Engine dyno tuning

[CHB]

well guys,
i just wan to know that by using engine dyno, we would be able to load the engine to certain RPM and kpa as we would like to, is that right?
let say i need to load the engine to 200kpa(of course it is a turbo engine) at 8000RPM, then i'm going to manipulate my ECU fuel table to archieve the desired A/F ratio, then i have to tune the ignition timing table to archive the high torque value from the crankshaft. once, dial in that 200kpa@8000RPM bin in my programmable ECU, then i moved on to next bin, let say 220kpa@8000RPM and so forth... do i get it right so far?

[lexsmaz]

Kpa is an air pressure abreviation, i think you mean Nm as in the torque figure or Kw as in power reading..

Sounds ok about what you are doing, except that is some pretty high RPM'S you are talking about, i pressume its a figure you are just using as an example .. .

[Gavatron]

Pretty sure he means 200kpa, as in 1 bar of boost, at 8000rpm.

You don't even know what engine it is. Why is 8000rpm so rediculous?

[CHB]

yeah the figure is just for example. in our programmable ECU, sure it has fuel and ignition map. when we tune it, we need to load the engine till specific load(RPM/kpa) if it is using Manifold absolute pressure sensor. so to tune the engine right, we need to load the engine to individual bin in our fuel, tweak around the VE value in order to archieve specific A/F ratio, then we advancing the ignition timing with respect to that engine load until we get max torque value. it just like we do road tuning, but because road tune we can't hold the engine in steady state i.e 200kpa/8000RPM all the time until we can actually tune to the right a/f. does any one get what i mean here?

[CHB]

i'm just workin it out what do ppl really do during engine dyno tuning, not chassis dyno i mean here. 8000rpm is the target redline for my engine

[Talasas]

As far as I can tell, you use engine dynos when you want direct readings from the engine without estimates for drivetrain loss. Also you gain the benefit of more easily accessing the parts should you want to make alterations to specifica parts (e.g. tuning an intake). Finally it's because you have the funds and access to an engine dyno.

All the dyno tuning I've had done on a drivetrain dyno before allowed the engine to be kept at a specific RPM and throttle position/MAP value so that tuning can be done...

[CHB]

i guess drivetrain dyno u mean is what normally referred as chassis dyno, isn't it?
thats a lot factors need to be consider including clutch slippage, drive train stresses and so on.
any also, getting readings from dyno on to know how much horsepower your engine make and it is different from what i want to archive.
actually, can we really load an engine to all the possible RPM/Load points?

[Celica RA45]

it depends on your ecu for fuel and ignition but some ecus you can set base points from 0 up every 400 rpm after wards to say 9200 rpm which normaly would be the same fuel base point as your rev cut at 8000 .on engine dynos most operators normaly set motor up with right lambda and run in 1st at about 3000 rpm and leave it for about 20min then go back to idle and start tuning from there

[CHB]

how much would it cost to tune our engine on a engine dyno(engine test bed) that you guys normally heard of?

[Hiro]

All the dyno tuning I've had done on a drivetrain dyno before allowed the engine to be kept at a specific RPM and throttle position/MAP value so that tuning can be done...

The engine dyno setup we had at uni for our thermodynamics course had an early 4AFE set up on it, we could independently alter throttle position (through a compressed-air actuator, previously just the throttle cable sticking through the wall), engine rpm, and load (and as a combination of these, MAP), so you could re-create just about any situation the engine could be expected to see. Pretty sure all of this was using standard ECU though.