
  7. [TW]Fox

    Man of Honour

    Joined: 17 Oct 2002

    Posts: 157,261

    'omg my monthly payment...' probably.
     
  8. Jonners

    Capodecina

    Joined: 22 Nov 2002

    Posts: 17,679

    Location: Wherever I want to be


    :p
     
  9. Oracle

    Banned

    Joined: 17 Jan 2006

    Posts: 1,971

    Location: Haskins

    Chipping Diesels is common place and an everyday occurance.

    There are two options that do the same thing, but really they shouldnt be done together. Thats not to say it wont work or be of benefit, but it is adviseable to be carfeful.

    Here is the list:-

    Primarily, Diesels respond to tuning in the same way petrols do, but with just greater gains (due to having a turbo and large torque as standard).

    A remap will tailor tune your car to a specific set of parameters. It will take into account air/fuel ratio, boost pressure (if controlled electronically), increase fuelling at certain points to produce more bhp and higher torque, and remove any flat spots. This will actually probably improve mpg as you'll find you do not need to change gear as much and you can pootle around town in a higher gear (i go everywhere in 4th in town (30mph) and can still pull away quick if I need too)). Therefore, mpg will be unaffected or improve slightly.

    A 'chip' is just that. It piggybacks either to the ECU or sits seperately and dumps more fuel into the engine. Whilst this has a good overall effect and increases bhp and torque it can affect mpg more than a remap although the gearing theory still applies.

    I have a chip (MG ZT 135+ CDTi) that doesnt just increase fuelling. It also analyses real time airflow data and matches fuel accordingly. This works very well and has adjustable settings. I am unaware if such a chip exists for the GM range.

    Here though a chip does not always alter turbo parameters and you will notice significantly more 'smoke' out of the back of the car. Whilst embarrasing, this can be 'reduced' by increasing boost on the turbo by a few PSi effectively turning that smoke into more power! You'll have to check if your turbo can be adjusted manually or if it can be controlled by an Electronic Boost Controller.

    Lastly, other simple things like airfilters and exhausts also help diesels breathe better, run smoother and gain bhp and torque.

    A chip can always be removed (normally completely without trace) should any problems occur and the car needs to visit a dealer. A remap cannot be removed without a ECU FLASH and the dealer is likely to spot this.

    I am aware of someone who has both remapped and chipped thier diesel. Even they do not recommend this if you are suspect to temptation as you are likely to cause damage over time.

    HTH, thats as much info as I think you really need.
     
  10. Vertigo1

    Capodecina

    Joined: 28 Dec 2003

    Posts: 15,396

    And yet he was only 10ish seconds off my 'ring lap time in the A3!

    I'm so crap :(
     
  11. [TW]Fox

    Man of Honour

    Joined: 17 Oct 2002

    Posts: 157,261

    He has exceptional talent, dont feel so hard done by :p
     
  12. Oracle

    Banned

    Joined: 17 Jan 2006

    Posts: 1,971

    Location: Haskins

    LOL! But in fairness 10 seconds considering the top speed down the last straight is massive!
     
  13. Vertigo1

    Capodecina

    Joined: 28 Dec 2003

    Posts: 15,396

    Well that would be a factor except that these are BTG (Bridge To Gantry) times, which is all you can do on public days, and the gantry "finish line" is pretty much at the start of the final straight.

    Actually his time is even more impressive when you realise how much the huge hill leading up to Karussel takes out of a 100bhp diesel. I reckon that hill is where I made virtually all of that 10s advantage as, on the couple of occasions that I followed him round, I could only just stay with him!

    As another measure of his god-like driving abilities, in the 190bhp Rover he was only 20s off Tom's time in the M5!
     
  14. schnipps

    Soldato

    Joined: 18 Oct 2002

    Posts: 5,381


    An extra 70bhp from a remap alone?

    Seriously i doubt that.

    I am getting mine remapped (Revo'd) in a few weeks which will take it from 150 to 190 and up the torque to 290. The VAG diesels respond really well to remaps and as for the mpg comments its well known they dont make it any worse, if anything its slightly better, also companies like Revo invest heavily in R+D for remaps and so no it wont put excess stress on the car at the setting they provide.

    You could got for a custom map and take the 150 lump over 200bhp, i think 220 is achievable but then you are getting into clutch problems etc, 190 from the 150 is not going to stress the car.

    Also it wont effect residuals as you can disable it via SPS and as for warranty its unlikely they would notice as its undetectable and can be disabled, even SEAT themselves said when i bought my car they dont mind remaps and actually even provide a remap service at a main dealer.

    Ans no people dont JUST buy diesels for economy, thats a part of it but some also like the power delivery, there is nothing wrong atall with wantinbg to get an extra chunk of bhp if its just sitting there waiting to be "unlocked".
     
  15. austinpowers

    Wise Guy

    Joined: 29 Sep 2003

    Posts: 2,435

    Stop de-railing this thread :rolleyes: :rolleyes:






    :p :p

    I'm not that good honest...
     
  16. Vertigo1

    Capodecina

    Joined: 28 Dec 2003

    Posts: 15,396

    Before your head doesn't fit through the door? :D
     
  17. austinpowers

    Wise Guy

    Joined: 29 Sep 2003

    Posts: 2,435

    Or my belly, now where's my lager :p
     
  18. Demon

    Soldato

    Joined: 22 Oct 2002

    Posts: 7,123

    Location: Near Cheltenham

    The VX CDTi 150 can be taken to 200BHP/330lbft with the semi official VXR Remap. ( I think it's a genuine 195BHP/315-320lbft)

    I've had my Zaffy done, and the difference is well worth it, fuel consumption hasn't altered, although I do tend to use the performance more often.

    Its switchable on the fly using the 'sport' switch, good for re-affirming the difference when you get used to it

    The engines are quite strong, as they will be using the same engine/box in the 212BHP Sequential turbo next year..
     
  19. Curiosityx

    Mobster

    Joined: 17 Oct 2002

    Posts: 3,941

    Location: West Midlands

    Because initially it was a company car and that choice was limited, it also have £3.5k knocked off the price as it was a demo with very low mileage.

    I thinks it a fantastic motor and is nippy the way i drive it but would like to make it a little sweeter.

    If i had my choice i would of had an A3 2.0 TDI Sportline.


    Thats a fantastic response, cheers!

    :)
     
  20. Defcon5

    Soldato

    Joined: 4 Sep 2005

    Posts: 6,424

    Location: Whitwood, West Yorks

    If doing this makes the engine use more fuel how can it not alter mpg?

    (forgive my noobness)