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More power from my 1.9TDi 150 leon cupra??

Discussion in 'TDi Tuning' started by CupraDerv-chris, Oct 5, 2009.

  1. slick

    slick Bit of an animal

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    Ok well taking in that account then Alex, how far can the SOI be advanced to in the ECU and well the PD engine i would say revs to 4500rpm given its rev range on the ARL/ASZ/BPX 8v engine...
    Then the question comes to what is the limit of pressure a OE headgasket can take and the cylinder peak pressure limit, given those two limits what would the bhp and torque be limited to?

    Then we can look at if the headgasket and cylinder was to be reinforced, what advantages there would be on this, over say normal route, as in the TDI forums i have never seen a meation on cylinder pressures and head gaskets be a problem on some of the most powerful TDIs in the US, pulling huge numbers over there with race injectors and modified cams and retro fitted turbos. There is alot of talk on oil temperature and pressures to the turbo etc, but nothing of meation of head gaskets or cylinder limited pressures?
    If you could explain/expand on you meation of these, it would let us all understand better your thoughts of why they dyno graphs and company claims of power, and also question them when they boast they can modify the TDI to such levels?
     
  2. brad1

    brad1 Guest

    Its the same with both majesty and chispadete, they have nothing better to do than sit on a pc all day and think they are right when clearly wrong. Let them sit there all day working out incorrect stuff, we all know standard injectors can produce 260bhp, jonjay has proven this on a reliable dyno with 257bhp ;)
     
  3. brad1

    brad1 Guest

    Tom, you also say that its very unlikely that strugers1 made 242, didnt ash make 240 at rs tuning, so we all know that 240-260bhp is very achievable ;)
     
  4. majesty78

    majesty78 Active Member

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    :lol::lol::lol: LMAO....

    How should i discuss with someone who shows NONE knowledge about what he tries to talk about....

    I ask you once more: Explain me how to do it, and i will be the first to try it...

    Your problem will be: You cant explain.....

    And if you look how often i write on here, you should see that i am not online very much, mate (I guess you´re happy about that...)

    Your behavior is absolutly typical: getting personal when technical knowledge reaches its limit...
     
    #44 majesty78, Oct 18, 2009
    Last edited: Oct 18, 2009
  5. majesty78

    majesty78 Active Member

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    The SOI is kind of critical if you start pulling it in the "earlier" direction.

    As an exapmle compare ARL and BPX engine. They only differ 10bhp, but if you look at the power curve, the BPX engine has its max. power @ 3750 revs, the ARL @ 4000.

    This has some reasons, like combustion efficiency, BMEP, cylinder pressure and so on.

    The OEM surtanly has to develope to meet the 250.000km specification, so there is room to change mappings and raise those parameters.

    As a rule of thumb you can calculate 2mg/stroke for every degree of duration in the most effective combustion/injection window with stock 550cc nozzles. (By the way the 550cc nozzles flow 55mg in OEM calculated best injection window, 520 cc nozzles 52mg and 465 do 46.5mg....)

    Like stated before, in ARL engine the OEM starts injection at 23.5 BTDC and ends 4 degrees PTDC to reach 55mg/stroke, in tuning conditions I know of some using 26.5-27 degrees SOI and 6-8 degrees end of injection.
    BUT: If you try it on a dyno/track or any other way to compare real power gain, you will see, that injecting past 5-6 degrees does almost nothing for power anymore, it just makes sound and warm air...(there are several professional tuners i know who will confirm that out of their own track/dyno testings and expierience). There is a LITTLE gain when you go further than 6 degrees, but in relation to the injeted more quantity the power gain is to little.
    Then there is another point to mention: ignition delay. This parameter describes the delay of ignition with raising rev numbers, it s a physical effect, when combustion happens it needs a surtain time to burn up fuel. The diesel fuel is actually slow burning and so this effect is stronger in a TDI than i a gasoline engine.
    Calculate 0.1sec for that, which makes 2 degrees of delay @ 4000revs.
    With raising revs this delay gets more and more overproportional.
    This you must calculate with when setting up mapping.

    So, even if you set SOI at 27 degrees and let it end at 6 degrees you have 33 degrees of duration, and as an result from that you have "only" a bit more than THEORETICAL 66mg/stroke what creates 370Nm/272lbs/ft at the best operating point. But in practic you already loose efficiency, so there will be max. 355-360Nm

    (Now i would like to know how to gain almost 200Nm from 310 up to 500 like has been shown on here already???? You would need 46degrees/92mg for that*g*)

    However, know lets say we can create 360Nm @ 4000revs

    With the correct amount of airmass/boost you would see 205hp with that torque @ 4000revs.

