dyno tuning idea (part-throttle) - which dynos can do this?
04-13-2010, 04:09 PM
#21
Elite Member
Thread Starter
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
When doing multipe WOT runs one will typically overlay the torque vs RPM curves to see the changes easily. If the software can't plot torque vs MAP and overlay them, then it significantly reduces the utility of the technique.
Why would a 10 second sweep at say, 4000 RPM, from 40 kPa to 200 kPa, be harder on the tranny than a 10 second WOT sweep? Was that on an automatic?
Why would a 10 second sweep at say, 4000 RPM, from 40 kPa to 200 kPa, be harder on the tranny than a 10 second WOT sweep? Was that on an automatic?
Reply
0
0
04-13-2010, 04:30 PM
#22
Jason,
Not sure what your experience has been with the Dynapack but it will indeed hold wheel speed steady with varying load. The 99 Rental with the AEM you built, has TPS x RPM fueling with MAP correction. I watched Shawn Church go through the table, MAP moving both directions, RPM steady with occasional burps as he made changes on the fly.
Not sure what your experience has been with the Dynapack but it will indeed hold wheel speed steady with varying load. The 99 Rental with the AEM you built, has TPS x RPM fueling with MAP correction. I watched Shawn Church go through the table, MAP moving both directions, RPM steady with occasional burps as he made changes on the fly.
__________________
Reply
0
0
04-13-2010, 04:53 PM
#23
Tour de Franzia
iTrader: (6)
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,085
Total Cats: 375
Jason, we go from steady state to ramp runs at high load for a couple reasons. The most basic reason is to reduce high stress run time. It's to save run time on the motor, not to save the operator time.* However, a less obvious but equally important reason is so that we can try to predict the next load zones before hitting them. So we take our ramp run, observe, and if necessary change not just the zone that we're in, but all of the areas above and next to our current area that we haven't hit yet. Predictive tuning. Meanwhile the car is cooling down, and by the time we're done rescaling, the car is ready to pull again.
Our dynapack has a mode very similar to what you're suggesting--it just doesn't display the data in the manner you're requesting, but in terms of operation is pretty similar.
*Bear in mind that most tuners get paid by the hour!
Our dynapack has a mode very similar to what you're suggesting--it just doesn't display the data in the manner you're requesting, but in terms of operation is pretty similar.
*Bear in mind that most tuners get paid by the hour!
you're not joking about tuning by the hour. I couldn't believe how quick and essentially easy it was to tune my and my friend's cars.
Reply
0
0
04-13-2010, 05:06 PM
#24
Supporting Vendor
iTrader: (33)
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,659
Total Cats: 134
It may not plot torque vs MAP, but it does plot torque and MAP. Like I said, the dyno works in a manner like what you are requesting, it just displays the data in a different manner.
Reply
0
0
04-13-2010, 06:09 PM
#25
Elite Member
Thread Starter
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
And as I said, reduces the utility of the method.
Here: Why do folks do RPM sweeps on load holding dynos when tuning WOT, instead of doing it cell by cell?
Ans: to save time.
Emilio, I do understand how cell by cell tuning works at part throttle.
I am proposing a method of doing MAP sweeps while dyno holds RPM steady, instead of cell by cell, when tuning part-throttle areas of the map, in order to save time, and also so that the changes in torque with changes in timing, are easier to see.
Here: Why do folks do RPM sweeps on load holding dynos when tuning WOT, instead of doing it cell by cell?
Ans: to save time.
Emilio, I do understand how cell by cell tuning works at part throttle.
I am proposing a method of doing MAP sweeps while dyno holds RPM steady, instead of cell by cell, when tuning part-throttle areas of the map, in order to save time, and also so that the changes in torque with changes in timing, are easier to see.
Reply
0
0
04-14-2010, 12:36 PM
#26
Elite Member
Thread Starter
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
I emailed tech support at Rototest, Dynojet (they do have a load holding model), Dynapack, DynoDynamics, and Mustang.
The Dynojet 224xLC (load holding) model can't put MAP as the X axis.
The Dynapack can't do it.
I'm waiting to hear about the Dyno Dynamics.
Mustang tech support replied that their software can do it.
Just to be clear, here again is what I want to do:
Again here is what I want to do:
- pick an RPM row to tune in the ECU map (say 4000 RPM)
- set dyno to constant RPM mode at that RPM (e.g. 4000)
- start dyno datalogging of wheel torque and MAP
- driver slowly increases throttle opening over say, a 10 second period, so that the ECU slowly sweeps through all the MAP columns
- stop datalogging
- plot wheel torque vs. MAP from the datalog (MAP is the X-axis)
- change ignition timing in some cells from that RPM column
- repeat dyno "pull"
- overlay plots, examine which cells (MAP values) lost or gained torque and decide where to advance or retard timing
I'm surprised nobody has tuned part-throttle like this before. Seems like it's quicker than doing it cell by cell, in the same way that folks do an RPM sweep to tune WOT instead of doing it cell by cell at WOT.
The Dynojet 224xLC (load holding) model can't put MAP as the X axis.
The Dynapack can't do it.
I'm waiting to hear about the Dyno Dynamics.
Mustang tech support replied that their software can do it.
Just to be clear, here again is what I want to do:
Again here is what I want to do:
- pick an RPM row to tune in the ECU map (say 4000 RPM)
- set dyno to constant RPM mode at that RPM (e.g. 4000)
- start dyno datalogging of wheel torque and MAP
- driver slowly increases throttle opening over say, a 10 second period, so that the ECU slowly sweeps through all the MAP columns
- stop datalogging
- plot wheel torque vs. MAP from the datalog (MAP is the X-axis)
- change ignition timing in some cells from that RPM column
- repeat dyno "pull"
- overlay plots, examine which cells (MAP values) lost or gained torque and decide where to advance or retard timing
I'm surprised nobody has tuned part-throttle like this before. Seems like it's quicker than doing it cell by cell, in the same way that folks do an RPM sweep to tune WOT instead of doing it cell by cell at WOT.
Reply
0
0
Thread
Thread Starter
Forum
Replies
Last Post
