Sport & Sport+ have different boost
#91
Thank you for bumping this thread I was meaning to do it after this past weekend's drive...
I just noticed this in my T - manual with sport chrono. First time I really investigated sport + and boost since I bought the car. 92 degrees outside, 800 ft altitude. In normal and sport mode, the max I could hit was 12 psi. In sport +, I was hitting 13 psi consistently at 5k rpm it was whipping into 14 for a split second on shifts. Also, boost response is WAAAYYYYYYYY better in sport plus. You get 6-10 psi with very little throttle application. I changed my individual mode drivetrain setting to sport plus. Its like you get a free mild tune for the car. This alone is worth the cost of admission for the sport chrono pack if you ask me (even in the manual).
Another thing I found that could be interesting for 991.2 manual owners with sport chrono...
The "poor man's launch control" (depress clutch and floor gas) instantly pins the revs at 4k rpm, but its different between modes. In sport mode when you do this there is 0 boost. In sport plus you get 2-3 psi of boost and the turbos are preloaded for the launch (even though the dash doesnt say "Launch Control Activated" like in the pdk). I havent released the clutch and tested it out yet because I havent found a safe place to do it, but its nice that you have options for the launch. The sport mode launch seems to be easier on the drivetrain (as it was in my Macan Turbo - it pinned the revs at 3500 vs 6000 for sport +). Neither sound as violent as the pdk launch sequence... not even close... the pdk launch control sounds like the engine is eating itself
I just noticed this in my T - manual with sport chrono. First time I really investigated sport + and boost since I bought the car. 92 degrees outside, 800 ft altitude. In normal and sport mode, the max I could hit was 12 psi. In sport +, I was hitting 13 psi consistently at 5k rpm it was whipping into 14 for a split second on shifts. Also, boost response is WAAAYYYYYYYY better in sport plus. You get 6-10 psi with very little throttle application. I changed my individual mode drivetrain setting to sport plus. Its like you get a free mild tune for the car. This alone is worth the cost of admission for the sport chrono pack if you ask me (even in the manual).
Another thing I found that could be interesting for 991.2 manual owners with sport chrono...
The "poor man's launch control" (depress clutch and floor gas) instantly pins the revs at 4k rpm, but its different between modes. In sport mode when you do this there is 0 boost. In sport plus you get 2-3 psi of boost and the turbos are preloaded for the launch (even though the dash doesnt say "Launch Control Activated" like in the pdk). I havent released the clutch and tested it out yet because I havent found a safe place to do it, but its nice that you have options for the launch. The sport mode launch seems to be easier on the drivetrain (as it was in my Macan Turbo - it pinned the revs at 3500 vs 6000 for sport +). Neither sound as violent as the pdk launch sequence... not even close... the pdk launch control sounds like the engine is eating itself
#92
Also, on that track day, the true water temp was around 221, according to the Torque app, while the PCM showed the usual 194. I was in Sport mode, but on the 100-degree day, the cooling system was unable to bring the temp down to the usual 185.
Oil temp peaked at 246 degrees on Torque, but touched 260 on the PCM.
It would be nice, in general, if Porsche trusted its drivers with accurate instrument readings.
Oil temp peaked at 246 degrees on Torque, but touched 260 on the PCM.
It would be nice, in general, if Porsche trusted its drivers with accurate instrument readings.
#93
In hindsight, I think now that each of the different modes (normal, sport, sport+) just have different throttle and boost mapping, but each mode maintains the maximum HP at full throttle. after driving my 991.2 GTS for nearly a year, i find that sport mode has much more oomph early in the throttle than sport +. This makes sense because sport is normally for street and one does not have as much opportunity to floor the throttle on the street, so therefor the mapping gives more ooph and fun in the middle range of the throttle. sport+ meanwhile, is presumably meant for track, where one does pedal to the metal often, therefore the throttle mapping is more linear and constant, so one would have better cleaner linear control during the entire throttle range. but I want to believe that max hp is the same in both modes. normal mode too.
this still does not answer the fact that different modes seem to have different maximum turbo pressure. i'm not knowledgeable enough to know if same maximum hp can be achieved in each modes through the combination of throttle mapping and boost or if maximum boost pressure is ultimately what is going to bring maximum HP regardless of throttle mapping. maybe someone can give insight into that.
this still does not answer the fact that different modes seem to have different maximum turbo pressure. i'm not knowledgeable enough to know if same maximum hp can be achieved in each modes through the combination of throttle mapping and boost or if maximum boost pressure is ultimately what is going to bring maximum HP regardless of throttle mapping. maybe someone can give insight into that.
Last edited by usccharles; 08-07-2018 at 08:59 AM.
#95
Clearly the torque and HP curves change between modes because their max boost is occurring at different points in the rpm range but I think what is happening is that both peak HP and Torque are being constrained electronically to their advertised max.
#97
Yeah well today I did about 10 pulls from 2nd to 4th (991.2 C4S with 2100miles) and it should be boosting to 16psi. However all I saw today was 14psi in all modes once and saw multiple 13psi all day. It boost to 12psi very fast then takes its time to work up to 14psi (temp 40deg). I was in FL last week and saw 15psi for quick sec. My GTR hits max boost fast and stays there, is there something restricting the 991.2 from producing max boost and maintaining it?
TimboCarrera can you share you videos?
TimboCarrera can you share you videos?
a screenshot using sport response. I know this # is crazy for a base
stock 991.2 but here it is. My car seems to pull harder than a
.2 s I test drove. It is what it is. Flame ready.
