Turbo Lag Proven

Discussion in 'Gran Turismo 5' started by Lock2Lock, Aug 9, 2013.

  1. 4everdelayed


    While those things are usually correlated, they're not the same thing. You can have a huge turbine for high boost pressures and still have low lag (because of exceptionally light components). You can have a small turbo with very low boost and still have ridiculous lag (because the turbine weighs so much).
  2. Ridox2JZGTE



    True, those things exist on some turbo kits in GT5, you can't just put a turbo on any car, just like in real life, some turbo won't match to the recipient engine. GT5 also simulate twin turbo, single and twincharging system. Each car turbo upgrade kits are not the same to another car upgrade kits, even if they are the same rpm range type, there are variety of boost pressure, compressor size ( power ), effective rpm and some of them have the boost drop off on high rpm - of course I can make it keep on full boost until red line :lol:
  3. bread82


    Whoa, lots of debate here!

    My 0.02:

    The way I have always heard turbo lag described is the throttle response description that has already been mentioned above (and so far I've not seen any evidence of this occurring in GT5, but I'm open to other peoples' evidence).

    The best way to test this in my opinion is as follows...

    You will need:
    1) A stopwatch (or the in-game timer)
    2) A car with a turbo. Probably best if it's a Stage 3, since in real life a big turbo would be expected to exhibit lag more than a small one.

    To avoid any confusion of boost threshold or how boost varies with RPM above the threshold, make the starting point for the test at the max torque rpm. This will be well above the boost threshold.

    Get on SSRX, and get up to a reasonably long gear (4th?) so you won't get wheelspin or max possible car speed limiting the test.

    Say your peak Tq is at 4000 rpm.

    A) Change up to 4th well below this (you can even do a standing start in 4th if you want). Keep the throttle floored, the turbo should eventually be spinning up happily. When you cross 4000 rpm, start the timer. Keeping the throttle floored, stop the timer when the revs reach , say 5000 rpm. Ideally you want the 4000-5000 rpm sweep to take 5-10 seconds to stop human timing error from pressing the stopwatch button being a major influence. Change gear ratios if necessary until you get a decent time period to test.

    B) Repeat the test, but instead start at redline in 4th. Close the throttle. You can even start in 5th and then change down to 4th when the speed allows. With the throttle closed, let the car roll, the revs will drop. When the tacho falls to 4000 rpm, stamp the throttle all the way open and start the timer. Stop timing at 5000 rpm as before.

    Best to do 3 repeats of each test and take the averages, just to be thorough.

    You've just compared the same rev ranges, in the same gear. The only difference is whether the throttle has just been blasted open from being closed (turbo spinning slowly initially, and would have to spin up), or whether it has always been open (turbo initially spinning at full whack)

    I've not noticed any difference i.e. lag using this method in GT5.

    I think some of the debate above has been caused by the rpm delay between boost threshold and max possible boost. I'm not at all arguing with this observation, it's just not what I've come across when I've heard the term "turbo lag".

    Without the "throttle response" turbo lag being in GT5, the different stage turbos (in my opinion) just act like a cam timing change (powerband moves), coupled with an increase in compression ratio (more power overall), i.e. NA tuning!

    It's a shame the "actual" GT5 NA tuning doesn't allow reshaping of the powerband :-(


  4. Imari


    Very good stuff. This is the way to test it.
  5. Johnnypenso

    Johnnypenso Premium

    The idea is good, but there is no way given the limitations of GT5's tach display and a stopwatch, you can be anywhere near accurate enough to measure the tenths of a second needed to determine this.
  6. Ridox2JZGTE


    Boost gauge in GT5 is deadly misleading, take the Supra MA70 Turbo A for example, look at the left portion of the dash, there's a boost gauge there, now install high rpm turbo kit, look and compare both boost gauges - HUD and on the dash, no relation at all, more boost from the turbo - hint - listen to the spooling sound, and the displayed boost gauge are both wrong :D The dash will show stock turbo boost level, and the HUD will have different boost indication than what the sound of the turbo suggests. This also happens with some other cars which has boost gauge in cockpit - S15, R33 GTR and some others.

