Fuel Injection How To: Often Forgotten Pre-Dyno Checks.

The checks that you should do before putting your car on the dyno, are pretty much the same checks and maintenance that you should do to your car on a regular basis.

Do you have anything around or near the exhaust; as the exhaust gets the hottest on the dyno.  So, if you have wiring that is close to the exhaust system, there is a good chance that it is going to catch on fire, or melt.

So, you want to make sure that you have nothing hanging around near the exhaust pipe, whether it be material wrapped, or you might have rubber line that is in braid, you really don’t want it anywhere near the exhaust.

Another thing to check are things like the condition of your engine’s fan belts.  Condition of radiator hoses.  It might appear fine for you to think that you can run the car with that fan belt on the dyne, and replace it later, because at the moment, it’s still spinning the pulleys.

But, once again, please remember, a dyno tuner is going to be getting the peak out of your engine, so, it’s going to be pulled to a higher RPM.  If that fan belt is in bad condition, for the sake of a $50 (or less) belt, it could come loose and take out a lot more in your engine bay while it is on the dyno.

Another thing to check, that a lot of people don’t realise, is oil condition.  If you haven’t changed your oil in 15 or 20 thousand kilometres, it’s going to be like slug.  Don’t put it on the dyne.

These were just a few examples of often forgotten pre-dyno checks.

For more information, you can contact Robbie McQueen at:

Advanced Engine Management / Wolf Motorsport
22 Melrich RoadBayswater, Melbourne
3153, Victoria, Australia
Ph: (03) 9761 3161

Let’s talk about Electronic Automatic Transmission control.

As far as complexity goes.  Automatic Transmission Control is about as complex as most control systems can get.

Using the Wolf V500 you can use a combination of MultiControllers and General Purpose Outputs to control a multitude of different types of transmissions.  And you are going to need a lot of these control systems, as some electronically controlled transmission require 10 inputs and outputs (just connected to the transmission) to control shift points and shift hardness, etc.

Auxiliary Inputs can be used to sense where the gear selector position is.  Some transmissions use only 1 wire for this, where others use up to 3 or 4 wires just to sense the selector position.

Auxiliary Outputs on the Wolf V500 can be switched or pulse width modulated to control which gear the transmission selects as well as line pressure and torque converter lockup.

It’s lucky the V500 has many auxiliary pins.

If we tried to explain the way the V500 controls the transmission in this email, it would appear very complex, and some people may be confused or even put off by this.  But there is nothing to worry about in that regard.  If you buy a Wolf plugin ECU that controls the automatic transmission in your car, your Wolf dealer will be able to help you tune the shift points to where you like them.  Or, you may be happy with them from the start.  We try to make the transmission shift almost like standard at very low throttle openings, and get harder as the throttle is opened, until it is a little more firm than standard at full throttle.

Once it is setup, it is relatively easy to change shift points and line pressure.

That being said, we currently only support that automatic transmission control is adjusted by selected Wolf Dealers, as it could be easy for someone to get themselves a little tangled up with this.

If you have a transmission in mind that you would like to control, drop us a line at wolfemail@wolfems.com.au

For more information, you can contact Robbie McQueen at:

Advanced Engine Management / Wolf Motorsport
22 Melrich RoadBayswater, Melbourne
3153, Victoria, Australia
Ph: (03) 9761 3161

BEFORE you start playing around with the idle control system on your ECU, you must make sure that the engine will idle as well as you possibly can, without the idle control system taking control.

Let’s talk for a minute about the most basic concept on how to set up your fuel and ignition maps so that you have the best chance of having a stable idle, even under varying load conditions such as when you turn the headlights on, or when the A/C comes on.

If your engine goes to stall, the RPM will drop and the load will increase.

So, you need to increase the amount of engine torque generated as the engine begins to slow down.  This will then try to increase the engine speed, and hence this will stop the engine from stalling.

How do you do this?

Let’s say that at idle (20% load and 1,000RPM) your ECU is delivering 3mS of fuel and 10 degrees of ignition timing.  We will assume the engine is running at an air fuel ratio of 14.2:1.  As the engine starts to slow down (you will see the increase in load and decrease in RPM), you want to increase the amount of torque the engine is producing.  So instead of 10 degrees of ignition timing, you might have 13 degrees at 875 RPM.  This will increase the amount of torque the engine is producing and the engine will try to speed up.

As it speeds up it returns to the 20% load and 1,000RPM point where there is slightly less engine torque, so it will begin to slow down again.

Now, and this is the important bit.  The idea is not to have the engine cycle faster, slower, faster, slower.  The idea is that the engine ends up “sitting” on this new torque slope.  Even though it may actually be going faster, slower, faster, slower, it may only be doing that by 20 -50 RPM, and you will not even notice that.

You can do the same thing with fueling, giving a little extra fuel as the engine slows down will increase engine torque, and help keep the idle stable.

NOTE: Don’t make these fueling and ignition slopes too steep, otherwise you will get cycling happening and the engine will not have a smooth idle.

Sometimes a car arrives for a dyno tune.  A pre-dyno check is done, all looks good.  You put the car on the dyno, you run it up, it makes good power.  A couple of tweaks are done on the test drive, a couple of cold starts, and the car is ready to go.  That happens….. Sometimes.

What also happens sometimes, is the car is dropped off, there is less than 1/8 of a tank of fuel in it.  You put fuel in it.  You do a pre-dyno check and find a couple of wires that are not terminated properly.  You fix the wiring.  You put it on the dyno, run it up the first time, and an intercooler pipe blows off.

You take it off the dyno, spend an hour going over the whole engine bay to make sure nothing is lose, or leaking, etc.
You finally put it back on the dyno, and the rest of the tune goes according to plan.

But it’s been a bit of an ordeal, and the tuner has been under extra time pressures, and you probably have to pay something extra for the extra time spent.

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So here is what you can do BEFORE taking your car with programmable electronic fuel injection to be dyno tuned.

The load added to the engine when the A/C is turned on can be several Horse Power.  That extra power needs to be generated by the engine in order for the engine to maintain the same idle speed as when the A/C is not turned on.

To help overcome this, you may need to use your Aircon Request Trim for fuel and ignition to increase or decrease the fuel being delivered, or increase the ignition timing to help improve engine torque under those conditions.

Until next time,