Another aspect of power distribution when wiring a car up or playing with the wiring in your car, it’s not an uncommon perspective to put the battery in the boot.

Now, when you take an OEM car that has the battery in the boot, like a Skyline, they run a battery cable up to a battery terminal in the engine bay.  Then they run from that battery terminal down to the starter motor.

The reason they do this is because the OEM factory know that a starter motor draws a lot of current and has a lot of electrical flyback.

They know that flyback can cause problems with other power distribution centres in the car.  One other thing is that with a starter motor you’ve got a couple of hundred amps being drawn when the starter motor engages, to turn that motor over.

So, the power draw here, could pull that power source down to 10 volts.  If you’re trying to drive 6 injectors and 6 ignition coils and a starter motor off 10 volts, it’s not really going to make a nice starting car.

So, if you are moving your battery to the boot, we recommend that you run a negative cable all the way to the engine, as well as to the chassis, and you run a positive cable to a remote battery post.  Then from your battery post to your starter motor.  

You don’t connect directly to the starter motor.  Connecting directly to the starter motor, even though it will save a couple of dollars in cable, and installation, you will have head aches further down the line, when you’ve got current draw and power losses when you are starting the engine.

One of the most common causes for bad fuel economy, poor acceleration and poor cruise driveability, may not be so much the way you drive the injector, but rather the type of injector you are running.

In this car, in this scenario, we’ve got 2 Bosch injectors, they look identical, but the spray patterns on the end of the injector can be the problem.  You can have a 15 degree conical spray, or a 30 to 60 degree conical spray.  What that means, is the atomisation of the fuel going into the cylinder.  

At a light cruise, something like on a Skyline, at about 2,200 RPM and 100 kph, you need maximum atomisation.  The airflow over the fuel injectors, the airflow into the cylinders is not at a high speed, so atomisation of the fuel is one of the best things.

If you have a poor quality injector, it won’t effect your power at the top end, you’ll still make maximum power, but your driveability won’t be there.  So, one thing is to look at the type of injector you’re fitting to your car, which is what we do here at Wolf Motorsport, we advise you on what type of injector to put into your car, and the right one of the job.

If you’ve got a drag car, and only top end stuff, then those injectors with the 15 degree spray pattern may be fine.  But, if you want nice economy, nice driveability, nice acceleration off the line, you’ve got to go for a 30 or 60 degree spray pattern. 

Power and economy is achievable.

One of the common things we do down here is rebuild rotary engines.

When we rebuild rotary engines, it really comes down to what a customer’s after and what the purpose of the engine is.

We are currently rebuilding an RX7 Series 8 engine, which the customer is intending on circuit racing.  For that application, we have chosen to go with a stud kit through the housings and through the end plates.  This is to increase the rigidity of his motor, and stop twist.

The other thing we have done with his rotors, all of his rotors have been side clearanced, which gives us extra clearance on the side seals and also the corner seals.

We always opt to use new bearings in all of our rotor assemblies, and also in our stationary gears.

The other thing we do, is to have all of our rotating assembly balanced, and we also get our shafts what we call "isotropic coated" to improve strength.

The other thing that is very critical are the oil control rings in the engine.  A lot of people fail to replace certain things like oil control rings and the different retaining springs behind them.  They must be replaced to maintain the tension in the oil control rings, side seals, corner seals and apex seals.

Apex seals and side seals are pretty much like a piston ring.  Apex seals gain a surface against a rotor housing, and the side seals work with the side plates.

One of the most common questions I get asked regarding tuning is, "How long does my car have to be there for?" 

By Rob Sabbadin:

What I wanted to talk to you quickly about today is different turbo chargers and some of the things that people do with manifolds, dump pipes, different gaskets and washers that are used.

With the manifold here that we have in front of us, this manifold’s been HPC coated and the dump pipe has been wrapped.

The purpose of this is to actually help with the spool-up time of the turbo.   If we maintain heat in the manifold it actually helps reduce the spool-up time.  So, this whole manifold has been HPC coated, also, the dump-pipe has been heat wrapped.

This is also good for heat distribution in the engine bay because it’s maintaining the heat inside the manifold and not expelling the heat under the bonnet.

Also, with a turbo it’s very important when they are bolted up to a manifold, that all new gaskets and locking nuts are used.  There can be a fair bit of vibration from an exhaust system attaching to a turbo which goes through the whole manifold.  It’s very common for bolts to come loose.

In this turbo here, it’s had all new nuts and studs put on with locking tabs, along with locking nuts.

An important thing with turbos is a good quality turbo to manifold gasket.  There are cheaper and higher quality gaskets available.  The type of gaskets that we use are the same as EOM gaskets, which is a thicker gasket, which is three shims internally which are folded together.

These gaskets give a lot more “crush” and is a lot better with heat, and they will handle severe heat all of the time without failure.

You can check out more information on Turbo Chargers and Fuel Injection by Rob Sabbadin.

By Rob Sabbadin:

A commonly asked question by people is whether cam gears on an engine are actually beneficial or a waist of money.

Our R&D will show that cam gears can be very beneficial.  Every engine has its own characteristics and different cam timings can vary between engines and the application.  Also, turbo size and other bits and pieces can make a big difference to the required cam timing.

Cam gears are generally 1 degree or 2 degree adjustable.  Either being 1 degree on the cam, or 2 degrees on the crank.

Advancing and retarding cams can give you more power down low, or up top, or it can also give you a midrange power gain.

The power gain that is needed with vary for the application of the engine.  Whether it was someone that was trying to be a horsepower hero, trying to get power at the top of the rev range and not really worry about the bottom half.  Or whether a customer wanted midrange and top end, or bottom end power, and not really worry about the top end.

As you can see from the results, cam timing has given us a very good increase. It has basically given us an increase from the get-go, all the way to the top of the power curve.  With this we have used exactly the same turbo charger boost, also, we have tried to maintain the same air fuel ratios.

When cam timing is changed, it does alter air fuel ratios, but we have made changes to make sure that was the same, and also ignition timing has been left the same.

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

“How is that possible?” I hear you ask.

Now, image that you are controlling a relay with your ECU.  The relay is switching when you make the output of the ECU go to ground, but the device that you are controlling (we’ll use the example of a fuel pump) does not start running.  If you disconnect the fuel pump from the relay, there is 12V there when the relay is turned on.  But, when you connect the fuel pump, the pump doesn’t run, and the voltage at the +ve terminal of the pump is almost 0V.

So, on the face of it, it did initially appear that the 12V from the relay was there and being supplied to the fuel pump, but the resistance in the connection at the relay meant there was only a very small supply of current.  There was not enough current to power the fuel pump.

If you just used an LED test light, you will think there is no problem here.  But you’d be wrong.  An old style test light may give you some more information, as it may glow dimly due to the resistance in the connection.
Sometimes you need to think outside the box if things don’t seem to be adding up.

As older cars running electronic fuel injection continue to age, these types of problems are going to occur more often and diagnosis is going to become more tricky than before.

Until Next Time..

So I thought a quick look at these might help you feel a little more comfortable when dealing with them.  So here we go……….

Like a tap, it doesn’t matter which way around the resistor goes, the water can flow either way.

Some capacitors can be wired either way around, but ones with either a – or a + must be wired a specific way.

Diodes have a band at one end.  Current flows from the end with no band, to the end with the band.