    BUT:

    These 33 degrees are IMHO no option for a mapping what I would sell to a normal customer who wants to drive 10min WOT on highway.

    So then, if climbing higher in rev band there are some issues showing up, first is the above mentioned ignition delay and as a second you need more and more airmass to get an acceptable lambda and EGT.

    So lets look to the lambda first: OEM calculates about 18-19:1 for a smokefree mapping, if you dont mind a little grey haze take 17:1 which makes a 1,15:1 AFR.

    To hold up this AFR you need at least 1,8bar of boost @4500revs, clearly we dont have to talk about doing this with a stock turbo, but even with one of those hybrids you wont do that durable. Take a look at a compressor map from an 56mm compressor in a therefor made 56mm housing, at a pressure ratio from 2,8 and over 22lbs/min flow this will be critical even for this compressor. BUT (again) the Hybrids work with 56mm wheel in a GT1749 compressor housing. Take a OEM 56mm housing in your hands and compare it to one of those hybrid housings. You will see the 1" outlet on the hybrid housing and almost twice outlet diameter on the OEM 56mm housing. And a different A/R of both housings.

    Now take a guess which of those housings will flow better....

    The consequence out of that: You cant hold up full injection quantity when revving higher because the car would start to smoke, raise EGT and so on...So there is no way to make 230-240-250-260 hp. Not with stock nozzles and not with an hybrid like a gt1752 or 1856...


    To your question concerning PCP and BMEP: The bad thing about that is, that no one measured this before, all you can have and will find are more or less educated guesses...

    Regards, Alex
     
  6. brad1

    brad1 Guest

    No one is going to listen to you saying you can get this much power when all these tuners are getting 220bhp-260bhp out of standard injectors, my point is instead of coming on here throwing all these incorrect (well correct calculations in your opinion) calculations about moaning too customers, why don't you phone up these companies and explain to them, maybe cause you will know you won't get anywhere ;) if your so good at all this stuff, why not set up your own tuning company then??
     
  7. majesty78

    majesty78 Active Member

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    Well, i dont bother if people have fun getting ripped of. They are welcome believing in their favorite tuner, i´m ok with that.

    I am just explaining it in technical why those numbers are not plausible. If you, or any other user here is not willing to believe in it, then i am also ok with that, i will sleep fine anyway, everybody has its own opinion.

    Some have it from their tuners or forums, and other have it elsewhere like R+D for example.

    BTW it is also a well known fact that a stock PD head wont flow the required airmass for over 230hp, at this point air velocity gets so high, it comes to instable flow caused by sonic speed what is reached in sertain areas in the cylinder head.
    But for knowing that you should have seen this on a flowbench....

    This is just another proof for unplausible numbers...

    Why should i phone up these companys? Its their business, not mine, and i am not the one who wants to change their philosophy how to sell their products. I guess they read this here anyway, and how many of them chimed in?

    Oh, and maybe i have a tuning company in background which you dont know about???


    Regards, Alex
     
  8. Tom.

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    I didnt say 240bhp isnt achievable. Thats about the most you will get, and it will be VERY smokey.
    What i said was, that with the amount of torque struggers had, im very doubtful that it produced a genuine 240bhp. Bhp and torque come hand in hand.
     
  9. majesty78

    majesty78 Active Member

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    Brad1, you seem to have enough knowledge to call my posts wrong.

    So please, share you knowledge with this forums and show us how to calculate correctly, I am sure all interessted users will be happy to read about it how it is done in the right way.

    I´ll be waiting.....

    If no one is listening to me, so then maybe everyone is listening to your wisdom.....
     
    #49 majesty78, Oct 18, 2009
    Last edited: Oct 18, 2009
  10. jonjay

    jonjay 50 Years of 911

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    Thank you for your postings Majesty at least what you said points us all in the right directions in terms of understanding where you are coming from. I have refrained from posting on here because saying I have 257bhp and my car is faster than your car doesnt interest me.

    What sort of logs will I need to run to see what the car is doing? I will do my best to get these up in the coming weeks.

    Block 4 and 11?
     
  11. majesty78

    majesty78 Active Member

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    If you like, you can make Logs from Block 4, 8 and 11.

    But just to mention, I am not going to post up any DIRECT critics againt a company which is registered on here.

    If you want to we can handle this via email....

    Make those logs in 4th gear from 1500 (or lower) to the redline you respect. But do these logs seperatly, not all 3 together!

    REgards, Alex
     
  12. majesty78

    majesty78 Active Member

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    Reminder #1 to brad1....
     
