112 | Dyno Operation (Intermediate) - Mainline AWD1200

Hi,

I have a few questions i would like to know more about it ..

Do i have to do Derived RPM option for each rpm while tuning for steady state condition? as i saw in some vid that u don't need to Derived RPM each time to adjust the rpm reading .. but when i saw this vid a got lil confused .

Also does connecting the dyno to SPARK PLUG COIL will let me do steady state or do i have to do Derived RPM to make the car work with the dyno ?

last time i did connect the dyno to the coil but the dyno didn't read my rpm, it was dynojet and the owner said today it's acting like that with many cars ,but the next day it read for my friend's car. What usually cause that issue ??

Last question : Many tuner at here has a dynojet and im trying to know, How they tune the cars without a steady state condition?

as i learned Steady state is the best way to get better tune at low rpm.

UP UP UP

There are a few different ways of getting rpm into the mainline dyno. You can calculate rpm from road speed and gear, measure it directly via an ignition source/spark plug wire, or take it from the ECU via CAN. It's not specifically essential to have an rpm input though to tune in steady state. the dyno natively controls roller speed and unless you have an automatic trans, the relationship between wheel speed and engine rpm is relatively constant. This means you can just use the dyno to hold a fixed wheel speed. As the engine produces more torque the wheels tend to climb onto the braked roller and deform slightly so you may find the engine speed tends to increase a little as the torque increases so you need to constantly make small adjustments to the roller speed as you change throttle position.

If you're using an inertia dyno then it's impossible to accurately map the engine in steady state. Most tuners just don't bother, or alternatively do a cursory job of making the air fuel ratios somewhat in the ball park and call it done.

Thank you Andre for your reply .

as im still new in tuning world. i would like to clear my mind.

How to calculate rpm from road speed and gear?

Also when i want to control the roller speed all i need to do is changing the speed at the dyno as it showed in the vid?

And if i do that it mean with each speed which i choose it should give me a difference rpm reading to hold it, am i right?

UP

The relationship between road speed and engine speed is fixed for a manual transmission vehicle. The Mainline dyno allows this relationship to be set in the software so that it can display an engine rpm from road speed.

You can adjust the roller speed using the F11/F12 keys or Shift + F11/F12 or Control + F11/F12 to make large, medium or small changes. This will change the engine rpm that the engine is operating at. You will find that the engine speed does climb a bit at a fixed roller speed as you go from light throttle to full throttle though.

If you haven't watched it already I'd recommend you have a look at this webinar too: https://www.hpacademy.com/previous-webinars/098-dyno-setup-and-operation/

Andre, have you ever tried using the DBW setting to maintain a specific load value while steady state tuning? I noticed on the most recent webinar that the torque plot was quite jagged while performing the timing run, and you mentioned that it was due to the load value varying during the run. I was thinking you may be able to lock the throttle position at a specific value during the test to eliminate one variable.

Mike

Yes it's possible to do so, however the reality is it's not really necessary and adds another factor that takes time. While a slightly erratic torque plot is not ideal for demonstration purposes, it really makes little difference and I tend to simply mentally smooth the plot. You'll also find in many instances that the relationship between MAP and TPS isn't fixed. Particularly as a turbocharged engine builds heat in the exhaust manifold and turbo, you'll need less throttle opening to maintain a fixed MAP value.

I've recently started using a Mainline awd dyno and wondering if anyone has the list of keyboard shortcuts.

I'm not sure if there is a master list of shortcuts sorry? Might be worth emailing Todd or Craig directly and asking.