Gs450h dyno run in Germany
#1
Driver School Candidate
Thread Starter
Gs450h dyno run in Germany
Hey there,
I just had my GS450h dynoed today and it was a pain, the traction control kept turning on, although both dyno axles were linked. got 283PS and 622NM the most, the car wouldn't go past 160kmh. really annoying. an interesting thing that by 2500rpm, we measured 220ps and maximum torque, which made everyone wonder how this car manages Power.
I just had my GS450h dynoed today and it was a pain, the traction control kept turning on, although both dyno axles were linked. got 283PS and 622NM the most, the car wouldn't go past 160kmh. really annoying. an interesting thing that by 2500rpm, we measured 220ps and maximum torque, which made everyone wonder how this car manages Power.
#4
Lexus Test Driver
iTrader: (1)
I couldnt find gearing (or pulley ration in this case) ratios on that cvt, but for a standard GS 1:1 gearing is at 4th gear. This will give you the closes direct connection to the engine. So im assuming the cvt is geared close to the non cvt and that 4th gear is the best.
#5
Driver School Candidate
Thread Starter
don't forget that the transmission has 2 gears, usually shifts around the 120km/h when flooring it. all in all I am pleased with the results, as me and the dyno operator had zero experience in dynoing GS's.
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Mitrovich (04-28-20)
#7
Driver School Candidate
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#8
I ask because in a lexus presentation it was stated that the car is fastest in "D" as it can switch to the secondary cvt gear. It was on youtube...can't find it.. looked like an official lexus press event.
#9
The car switches to second gear regardless of the selected drive mode. S-mode pretty much makes sure that the engine is running (or at least it won't let it switch off once it has turned off - say, you blip the throttle), and provides some sort of way to control revs (kinda bad - a "hold max revs for the situation at all times" mode would've been better). It does mimic a stepped transmission when used as an engine brake, but if you floor it, it will just fall back to "hold max revs" mode. At any rate, maybe the car was freaking out due to acceleration sensors or whatever...
If you do the pedal dance to get into maintenance mode, I think the car locks itself in high gear, and it deff. turns off all stability control - just beware of the consequences of failure - you don't want the wheels to ever suddenly change speed. Read up on Back-EMF, and why teslas can't be towed (and what happens to the inverter if they get towed at high speeds)
You can also try to drain the battery in neutral until it starts beeping at you to switch out of it - I'd actually let it drain to 2 bars until it turns on the engine, then switch to neutral and then wait for the beeping. This should prevent the car from adding power from the battery pack - power should be almost the same (the battery can give about 30kw max), but the response will be way worse - "no torque fill" is the overly simplified explanation. MG1 needs power to push against the motor, and if the battery can't supply it... it all has to come gradually, so power increases gradually (engine -> mg -> engine -> mg, etc). Neutral on this car means no current flow from or to the MGs, or something along the lines.
A bit of clarification - EU gs450h uses a 3.266 rear diff, US&JDM gs450h uses a 3.769 (same as GS350). Explains why the EU one is a bit gimped in low-end acceleration. You might wanna try flooring while in high gear and at about 65kph during summer weather (i.e. right before the point where it shifts to low gear).. mine (EU) throttles until the car goes to about 100kph - I guess it doesn't like low revs, high gearing & high load on MG2, since the inverter's IGBTs hit 124 and kinda stay there (failure is at 170+). Doesn't really throttle come Winter. Theoretical top speed of EU model is ~285kph on stock wheels/tires combo, 249kph for the US model. This is assuming that MG2 does indeed have a max rotation speed of 14400rpm - the top speed might be limited a bit lower to have some leeway... dunno. I'm thinking about a gs430 diff (3.6 ratio) for mine, as US to EU shipping (3.769 diff only featured in US/JDM models afaik) might be a bit prohibitive.
Comparisons:
US:
- can't see the speed but the way it shifts is distinct - earlier and faster.
EU stock:
EU with GS430 diff: https://www.youtube.com/watch?v=qR9j...ature=youtu.be - check comments, shift point is obviously different.
