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-   -   Smooth Throttle for UpRev (http://www.the370z.com/tuning/43384-smooth-throttle-uprev.html)

wstar 10-16-2011 09:30 AM

Top post updated with new results, and a new, better map. Read that post for all the updates...

cdoxp800 10-16-2011 10:10 AM

Impressive work wstar

Zat_Zuma 10-16-2011 11:02 AM

Excellent work ......repped

N8GTOL 10-16-2011 11:34 AM

Nice write-up :tup:

DIGItonium 10-16-2011 05:17 PM

Great work! I'd love to see some videos. No wonder I had issues getting boost to build up at times especially when starting out at very low revs, and it takes forever to rev up to redline in 2nd as if the throttle is barely opening up.

I'm sure you've given tuners a great starting point.

Even though I can't edit the ROM on my own, perhaps Sam can take a look at this and send me a new flash. Maybe I can keep the standard response for daily driving and this one can be the "sport" map.

wstar 10-16-2011 06:11 PM

Well, even the "naive" approach will open that up for you, supposedly. The point of this exercise is to get that benefit while retaining a smooth, predictable response. I imagine some people will actually feel like their car is slower on my map, because in theory it should smooth the acceleration curve, resulting in less Jerk and/or Jounce which, I believe, is what leads people to believe the car has a very "snappy" throttle response based on Seat-of-the-Pants. I prefer predictability.

I have some more datalogging to do to back this up, and to make some estimation about how the 3800's concept helps low RPM driving force in general (smoothed out or not).

My plan for those charts is to log basically just rpm-vs-time (plus a few other parameters for my own validation) as an accurate vehicle speed metric, do it for a 2nd gear pull flooring the pedal from 1500 RPM on a few different maps (assuming I can do that without wheelspin, otherwise I'll go to 3rd again), and then derive accel -> jerk -> jounce data from that, or at least to whatever practical limit there is in the data.

wstar 10-16-2011 08:15 PM

I did some data logs between the good curve and the stock map on raw acceleration with a stomped full throttle from 2k -> top in 2nd gear, and to be honest at first glance the difference isn't huge.

Of course this isn't engine tuning, this is throttle tuning, we don't expect to make the engine accelerate any faster in most of the range. What I expected was a notable difference in the acceleration in the low RPM range though, basically from allowing the virtual pedal to fully open like the real pedal did, and what I found was a relatively small one (in the right direction). Subjectively, the effect seemed a lot more noticeable though. For the short time window that matters we don't have a ton of sample points either, and there is a tiny bit of sensor -> cipher lag as well. All of that could be dampening the results.

Don't have time to run the numbers on the numbers, but I'll do that later and make some graphs.

wstar 10-17-2011 08:46 AM

Well, for now I'll stick by my subjective impression (which was fairly strong) that UpRev and the tuners are right: maps with a solid column (or more) of 3800 values at the end do get on the throttle quicker at lower RPMs when you stomp the pedal all the way.

The MPH and RPM data via Cipher simply isn't good enough to infer g's of accel at the fine scale needed to tell the difference between the stock and non-stock maps at low RPMs in the scenario above, and adding to the error is my inability to get the graph start points lined up precisely (same starting pedal pos + rpm, leading to same timestamp for first full-throttle sample).

I'll post up this chart here anyways so you can see what the data looks like, but the bottom line to me is "too noisy and inaccurate to tell anything from". MAP4 is stock, MAP3 is one of the 3800 maps (the 2300 one in this case, not that it matters which at full throttle):

http://www.the370z.com/members/wstar...onclusions.png

DIGItonium 10-17-2011 12:44 PM

Have you driven a DE/HR car lately? I wonder if you can get your impressions with those cars in comparison to your map.

So how's daily driving coming along?

wstar 10-17-2011 01:40 PM

No, I've never driven the DE or HR motors. Daily driving on the "curve 2300" map is great, but so was the "curve 2700" as long as you didn't go full throttle, and the original "linear" was pretty decent as well, although it seemed a little snappy or sensitive in the upper parts. Really even the stock map is reasonable too, so long as you're always at say ~3.5K+ RPM. The tuner map was kinda awful though, lots of odd unpredictability at partial throttle.

Sorry I haven't posted a video. I actually have a good setup for shooting video out the front windshield (which I used for this), but not for recording my dash dials while driving. I'll take some video on stock vs curve2300 sometime this week though, using aLapRecorder and virtual gauge overlays for RPM and TPS, like I did for the track stuff. I just need to get it all set up again after (yet again) updating my beta android firmware.

DIGItonium 10-17-2011 06:25 PM

Hmm... wonder if Sam@GTM would be willing to load your tables in one of the slots. I'd be happy to test it out for you. However, I'd be curious about the difference in the stock tables for 7AT versus 6MT.

I can keep the stock table for normal or wet weather driving, and then switch over to a snappier setup on dry days.

Ron 10-17-2011 06:31 PM

Digi with the version of uprev that you have do you have access to at least look at the tables? You can compare your table to the wstar's stock table on the OP. I'd too be interested to know if they are same.

wstar 10-17-2011 06:41 PM

Basically unless he gets a Tuner license for that cable, no, he can't see the tables.

zguynate 02-24-2012 12:20 AM

Any updates on this? What has your adjustments done for throttle response as well?

Jordo! 02-24-2012 12:29 AM

The stock map mirrors the stock power curve, right down to the drop in power before fuel cut and then the sudden spike.

The 2700 curve actually looks to be the best to me -- how does it feel compared the 2300 curve? Too jerky at upper range?

Did you try 2500?


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