    I installed a different turbo high rpm kit than the original kit on my Group A MA70 Supra replica, increase the boost to max that holds until red line, alter the rpm torque peak output at low 3200rpm with high rpm kit :D and sports exhaust, boost started from as low as 2500rpm, both gauges are not accurate. Need to listen, and feel the engine revving. She's hauling from low rpm like a freight train with rocket booster :lol:
    Last edited: Aug 12, 2013
  7. R34EVO9

    R34EVO9 (Banned)

    United States
    All I have to say is you cant experience turbo lag properly in gt5 and its kinda random when it happens but it's usually under full throtttle in 2 or 3rd gear never really first. And its best to use something like a evo or the mines r34 those cars are known for the'relag
  8. MOTORTRENDmitch


    Nice job and all, but I didn't know there was any doubt of GT5 having T-Lag. Anyone with a brain should be able to tell, "my car with a huge turbo doesn't seem to have the steam it usually has when I'm at 3,000 rpm."

    Haha, anyway, good job. ;)
  9. GTP_CargoRatt


    United States
    It has been a rather educating thread, tho heated at times. I hope everyone can still be friends after this. :lol:
  10. Exorcet

    Exorcet Premium

    And then you have the 505 cubic inch NA V-10 of the 03 Viper SRT-10 doing the same thing (in GT5). And that's turbo lag?

    It has nothing to do with RPM or the powerband, but people have insisted it has since time began, and there will probably be another one of these threads for GT6 whether or not lag is finally modeled. Actually, I kind of wonder what will happen when GT does get lag. Maybe people will call it a glitch.
  11. BongRipz


    United States
    Is it expected to be properly simulated in GT6 finally? :cool:
  12. Exorcet

    Exorcet Premium

    From what I can tell, there is no reason to expect lag in GT6, but it's too early to be sure.
  13. 2_FAST_4_U


    United States
    Remember in GT4 winning the cool looking Option Stream Z and thinking wow only to find out about the big turbo lag and power loss ?
    In GT5-Turbo Lag problem solved For Nissan OPTION Stream Z '04 simply by using the Garage Editor. Here is the how to...

    1) Ticket Only In GE - Nissan 350Z Concept LM Race Car and deliver in game.
    2) Do Car Wash, Oil Change, And All Mods in "A" Setting only and then copy A over to the B And C settings.
    Note: For extra special parts get the racing super soft tires only as some other specials allowed can create problems.
    3) Save game on USB, open it in garage editor, and correct any hex codes and tune sheets as shown below for A-B-C settings.
    Note: The Body, Chassis, and 282_285 codes changes shown are mandatory !
    Rename in GE - OPTION Stream Z '04 Hybrid or whatever.

    When complete you'll have A-B-C setup with zero turbo lag as follows:
    A = 800+HP
    B = 1,000+HP
    C = 1,400+HP

    Nissan OPTION Setting A-1.JPG Nissan OPTION Setting A-2.JPG Nissan OPTION Setting A-3.JPG Nissan OPTION Setting A-4.JPG Nissan OPTION Setting B-1.JPG Nissan OPTION Setting B-2.JPG Nissan OPTION Setting B-3.JPG Nissan OPTION Setting B-4.JPG Nissan OPTION Setting C-1.JPG Nissan OPTION Setting C-2.JPG Nissan OPTION Setting C-3.JPG Nissan OPTION Setting C-4.JPG Nissan OPTION Tune Sheet A.JPG Nissan OPTION Tune Sheet B.JPG Nissan OPTION Tune Sheet C.JPG

    Nissan OPTION Stream Z '04 Stock (Standard)-At Circuit de Spa Francorchamps 5.jpg