Can a VR Loom be used on a VP Engine
The only difference in the engines is the Cam Sensor which is fitted to the VR Engine.
If the VR Loom is fitted to a VP engine it will log a fault code of no Cam Sensor but it will operate normally and
not go into Limp Home Mode, if the Diagnostic Light is fitted it will be on when the engine is operating showing a
code has been logged, if this is annoying simply disconnect the light until it is
Can a VP Loom be used on a VR Engine
The only difference in the engines is the Cam Sensor which is fitted to the VR Engine.
If the VP Loom is fitted to a VR engine it will operate normally and will not log any fault
How do you Change a TPS
The TPS or Throttle Position Switch is fitted on the side of the Throttle body and Sensors the Position of the
This Switch operates on 0 to 5 volts with 3 wires (or as close to 5 Volts as you can get
Earth (Black/yellow on a VP)
5 Volt from Computer (Grey on a VP)
Signal voltage to Computer (Blue on a VP)
This switch when changed is often incorrectly fitted, the only way it can be set up is with a multimeter, the
signal out is 0 volts at closed throttle (or as close as you can get it) and 5 volts and Wide open
Throttle (WOT) (or as close as you can get it)
If incorrectly fitted or faulty will create flat spots and incorrect fuel and ignition
The Low Profile Sump Will Not Fit My New
The fitment of an aftermarket low Profile sump in most cases involves the removal of the hump on the centre of the
rear Main Bearing Cap.
Pinning Cam Bearings
The VP and VR engines from the factory had a problem with the alignment of the cam bearings, many engines spat out
a cam bearing under warrantee and they are still doing it today.
To ensure your engine will not do this use the race cam bearings and pin the centre two cam bearings, this was even
done in all of the Formula Braham engines using that block.
When a new cam is fitted it is important to make sure the cam is easy to rotate before any of the engine is
these engine usually run around 75 lbs oil Pressure if the pressure drops to 45 to 50 lbs it is usually one cam
bearing has been spat out, if oil pressure goes down to 10 lbs it usually means two bearing have
If the cam bearing are not pinned it is very common for them to move slightly and block off the oil gallery and
engine failure will occur very soon after this.
Which Belt do I use
There are two belts in use on the NOS V6 engines.
The original set up with the factory reservoir uses the 1510 Series belt so the reservoir is
If using a remote reservoir you can use the shorter belt being the 1500 series, this will allow the fittment of
aftermarket rocket covers without the power steering pressure hose fouling.
Point to note the 1500 series while the same brand as the 1510 does seem to stretch a bit when first ran so dont
forget to check the tension, the latest version of the alloy power steering bracket has been modified to allow for
The 1500 Series and new powersteering bracket are the way go if you can for the following:
shorter belt so less chance of coming off
Greater clearance on the Power Steering Pump outlet
Greater clearance to the bonnet on some cars this is a problem with the 1510
New Alloy Power Steering bracket is very easy to
The NOS Alloy Pulley set is using the 1550 Series Belt on the Wingless
The NOS Computer & Chip Failed the Max RPM
There have now been two cases where the NOS computer and chip has failed the Max RPM test when tested by officials
with the engine not running.
All of the NOS chips are sent out with the same Rev Limit, all chips are tested before being sent
Some people think that a faulty chip may increase the rev limit but this is not the case, if the chip is faulty for
what ever reason (welding on the car, jumper leads, wrong wiring loom, broken solder, etc) the engine will not run
very well at all, and we will replace the chip at no cost even if you broke it.
If an official tests your computer with their on car max rev tester and it does not pass get them
do it again
Test your computer on another car
Start the engine and free rev, even if the valve springs and injectors are not right you
will in most cases be able to rev the engine to the max.
Up to now Chips that have failed the official test have had nothing wrong with them.
Fuel Pressure and Flow Test
Fuel Pressure and fuel flow are two different tests but both must be correct for the system to
Fuel Pressure is check with the engine idling and taped into the pressure side from the fuel pump prior to the fuel
Typical fuel pressure for a VP to VT commodore is 350 KPA (50 PSI) without the vac line
Increaseing the fuel pressure by modifying the pressure regulator or using restrictors is dangerious and
To test the fuel make sure the tank is full, take off the return line put it into a 20 litre container and time how
long it take to fill with the engine idling.
VL style pump with take up to 8 min
044 style pump will take about 4.5 minutes
Do not just do half the test, if there is a proble with the system it will usually show up after 15 litres have
Fuel Filter (Before and after Pump and in
If you are running a fuel filter prior to a typical 044 EFI pump the filter must be at least 100 microns as the
pump does not have the ability to suck in an on road situation there is usually a pusher pump in the tank to ensure
you have a filter after the pump you must make sure it is designed to handle the pressure and is replaced or
cleaned regularly. Most Petrol EFI filters are not suitable as the glue in
the filter is not designed to handle methanol, the ideal set up is a stainless filter with a rating of 10 microns,
but this must be cleaned every meeting.
We now have NOS filters to suit the High Pressure side of the fuel system these should definately be
used when running any modern injector
With any of the modern Injectors you must run the baskets, it is recomended to change them each
Battery Isolator and Ignition Cut
Some classes insist you have fitted a ignition cut off, this is not the same as a battery
A battery isolator is fitted beteen the battery positive and the starter with all other positive wires
coming from the starter, this will not not stop the motor if it is running as the alternator is feeding the system,
but this is what you want on a wingless to save the battery and make it safe to change the injectors, or have kids
in the car for a pic.
An ignition cut off has to be in the feed to the ignition, with the power wire from the alternator going to the
battery side of this switch, this will not stop battery power to the starter and
If you want both you have to fit two switches.
Car is breaking down what do I do
The first step is to check the codes (See process and Fault
To reset code disconnect Computer or battery for 30 seconds
2. Exhaust Temp:
See what temp the exhaust is, you can do that by feeling close to the pipe or using a
this information will tell you if all cylinders are playing up so look for fuel or
coil pack or fouled plugs
If just one look for injector or spark plug
3. Fuel System:
Check the injectors are flowing correctly I will provide this service at no cost even
if not my injectors
5. Wriggle Test:
Check with engine running that if you wriggle a wire the engine does not
Make sure all screws and earths are tight
Always make sure you tie up the wires so they dont dangle and loosen a
Check the Crank Angle sensor connection it is common to damage the terminals I now use
a heavy duty "farmer" terminal to reduce this
6. Check Connections
Remove each connection and check for damaged terminals and
Use a Circuit cleaner or special Terminal Cleaner to ensure good
7. Voltage Test:
Check the volage is between 13 and 14.8 V out of this range the computer will go to
limp home mode.
If the alternator has a faulty diode it can still work ok but will spike Computer and
send to Limp Home Mode
8. Coil Pack:
- Having heaps of drama's from New coil packs would not recomend fitting one
- Always make sure you use a heat paste on the back of the coil pack to ensure the heat if
transfered from the coil to the engine
- If the coil over heats it will never recover and will need to be replaced
- When selecting a second hand coil pack ensure
- the spark plug terminals have not been corroded
- None of the coils have been replaced (if a coil needs replacing the base will
9. Valve Springs
- As these engines are standard and low in power you do not want a heavy
valve spring as this will cost you HP
- Engines miss firing at high revs can be caused by weak valve springs
- I note that it is often said you can tell this by free reving the engine, well my experience
tells me you cannot without some load on it
- A simple way to check the springs is to put the one fitted in a vice with the std one and close
the vice the weakest one will collapse first
- Note not all the valve retainers and spring listed on the recomended parts list are the same do
your home work