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View Full Version : Is this turbo lag or a problem?



OhioMade
04-12-2013, 11:14 PM
I am about to roll past 500 miles on my baby.

I have not experienced any real issues, but every day on my way home from work there is a tight hairpin curve that I like to down shift into and then accelerate out of, and I have noticed that when I do this there will be a real momentary gap in power as I am leaving the hairpin and getting into the acceleration...this is my first turbo, so I am not sure if this is turbo lag or what... I am not noticing it on straights, just seems to happen coming out of this hairpin curve... any insight would be helpful. Thanks!

Ryephile
04-13-2013, 12:12 AM
Try it in Sport mode and/or with the ESC off. The e-throttle can be frustrating in normal mode.

Jjm4life
04-13-2013, 01:10 AM
Try it in Sport mode and/or with the ESC off. The e-throttle can be frustrating in normal mode.

This.
Turbo and tiny cc make for a awful lag. especially coupled with the basically dead throttle response of this car without sport mode engaged,

FTY
04-13-2013, 08:49 AM
Try it in Sport mode and/or with the ESC off. The e-throttle can be frustrating in normal mode.

Doing this should help tons..ESC full off.

mkawa
04-13-2013, 09:29 AM
ESC full off and a heavy foot is just going to spin your inside front. just do the first step off. i already get wheelspin on cold tires with TTC on, there's no speed to gain with the open diff by turning ttc off.

Dwaynek
04-13-2013, 09:50 AM
Install a sprint booster or power pedal and it should remove the lag

Thomas
04-13-2013, 01:06 PM
I don't think so. First off, if we are talking turbo lag, the power pedal won't address that lag. What rpm are you at powering through the corner. Power pedal might make the car feel more responsive, but won't make the any faster.



Install a sprint booster or power pedal and it should remove the lag

BigDaddySRT
04-15-2013, 07:32 AM
ESC full off and a heavy foot is just going to spin your inside front. just do the first step off. i already get wheelspin on cold tires with TTC on, there's no speed to gain with the open diff by turning ttc off.

There is no mechanical/ helical differential in the C510 Transmission.

The ESC System uses the ABS and ETC to control power delivery/transfer in the front wheels.


Remember the ESC Button is 3 Mode Operation.

Turning the Electronic Nannies Full OFF (Racing Conditions) will result in Better Performance.

mkawa
04-16-2013, 10:35 AM
the TTC is not really a nanny. it's an attempt at simulating an LSD, and a pretty effective one at that. The braking action on the slipping inside wheel loads the outside wheel with torque due to the nature of the open diff.

basically, in an open diff, torque goes towards the path of least resistance. a slipping wheel has no resistance and hence without TTC will receive all the torque, which is exactly what you don't want. the vectored braking action on the slipping wheel loads the inside wheel such that at least some torque is redirected toward the outside wheel.

obviously it's not as effective as a gear-based differential, but until one is released that will fit the c510, it's quite a bit better than nothing. the only situation in which you will do better without TTC is if you nail every single corner exit exactly such that attitude has flattened enough for both wheels to grip. this is like saying that running without abs is faster though, because it's a simple matter of threshold braking into the exact moment prior to lock-up..

BigDaddySRT
04-16-2013, 01:04 PM
the TTC is not really a nanny. it's an attempt at simulating an LSD, and a pretty effective one at that. The braking action on the slipping inside wheel loads the outside wheel with torque due to the nature of the open diff.

basically, in an open diff, torque goes towards the path of least resistance. a slipping wheel has no resistance and hence without TTC will receive all the torque, which is exactly what you don't want. the vectored braking action on the slipping wheel loads the inside wheel such that at least some torque is redirected toward the outside wheel.

obviously it's not as effective as a gear-based differential, but until one is released that will fit the c510, it's quite a bit better than nothing. the only situation in which you will do better without TTC is if you nail every single corner exit exactly such that attitude has flattened enough for both wheels to grip. this is like saying that running without abs is faster though, because it's a simple matter of threshold braking into the exact moment prior to lock-up..

You want to turn the ESC to Full OFF/ Partial OFF under extreme driving conditions.

If the ESC is Full ON, it doesn't react well to aggressive driving and will cut power via the Electronic Throttle Body.

mkawa
04-16-2013, 01:08 PM
yes, partial off is the way to go. this only leaves TTC on afaik

Ryephile
04-16-2013, 01:43 PM
yes, partial off is the way to go. this only leaves TTC on afaik

Word. The e-LSD will flash the ESC light when it's activating the inside brake, to let you know it's doing work and/or you screwed up your corner line.

I frankly don't see the point of full-off [press and hold the ESC Off button forever] since it only turns the car into a peg-legger.

shagghie
04-16-2013, 02:09 PM
Word. The e-LSD will flash the ESC light when it's activating the inside brake, to let you know it's doing work and/or you screwed up your corner line.

