Load Dyno -

[Johnny_9]

-With the car on the dyno and wheels moving.
-Load has been set so that the car is cruising along at 3rd gear 10in/hg of vacuum
-The wheels are moving at a constant speed

Now with the car in those conditions, if I tune the timing and torque increases - how does this show up?

............decrease in load ???

 

[ecupro]

Well, torque increase, horse power will be increase.
You are in right chanel. What i mean is right timming.
Make sure there is NO KNOCK..ok.

 

[Johnny_9]

I read that you can detect more torque by less TPS on a load dyno....sifu's? Correct???

 

[ecupro]

You quote
"I read that you can detect more torque by less TPS on a load dyno....sifu's? Correct???"

Bro, i am not ecu lah.....how come i can detect the knock...he..he...he

Bro, while you cursing, you use less TPS and more vaccum. In tis case, the map will look for more advance ignition ( from Ignition map table ), torque should be increase.
Bear in mind, the engine "Knock".

 

[Joeker]

ECU professor,

I have some confusion.

You mention that dUring cruising, the engine ECU looks for higher ignition?

During cruising, engine speed is constant and vacumn is hi. What does the engine need advanced ignition for?

Ignition is advance to catch up with engine speed, no?

And why do you need torque during cruising?

If the Engine ECU notch up the ignition during cruising, what will happend if the driver floors the pedal? more ignition? won't that create pre-ignition?

AFAIK, the ignition advance of a carburator engine runs on vacumn and centrifugal advance. I think both have little or no advance during cruising.

 

[ecupro]

You quote :
"During cruising, engine speed is constant and vacumn is hi. What does the engine need advanced ignition for?"

Well, look at most ignition table ( like mountain ), you will notice that in high vacumn, the ignition will increase as the engine speed. So, if you crusing at 90km/hr at 2500 rpm, the ignition will be 25 degree, if you crusing at 110km/hr at 3200 rpm, the ignition will be 34 degree.

You quote:
"Ignition is advance to catch up with engine speed, no?"

Yes, you are right on.

You quote:
"And why do you need torque during cruising?"

If you have a torque during crusing ( if you can advance more ignition ), you can have less TPS and so less fuel ( a bit, right ) and have more mileage.

You quote:
If the Engine ECU notch up the ignition during cruising, what will happend if the driver floors the pedal? more ignition? won't that create pre-ignition?

Well, look at most ignition table ( like mountain ), you will notice that on loading or floors the pedal (low vacumn), the ignition will decrease as the ECU can not catch up the engine speed .( the ignition will like like down hill ), that means, the ignition will reduce. So, no pre-ignition,right. ( and also depend on the natual of the fuel )

Those who use turbo system, they have to reduce more ignition during high boost.

Well, please correct me if i am wrong.

 

[Joeker]

I think you and I are looking at this differently.

You are trying to say aceleration to cruising speed.

I'm trying to say, cruising speed itself, not accleration.

So, if you crusing at 90km/hr at 2500 rpm, the ignition will be 25 degree, if you crusing at 110km/hr at 3200 rpm, the ignition will be 34 degree.

Given the engine is stock N/A pumping regular gas, 34 degree iginition adcnace at cruising? isn't that rather hi? wat about WOT?

Well, look at most ignition table ( like mountain ), you will notice that on loading or floors the pedal (low vacumn), the ignition will decrease as the ECU can not catch up the engine speed .( the ignition will like like down hill ), that means, the ignition will reduce. So, no pre-ignition,righ? ( and also depend on the natual of the fuel )

I think I'm abit confuse

You said earlier that when at cruising speed, ignition is advanced by the ECU and now you say when engine is under loaded, the ignition decreases so that there is no pre ignition? I don get it.

Won't the ECU read from the TPS that the driiver wants acceleration and hence increases ignition timing for more torque? As you said it yourself, ignition timing and torque increase in tandem.

I mean the ECU reads and re-acts from all 7 (or issit 8 signals?) OB signals rite?

 

[speedchaser]

Car ECUs are very advanced nowadays that it could implement active variable ignition to any pre-determined loads and TPS.

What Professore tried to explain is true but he got it out from his system in a jumble up way though. :)

We have to acknowledge the fact that 'generally' (there is a counter argument to that on VEs, MBTs and such, but I'm not going into it now) the more ignition timing we run, the more torque we get and consumption will go lower because of better combustion.

In an active ignition system, even at cruising, the ECU will advance the timing as much as it can until the pre-knocking stage based on the common variables of TPS, O2, load or air-flow, temp, knock sensors, etc. The pre-knocking stage theoretically produce the most torque. (It's a fact in my car though.) Professore's Protech can't do this yet! hehehe...

When the car is under load as in flooring the throttle, engine load increases and timing will have to be retarded to prevent knock (pre-detonation).

Take a look at the link below. It's a good article on active ignition.

http://www.ecutek.com/tuning/ignition/

 

[ecupro]

Speedchaser,
Bro, Right timming....

You see, my product is very cheap......and your engine still alive,right...ha...ha...ha
Let we wait until Mr. Manan's product which benchmark M600, what u say ?

 

[ecupro]

To all,
Please drop in and have a look. You may have a better view on "ignition table" and the "mountain"

 

[RSI]

-With the car on the dyno and wheels moving.
-Load has been set so that the car is cruising along at 3rd gear 10in/hg of vacuum
-The wheels are moving at a constant speed

Now with the car in those conditions, if I tune the timing and torque increases - how does this show up?

............decrease in load ???

Depends on the load dyno:
If the dyno runs closeloop the roller speed stays the same and you will see increase in HP/torque reading.

If the dyno uses manual brake then the RPM will climb up.

A loading dyno has a eddy current brake that applies current to match the roller speed. That brake is connected via an arm against a load cell (something like a digital weighing scale sensor). When the rollers are held at a steady speed, the load at the end of the arm pressing against the load cell measures the weight/mass. So say if it is a 1 meter arm pressing 10kg (100N) on the load cell you have 100Nm torque. Since the roller speed is also measured, from there horsepower is calculated. Therefore different gear will have different torque to get the engine torque the speed at which you load is set to reference the engine RPM.

 

[RSI]

You need quicktime installed to see this video

http://www.geocities.com/robyndigital/3gp/Dyno_redhot.3gp

http://www.geocities.com/robyndigital/3gp/Dyno.3gp

 

[Johnny_9]

Should the ministry make Brake Dynos mandatory?

 

[speedchaser]

Oh yes they should! But then they should also build highways without toll mandatory!

 

[Johnny_9]

How much is a "brake" dyno

What do u call the "non-brake" dyno - "roller" dyno? - how mych?