  13. devonmikeyboy

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    Sorry Brad1 but you are out of line. majesty78 knows more about turbos and diesel tuning then anyone on this site by a long way. I am not saying he is right or wrong on this or any other subject but you need to show him some respect for the knowledge that he has and gives to this site. He has a right to a opinion and to say what he thinks like everyone else on this site. Do you even understand his quoted calculations ? Phoning a tuning company and saying they are wrong etc is a waste of time, nobody in their right mind would bother wasting their`s or the tuning companies time doing so.
     
  14. majesty78

    majesty78 Active Member

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    Mike are you ok? Shall i call you a doctor?*g**g**g*
     
  15. Andrewcupra TDI

    Andrewcupra TDI Resident Desk Jockey

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    bumping the topic along , am interested to see the outcomes jonjay ,
    how much £ are the race injectors , i had a search before but was from different countries etc
     
  16. deanomite

    deanomite Active Member

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    BHP claims

    Going back to all the interesting technical stuff, I have some questions for you all.
    My car is an 05 cupra 1.9 tdi. It has a stage 2 TD turbo, Sachs clutch and a decat otherwise stock.

    It was set up at RS and made 241bhp and 360ft lb, the car after me was a lovely BMW 123 which made 204bhp totally stock which is what BMW claim.

    I did a track day at Cadwell the following week and passed two 3.2L AUDI A3s on the back straight. They were flat out because i had a chat with them and they couldn't believe the car was a 1.9L tdi :).

    Could some of us be talking wheel bhp and others crank bhp ? Because my car made 202bhp at the wheels

    If it is not possible for the TD turbo to make up to 260bhp aren't TD leaving themselves open to legal action advertising they can?

    If the dyno figures are so far out why did the BMW make the same power as BMW say?

    If the car is not making good power how did it pass the 250bhp A3s on the straight ?

    If the injectors cannot supply enough fuel for that power why does my car smoke so much? I would have thought lots of smoke would mean to much fuel if anything?
     
  17. brad1

    brad1 Guest

    Exactly how i think of the whole situation too mate :)
     
  18. jonjay

    jonjay 50 Years of 911

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    What Alex is saying is that with the information we know specification wise on the injectors, pistons, cam etc..using specifications/calculations given by the manufacturers, VAG and people with technical know how it isnt possible for a such a specification to produce such power.

    Now I havent got the patience today to start saying why it is not possible however having had a very lengthy conversation with Slick who had a lengthy conversation with Alex. I do agree that using the calculations given by Alex it isn't possible.

    HOWEVER this isn't to say the figures I have achieved and others cant be achieved as there are lots of variables to consider.
     
  19. majesty78

    majesty78 Active Member

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    There are indeed a lot of variables to consider.

    For a start, the most misreading failures on dynos appear when having an aggressive tune with a heavy torque kick in, this, combined with the poor engine- rpm readings while the run gives false numbers on almost every wheel-or hub dyno.
    Then, you can/could manipulate any dyno within seconds to show various results even on the same within 5 minutes, i dont say that somebody does so, i just say it is easily possible.

    To the speed thing: Here we have a typical situation which is giving the tdi an big advantage compared to an natural aspirated engine: TORQUE.

    Combined with good matching gear ratios, different aerodynamics, tire size and so on, you will be able to pass by a more hp gasser up to a given speed level.

    But at one point, you will fail: Top speed.

    Because for top speed, all you need is power, power, oh, and power....

    For acceleration up to given speed levels, the torque and the weight of the car is important, but at higher speed regions the aerodynamics and power is important.

    Just to compare: my car per example has 215hp and almost 450nm of torque combined with about 1120kg weight.

    In speed regions up to 160-180kmH i can easy hold up with the Ford Focus ST with remap of a friend of mine. This car has 280hp and 4 think plenty of torque also. But when going up to topspeed, all whats left over to me is to look at his taillights...

    With my 215hp, the car runs 260 on the odo and 248 GPS, adding another 30, 40 or even up to 50hp like stated here, should make the cars even run over 260GPS km/H, as long as the gear ratio of 6th gear allows it...


    To the smoke: smoke is not always a sign of overfueling, if the duration is to long, it will also smoke, combined with high egt and bad treatment to the turbo.
    When the turbo was capable to handle the advertised power levels, the car would not smoke because you would have enough airmass and boost to make a clean tune. Everything else is actually not more than a more or less 'bad compromise'....


    Regards, Alex
     
    #59 majesty78, Oct 25, 2009
    Last edited: Oct 25, 2009
  20. deanomite

    deanomite Active Member

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    Thanks for your replys i wont go around quoting the power any more lol .
    The car is great fun though :D.
    I have a spare cyl ,head does anyone know if there is much to be gained from any work being done to it at this stage ?
     

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