As for GS's shifting slower overall, mine's kind of doing this, and the auxiliary transmission oil pump is making quiet chirp chirp noises when running (can hear it outside of the car when it's on and it's on electric power - the pump always runs when the car's on and the engine's not - maintaining oil pressure in the transmission), so I guess it's finally time to swap those bearings
The EU ls600h is a bit worse... takes about 200kph to reach max engine rpm
If you do the pedal dance to get into maintenance mode, I think the car locks itself in high gear, and it deff. turns off all stability control - just beware of the consequences of failure - you don't want the wheels to ever suddenly change speed. Read up on Back-EMF, and why teslas can't be towed (and what happens to the inverter if they get towed at high speeds)
You can also try to drain the battery in neutral until it starts beeping at you to switch out of it - I'd actually let it drain to 2 bars until it turns on the engine, then switch to neutral and then wait for the beeping. This should prevent the car from adding power from the battery pack - power should be almost the same (the battery can give about 30kw max), but the response will be way worse - "no torque fill" is the overly simplified explanation. MG1 needs power to push against the motor, and if the battery can't supply it... it all has to come gradually, so power increases gradually (engine -> mg -> engine -> mg, etc). Neutral on this car means no current flow from or to the MGs, or something along the lines.
A bit of clarification - EU gs450h uses a 3.266 rear diff, US&JDM gs450h uses a 3.769 (same as GS350). Explains why the EU one is a bit gimped in low-end acceleration. You might wanna try flooring while in high gear and at about 65kph during summer weather (i.e. right before the point where it shifts to low gear).. mine (EU) throttles until the car goes to about 100kph - I guess it doesn't like low revs, high gearing & high load on MG2, since the inverter's IGBTs hit 124 and kinda stay there (failure is at 170+). Doesn't really throttle come Winter. Theoretical top speed of EU model is ~285kph on stock wheels/tires combo, 249kph for the US model. This is assuming that MG2 does indeed have a max rotation speed of 14400rpm - the top speed might be limited a bit lower to have some leeway... dunno. I'm thinking about a gs430 diff (3.6 ratio) for mine, as US to EU shipping (3.769 diff only featured in US/JDM models afaik) might be a bit prohibitive.
Comparisons:
US:
EU stock:
As for GS's shifting slower overall, mine's kind of doing this, and the auxiliary transmission oil pump is making quiet chirp chirp noises when running (can hear it outside of the car when it's on and it's on electric power - the pump always runs when the car's on and the engine's not - maintaining oil pressure in the transmission), so I guess it's finally time to swap those bearings
The EU ls600h is a bit worse... takes about 200kph to reach max engine rpm
#11
Same power, different gearing. The eCVT can't ref the engine to max RPM off the line - MG1 has an RPM limit as well. There's a reason why the engine won't rev beyond ~3000rpm or so with the wheels not moving forward (hold in D and floor it), and why the car has a limited reverse speed. Bottom line is - the faster the output shaft spins (not related to MG2's gear selection), the faster the engine can spin. Main reason why 6600RPM takes 100KPH+. US/JDM version has shorter gearing = the engine builds power faster. If you were wondering why the LS/LC500h/Crown s220 3.5 hybrid (all 2GR-FXS, "multistage" hybrid transmission) can achieve faster launches with a similar engine - 4-speed auto transmission after the eCVT.
#12
Just curious if anyone has found a way to mod these hybrid beast? I know tuning is near impossible but how about a Cf drive shaft and/or the newly released lithium ion battery swap?
#13
Pit Crew
Not sure how I missed this thread! Great reference point for us GS450h guys...
Has anyone managed to get the engine past 5500rpm? Even when I floor it at WOT and engage the switch on the firewall, I'm seeing 5300-5400rpm max on my OBD meter. I've tried with a few scanners and same result, the engine tops out under 5500rpm no matter how hard I try, maybe to protect the MG1/MG2 electric motors from overspinning
Has anyone managed to get the engine past 5500rpm? Even when I floor it at WOT and engage the switch on the firewall, I'm seeing 5300-5400rpm max on my OBD meter. I've tried with a few scanners and same result, the engine tops out under 5500rpm no matter how hard I try, maybe to protect the MG1/MG2 electric motors from overspinning
#14
Pit Crew
I noticed on the dyno run posted by the OP, the engine cuts at around 5300rpm as well.
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