#98
#100
#101
HAHA... surely the guy doesn't think the count down is the boost pressure! Say it isn't so!
Here is what I found...
Base/T: progresses to 10 below 5k then peaks to13 around redline
S: progresses to 13 below 5k then peaks ato 17 around redline
GTS (powerkit): progresses to 16 below 5k then peaks to 18 around redline
Powerkit give you significant torque in the mid range, but does slightly lag (torque comes in at a little later RPM).
Regarding my S: At low to mid RPMs, sports mode seems to let the car respond quicker (turbos primed?) than normal or sports plus, which seems to be better for revving it out (turbos stay spooled longer). Sports response button makes the car act just like sports plus, but does seem to allow slightly more boost (+1?). If you use sports plus and sport response button, you can spike to 16 PSI in the mid range (below 5k).
I use normal or individual (PSE and PDDC/sports SPAM on) mode for warming up the car and highway cruising. Sports mode and manual PDK mode (or at least always doing the up shift) for all other driving. I typically hit sport response button when planning to pass quickly. I don't really use sport plus because I prefer to shift PDK manually, PDK shifts uncomfortably rough, and you don't get PSE pops. If I went on a track, I'd probably put it in sports plus and let PDK shift itself, but its not really practical on the streets.
Here is what I found...
Base/T: progresses to 10 below 5k then peaks to13 around redline
S: progresses to 13 below 5k then peaks ato 17 around redline
GTS (powerkit): progresses to 16 below 5k then peaks to 18 around redline
Powerkit give you significant torque in the mid range, but does slightly lag (torque comes in at a little later RPM).
Regarding my S: At low to mid RPMs, sports mode seems to let the car respond quicker (turbos primed?) than normal or sports plus, which seems to be better for revving it out (turbos stay spooled longer). Sports response button makes the car act just like sports plus, but does seem to allow slightly more boost (+1?). If you use sports plus and sport response button, you can spike to 16 PSI in the mid range (below 5k).
I use normal or individual (PSE and PDDC/sports SPAM on) mode for warming up the car and highway cruising. Sports mode and manual PDK mode (or at least always doing the up shift) for all other driving. I typically hit sport response button when planning to pass quickly. I don't really use sport plus because I prefer to shift PDK manually, PDK shifts uncomfortably rough, and you don't get PSE pops. If I went on a track, I'd probably put it in sports plus and let PDK shift itself, but its not really practical on the streets.
#102
Interesting... I thought the peak for the S was 16, if you only get 1 more psi with the powerkit that would be a shame cuz its expensive and adds a little bit of lag. Ive seen folks post they hit 19s with the gts on the regular. Fwiw in my T I only consistently see 13 in sport + but it comes in around 5 grand and can spike to 14+ when you shift (with stock lungs-air filter/exhaust). I also havent been doing king kong downshifts like 2nd at 60+ or 3rd at 90+. Thats where the pdk really shines IMO. Puts you at the edge of the transmission capability for max power on the downshifts and keeps you on boost. Much bigger learning curve with the manual. If i had bigger turbos i would definitely do pdk to squeeze all that power out.
#103
I really wish someone would come up with the chip upgrade that doesn't increase the boost but just removes the lag of the boost in the mid revs, which is clearly programmed into the OEM software. Imagine a GTS (or any other model for that matter) hit its max boost from the get go. Even if the boost isn't increased past OEM, you would have significant power increase and oomph, and since youre not going over OEM max boost, it would presumably be safe for the motor. maybe someone already has a product like this available?
#104
Interesting... I thought the peak for the S was 16, if you only get 1 more psi with the powerkit that would be a shame cuz its expensive and adds a little bit of lag. Ive seen folks post they hit 19s with the gts on the regular. Fwiw in my T I only consistently see 13 in sport + but it comes in around 5 grand and can spike to 14+ when you shift (with stock lungs-air filter/exhaust). I also havent been doing king kong downshifts like 2nd at 60+ or 3rd at 90+. Thats where the pdk really shines IMO. Puts you at the edge of the transmission capability for max power on the downshifts and keeps you on boost. Much bigger learning curve with the manual. If i had bigger turbos i would definitely do pdk to squeeze all that power out.
Way I see if is its a turbo engine and I want more boost. Lag isn't a problem unless you're trying to drop the hammer at 2k RPMs. The way I drive is I'm either in eco mode or not. If you maintain 3k+ RPMs and use sports mode, response is instant in any model. From a stop becomes a consideration (a single time you can't rev at 3k...), but the car is able to get up and go with minimal hesitation (certainly much better than 991.1 PDK, which had some bad hesitation). If you want to pass, you're going to downshift and rev it out moments later. Thus, having more boost is just a plus and I wouldn't care about about any extra lag from low RPMs. I suppose an old school "NA MT" person is probably going to be shifting in and out of low RPMs (or just shifting below 3k in normal driving), so in that case they'd be happier with a less boosted engine...base or T car is perfect for them.
#105
I really wish someone would come up with the chip upgrade that doesn't increase the boost but just removes the lag of the boost in the mid revs, which is clearly programmed into the OEM software. Imagine a GTS (or any other model for that matter) hit its max boost from the get go. Even if the boost isn't increased past OEM, you would have significant power increase and oomph, and since youre not going over OEM max boost, it would presumably be safe for the motor. maybe someone already has a product like this available?