Steady State Load Bearing Dyno Tuning Question..

[Stuffs]

when doing tuning on a load bearing dyno whats the correct way to do steady state corrections (VE and MAF via afr error %)?

** First option is the dyno roller speed , to hold the dyno at certain speed and the tuner seeks the cell to hit with car gears and throttle.

** Second option is to tell the dyno to hold (increase or decrease load ) to hold the engine at selected rpm with signal picked from a spark plug or reflective mark.


i am not a tuner so if there is more options let me know too add them to the poll please

[Keith@HPTuners]

I'm not sure what the difference between the first two options are. Then goal of steady state is to isolate cells specifically to dial them in, and you can achieve that with either option, which, to me effectively seems to be the same.

[ElecTech]

I typically pick and RPM set point and then vary the load with the pedal to populate the cells I need.

[Keith@HPTuners]

Yea, I suppose you would need RPM pickup for automatics that use torque converters.

For manual transmission vehicles, I think they would be the same MPH controlled vs RPM controlled.

[MikeOD]

I selected RPM in the poll because the VE tables in everything I've tuned reference RPM. Seems easier to me to just tell the dyno "hold 4000 RPM" than it does to watch the RPM as I change MPH to figure out what MPH I need to hold it at.

[GHuggins]

I use mph, then use what ever gear I can get the trans in for rpm selection. This way I can get as much data as possible with each test pass by changing the rpms and using the load held on the dyno and throttle to dial in higher "load" areas in the cells... Only down fall to this is lower gears can overtake the dyno on the higher hp builds, so you have to pay attention to the load dials on the dyno to make sure your not overloading it and you do have to get out occassionally and change the mph settings. Typically you can set the dyno up for 3 to 4 different mph settings to get all of the sd and maf dialed in...

I can see the benefits of the rpm selection, especially on auto's, but I don't know if I like the idea of having to change the rpm settings constantly? Don't know, I may have to give it a try someday. Right now I just like being able to hit as many cells as possible without having to reset the dyno...

[mowton]

I use mph, then use what ever gear I can get the trans in for rpm selection. This way I can get as much data as possible with each test pass by changing the rpms and using the load held on the dyno and throttle to dial in higher "load" areas in the cells... Only down fall to this is lower gears can overtake the dyno on the higher hp builds, so you have to pay attention to the load dials on the dyno to make sure your not overloading it and you do have to get out occassionally and change the mph settings. Typically you can set the dyno up for 3 to 4 different mph settings to get all of the sd and maf dialed in...

I can see the benefits of the rpm selection, especially on auto's, but I don't know if I like the idea of having to change the rpm settings constantly? Don't know, I may have to give it a try someday. Right now I just like being able to hit as many cells as possible without having to reset the dyno...

Its just a right arrow key stroke or 2 to advance to the next RPM Breakpoint or a left arrow to decrease....

Ed M

[MikeOD]

Its just a right arrow key stroke or 2 to advance to the next RPM Breakpoint or a left arrow to decrease....

Ed M

Yeah...bring the keyboard into the car with you...I usually have all kinds of wires (wideband data, wideband power, HPTuners cable) under my feet...what's a few more?

[GHuggins]

Its just a right arrow key stroke or 2 to advance to the next RPM Breakpoint or a left arrow to decrease....

Ed M

I know I don't have the dyno wired into my laptop, which requires me to get out and walk around the car everytime Just laziness I know, but the mph works out very very nicely for me Allows me to hit the most cells at one time possible...

[GHuggins]

Yeah...bring the keyboard into the car with you...I usually have all kinds of wires (wideband data, wideband power, HPTuners cable) under my feet...what's a few more?

^^^ Yes, I know..... But I already have my laptop in the passenger seat, all wideband and wires under or behind my feet with main wideband display hanging from the mirror, so that would have to go in the passenger floor

Funny seeing peoples reactions sometimes to all the wires hooked up and stuff hanging around their cars....

[Keith@HPTuners]

Sounds like we need to go wireless.

[mecanicman]

Using a mustang dyno I first use the speedometer check function with the vehicle in direct gear and use hpt tuners to watch engine rpm. I have a sheet with the each rpm break point on the ve table and write the speed that lines up with that rpm on the sheet. I set the dyno to hold that speed and use the pedal to move my way through the table. If no one is around to run the dyno I have a wireless mouse I bring into the car that I can change the speed to the next point with.

[mowton]

Sounds like we need to go wireless.

^^^^ Agree :-)

Ed M

[MikeOD]

Sounds like we need to go wireless.

Only if you can talk NGK/ECM into making a wireless version of the trusty AFX/AFM1600.

[GHuggins]

Sounds like we need to go wireless.

You get those handhelds out to where we can provide multiple tunes with a tuner and we won't worry about the wires or possibly a datalogger that works?

[LSxpwrdZ]

I use both for various setups.

Using a Digital Dyno Dynamics 450DS with a MicroFlex handheld for wireless control. Simple toggle up/down for coarse mph/rpm adjustment or left/right for fine mph/rpm adjustment. The RPM feature uses whatever tach method you are using to generate RPM. My inductive pickup works like a champ so 99% of the time its using that.

[Stuffs]

wow thanks for the inputs!

only the mph worked on the one we are using.

when tuning a A4 stalled C5 , do i have to lock up the TC? or leave it as is and manual shit it to the desired rpm/mph/kpa cell? whats a good load % to do WOT sweeps for MAF and for SD VE model tuning?

[LSxpwrdZ]

I personally don't care much for the % load feature. I use either the constant steady state MPH or RPM to get a good starting point and then use controlled sweeps at a desired acceleration rate at various loads to verify acceleration fueling.

[Stuffs]

thanks James , and what about the usage on a stalled auto car? use 3rd and lock up the converter?

[mowton]

thanks James , and what about the usage on a stalled auto car? use 3rd and lock up the converter?

...set the 3-2 down shift to 1 mph ( I do both part throttle and wot), tc lockup in 3rd to 10 mph and release to 5mph and 3rd gear manually selected.

Voted -- constant speed :-)

Ed M