I frankly don't see the point of full-off [press and hold the ESC Off button forever] since it only turns the car into a peg-legger.

After three events, I've found I'm a second or two faster with ESC Full Off compared to partial off. I know others swear by having it full off, but I was skeptical taking it full off, especially the way these cars push if you are not smooth on the throttle out of the corners, again as you say, because of the wheel slip and the loss of tire contact patch as a result when grip is still needed post apex. But all of that said, I was surprised to see consistent time improvements with it full off. The car feels VERY different with it only partial off, and just feels 'weird'. Not sure how to describe it, but it feels like it's countering what you are telling it to do, but when in Full Off, it just does what you tell it, and it's on you to be smooth and not over-drive the course. This brings up a good point though, it may well depend on driving style as to whether having it Full Off or Partial Off yields an improvement for THAT driver. There is probably a certainty to which we should be able to say 'the car should be faster with it Partial Off', but that certainty depends a lot of the driver's ability to utilize the wheel breaking effectively, and not try to man-handle the car when it behaves differently than what you feel you are telling it to do. I'm not sold on which way is the fastest for me in the long run, but I can say with certainty and a lot of testing lately, that *I'm* faster with it off by up to 2 seconds on a 60 second course. I also have a lot more fun and feel like I am able to learn and adjust my entries and exits and adapt to the course better with it off as far as improving times and doing better. On a big track, I would imagine it is faster with it Partial Off almost no matter who the driver is, at least in stock trim, suspension wise. I'm more excited than ever for the next event now with the 28mm RTB on, and if I can get the ass to come out on throttle lift, it's going to be a hoot! I'm not saying getting the ass out is going to be faster...just that I can't wait to try it out!

mkawa
04-16-2013, 04:09 PM
don't want to turn this into a clinic, but the ttc kicking in does feel a bit funny. you feel the initial slip and then you counterintuitively have to keep pushing and the car will rotate (normally at the first hint of push on an open diff your first impulse is to back off). what you may be doing, since 2s is so gigantic a diff at qcom, is that when you feel the initial slip you back off, the ttc ends up just bleeding off speed instead of letting you vector torque, and then when you finally tip in out of the corner you're way behind. if you instead just push and trust the e-diff not to unicycle you, i think you'll get faster with it on.

shagghie
04-16-2013, 04:19 PM
don't want to turn this into a clinic, but the ttc kicking in does feel a bit funny. you feel the initial slip and then you counterintuitively have to keep pushing and the car will rotate (normally at the first hint of push on an open diff your first impulse is to back off). what you may be doing, since 2s is so gigantic a diff at qcom, is that when you feel the initial slip you back off, the ttc ends up just bleeding off speed instead of letting you vector torque, and then when you finally tip in out of the corner you're way behind. if you instead just push and trust the e-diff not to unicycle you, i think you'll get faster with it on.

All good points and I think you might be right. Truth is I ran first with it full off after reading all the other accounts of how it's better with it full off. So i prolly adapted from that as my benchmark, and being used to the car only pushing if i got on it out of a corner, conditioned myself to back off to regain tire patch and recover.
I did notice at the Abarth Experience how the ESC will help tuck the car back in when I just 'trusted through' and stayed in it on the big track when I was too early on a few apexes and ran out of run-off room. It was a pleasant surprise... it did (feel like it) slowed the car down, but the (corrected) line was so much better into the next corner it was more than worth it. Thanks for the recommendations... I'll be conscious of this at next event!

Ryephile
04-16-2013, 05:22 PM
After three events, I've found I'm a second or two faster with ESC Full Off compared to partial off. ...

Fair enough. Perhaps the stability control is simply slowing the car down. I haven't done any timed experiments between modes, I was just being hypothetical. Real world results certainly trump hypotheses all day long, LOL.

jguerdat
04-16-2013, 05:31 PM
First off, partial ESC not only gives you the emulated LSD but also still limits torque in the lower gears, although not as much as in normal mode. So, you may benefit from limiting wheel spin in partial mode but you're still being held back somewhat with the overall action. From the Owner's Manual (PDF version):

When in “Partial Off” mode, the TCS functionality of ESC (except for the limited slip feature described in the TCS section), has been disabled and the “ESC Off Indicator Light” will be illuminated. All other stability features of ESC function normally. When in “Partial Off” mode, the engine power reduction feature of TCS and the enhanced vehicle stability offered by the ESC system is reduced.

That said, I tried partial ESC for one run last Sunday and it made almost no difference in my time. As it turned out, it was my fastest run by ~.1 second. Not much and lost in the variability but noteworthy that partial may be useful on occasion. I have had no real problem with wheel spin with ESC fully off although feathering the throttle slightly may be necessary. I am running stock class so no boost controller here to contend with. Wheel droop seems perfectly adequate to limit wheel spin but more power likely would be a problem.