Shift Points - Sorry another thread

[Rawyzf]

Sorry for another thread, lol, just trying to understand what is best here.

Below is a picture of my last dyno with my mods.

Looking at the Dyno graph below you can see the Peak HP is at 5500 RPM. The Peak TQ is at 4500 RPM.

Looking at this dyno graph, does it help decide where you should be shifting while WOT? I am thinking that you should shift just after the peak HP and try to catch the peak TQ, if I am understanding what should be done? Or, do you want to be a little before peak TQ?

Currently, with the new TCM tune I got from Livernois with the Camaro 3.45 Diff, here are my shift points (by eye, as I haven't logged yet).

EDIT: I have uploaded my videos from you tube for each file.





First File:


Second File:


Third File:


Fourth File:

Dig:


Roll:


Fifth File:

Roll:


Dig:


Sixth File:

Roll:


Dig:



First File Comments: Feels pretty good. Wondering if 2-3 shift can be a little higher maybe.

Second File Comments: 2-3 shift got worse, too low of RPM to start for 3rd gear in my opinion.

Third File Comments: 2-3 feels great. Looking at the chart, looks like it's close to where it was with the first file. However, when rolling from 30 and then going WOT, I am hitting the Rev Limiter on 2-3 shift.

Fouth File Comments: I think this is great from a dig. Still hitting rev limiter though on roll.

Fifth File Comments: On a Roll I am no longer hitting the limiter on 2-3 shift. I think it's shifting a little high though still, somewhere around 6600. I think 64-6500 would be max. - DIG file added.

Sixth File Comments: Looks like this might be it. Roll was good, shifted around 6450 or so. Dig was good, but the 2-3 went up to 6400 or so, when it's usually been around 6100-6200. Might have been a fluke though, as I kinda rolled into it as you can see in the vid. Gonna try to take a few more vids to validate.

[SpeedRacerX]

Maybe guys like Charlie, Devilish, George, and others can jump in as I am still learning all this tuning stuff, best shift points, etc myself.

BUT...I can offer a couple of observations & ideas...

1. I thought we idled around 600-650 RPM?
2. With where your HP and TQ curves are, I would "think" you would want your limiter raised to about 6300 RPMs so the following shifts can happen without issue...
3. I think the 1-2 works well shifting at 6100 RPMs and dropping into your TQ peak range. You'll also minimize some 1-2 wheel spin and spinning into your limiter. Your DR's will help this 1-2 shift.
4. Then, IMHO, I would have the 2-3, 3-4, and 4-5 shift at about 6200 +50/-100 RPMs so that you are maximizing your power band and dropping down after shifts right past your TQ peak and right at about your HP peak.

That 2-3 right now seems low. Regardless, it would be nice if all three shifts were smoothed out.

Again, I could be totally off on this.

[drumsbh]

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[edmanet]

You should set your shift points about 300rpm after your peak HP. So that when the
shift happens you are still in the power band when starting the next gear.

EX: My car makes a peak HP of 478 at 6500rpm....so my WOT shift points need to be set
at 6800rpm in every gear.

You need to do the following:

-- Log a few WOT runs to see where your car really shifts.

-- then set WOT shift points which consists of setting the MPH and RPM in several different tables. And you can't just type in 5800rpm and 29mph to get the car to shift at those points. You have to
take into account tire size and diff ratio.

For EX: My WOT 1-2 shift in HP tuners is set at 5300rpm and 21mph. After looking at several of my logs from some runs at Cecil the car shifted at 6790rpm and 39mph.

[Devilish34]

You should set your shift points about 300rpm after your peak HP. So that when the
shift happens you are still in the power band when starting the next gear.

EX: My car makes a peak HP of 478 at 6500rpm....so my WOT shift points need to be set
at 6800rpm in every gear.

You need to do the following:

-- Log a few WOT runs to see where your car really shifts.

-- then set WOT shift points which consists of setting the MPH and RPM in several different tables. And you can't just type in 5800rpm and 29mph to get the car to shift at those points. You have to
take into account tire size and diff ratio.

For EX: My WOT 1-2 shift in HP tuners is set at 5300rpm and 21mph. After looking at several of my logs from some runs at Cecil the car shifted at 6790rpm and 39mph.

I think you need to look at shift time in the tune also..As you know it's a lot of trial and error to get it perfect(or as close as possible to that)...

[drumsbh]

this is going to take awhile as its all email communication with Vector for me atleast... damn

[Devilish34]

yep

[desertg8]

I disagree somewhat about shifting 300 rpm after peak horsepower. My tuner explained it to me that you want the most horsepower under the curve after a shift.

So you have to look at each situation individually. On this particular graph the op has his horsepower drop off dramatically after 6000 rpm. So in his case maybe 300 after peak wheel horsepower if that much. Maybe only 200 in his case.

I think my rear wheel horsepower peaks at 5800. You can view my graph under tuning. But I only drop eight horsepower in the next 700 rpm. So my shifts were set at 6500 with the ls9 cam. I have not run her with the new tune yet. So mine are set to shift 700 after maximum horsepower.

[hulkss]

Ideally you need to rev until the torque or driving force at the rear wheels falls below that of the next gear. Here is a plot for a crotch rocket bike. Shift where the rear wheel torque lines cross.


Here's a plot for a typical near stock G8. Good luck revving high enough to get the lines to cross. Just rev as high as you can without mechanical damage.

[Rawyzf]

Thanks for the posts and input guys.

I have asked Livernois to check out the thread for any input.

I have also tried to log the shifts with the Livernois built in scanner, but it keeps dropping on me. What other tools/scanners are out there that I can use to log?