I strongly feel that the Ecotec V6 is basically
a performance orientated engine at factory specification. If you
study the upgrades and compare to the VN,VP & VR engine specifications,
it is soon apparent that while these engines may look similar
that is where the similarities end. This engine was a massive
upgrade including revised cylinder head porting, lighter pistons,
cross bolted main bearing caps, ungraded engine management and
the list goes on. I believe with some basic and sensible upgrades
that this compact baby will respond with serious results.
The engine will remain naturally aspirated
with the rebuild not intended to be super extensive. The primary
objective will be to keep it simple yet very effective and most
Initially I will start by bringing the engine
back to as new mechanical condition. I am not going to waste time
fitting expensive high performance parts to an engine that will
not hold compression. Primarily the focus will be on engine breathing.
Careful consideration to be given to camshaft selection. I am
going to talk to all prominent suppliers of camshafts & components
and hopefully select the right combination for this engine. Cylinders
heads will be reconditioned with possible porting and valve upgrading.
Cold air induction is a must. Extractors will definitely go on
and I want to set up the exhaust just right as I want a great
sound also. This is a very basic plan to begin with and I am sure
that as I progress through this journey that several other modification
will be included.
Now, time to transform our factory specification
VS into a credible My Street Car.
Before I start tearing the engine down its
time for a dyno run to see just what our standard V6 Ecotec is
capable of This aspect of the build is considered vital for the
purpose of establishing our benchmark and starting point for all
future modification comparisons. This is a results driven project
with the success of this build being determined on genuine performance
gains achieved. Guess work will not suffice.
Our stock Ecotec won't know what hit it after
spending all of its previous life at no more than part throttle
so some pre dyno tests, checking and tuning will be time well
spent in our workshop. I will set the standard existing engine
up to a satisfactory state of tune and service eg, no breaking
down spark plug leads, filters in good order and just basic preparation
to ensure we are mechanically sound. Dyno runs do not come cheap,
so ensuring our tune status is to a high standard will hopefully
give a clean power run on the first attempt.
Our pre Dyno preparation has included a run
on the tune scope, scanner hook up and general mechanical condition
assessment. Fortunately no real problems discovered. Spark plug
maximum KV's were a little on the high side with an inspection
of the spark plugs revealing units that appear to have done a
minimum 40 000k or more. With new spark plugs fitted, KV's are
back to normal, the coils are happy and the ignition is ready.
Air filter & fuel filters: OK. The transmission oil was more
a greater shade of varnish so just for good maintenance, I carried
out a transmission service as there are some hard days ahead.
With that done we are all good and ready to rock & roll.
In conjunction with the dyno run, I will also
have a temperature sender fitted in the air filter box. Air temperature
& density have a major influence on power output so I feel
logging induction temperature will be worth while for later reference.
Having had no previous association with any
of the dyno shops in our area, the challenge was now on to find
a quality dyno equipped workshop to power run the My Street
Having spent several years working with both
engine and chassis dynamometers earlier in my career, I have a
better than average understanding of dyno operating fundamentals.
I have seen the good and the bad. Engines bouncing off rev limiters,
under bonnet parts melting, stuff like that...!!! So I really
wanted someone who knew what they were doing to ensure the car
would be looked after and more importantly the information was
The word had been out for some time that Nathan
at The Throttle Shop in West Gosford was the man to see for dyno
work as they sport a Dyno Dynamics 2WD unit that prints off the
now well known power run graph which also incorporates air fuel
ratio logging and air induction temperature correction. Well,
it doesn't get much better than that and Nathan certainly didn't
let us down. Very professional and all this done for a very reasonable
Nathan was kind enough to let us watch the
dyno run and and take some photos. Man, I just gotta get myself
one of these, the memories returned, this is the best toy a mechanic
could have. Even brought Kim over for the chance to check out
what it was all about. Whilst I did get the Yeah, Wow...
factor from her, the mood soon changed when I suggested we sell
the house so as we can buy a chassis dyno for our workshop.
Nathan gave the My Street Car a series
of brief power runs to establish a mean average. Once the power
started to fall away the show was over and time to back off. Nathan
certainly had a real feel for his work and all went very smoothly.
Well, check out that graph...!!! The
stock Ecotec handled this like a trooper, was consistent and produced
some damn fine numbers. 102.60kw with as little as 2kw between
runs is a good result. Conditions for the dyno run were cool with
ambient temperature approx 15c and air box temp approx 20c due
to air box proximity to the radiator and general heat soak from
the engine bay. The engine sounded great and run clean with only
a puff of grey smoke from the exhaust towards the end. Not bad
for an 11 year old engine.
With the dyno run now complete, we now have
a starting point from which to work from. Where we will peak,
only time will now tell. I am really excited now with the thought
of unlocking the potential of this engine.
Well, that concludes the introduction and initial
web site presentation for this project. Time to now soon get dirty...!!!
Just for a few weeks though, I am going to
stall the build while I commence correspondence with camshaft
and engine parts suppliers etc. I feel a little homework now will
be time well spent to ensure we get it all just right before we
take to the tools. I would love to receive some feed back, perhaps
even some helpful hints or recommendations.
Hope to be back real soon,
Whilst preparing the final dyno results,
I overhead some breaking news on the radio that has floored me
fair and square in my tracks. Concentration is lost, I am in shock..!!!
Today is the 8th September, 2006. Peter Brock has been killed
as a result of a car accident whist competing in a Targa event
in Western Australia. This is something that I just cannot comprehend
at the moment and is certainly news that is hard believe or accept.
Throughout my life has been inspired so
much by this man. His motor racing ability, Holdens and just the
character of Peter Brock gives you energy and drive to believe
in yourself and achieve your goals. That is the power of Peter
Brock to people like us.
Yeah, it's a bit sad hey...!!!
Peter Brock is a legend, larger than life
and forever "King Of The Mountain"
Welcome back to the journey of My Street
Car and perhaps the most interesting section of this project:
The engine rebuild phase. There was
never any question that the rebuilding of the V6 Ecotec engine
was going to be the most challenging aspect of this project requiring
patience, careful planning, research and quality workmanship that
would ensure the V6 delivered the goods upon start up.
I strongly believed from the start that this
engine had the potential for surprise...!!!
However, I also I knew there was a risk of failure. A poor result
on the dyno would have been devastating. Aside from the money
spent, it would have been very embarrassing. There certainly were
a few anxious days on the lead up to dyno day
The conclusion...??? Just over a 30%
genuine power increase. No fixing or fudging of
numbers. The standard engine was even serviced and tuned before
the initial dyno run to ensure net gains made with the modified
engine were actual in every aspect. A Dyno Dynamics
Chassis Dynomometer was used to once again ensure
there was going to be no mistakes and variables such as air intake
temperature would be calculated and corrected into the final power
My Street Car is just wonderful
drive. The engine really does sound magnificent, clean and crisp.
On start up, you really know there is something going on under
the bonnet. The exhaust gives a deep note and the engine really
lopes at idle (which I don't mind at all). Whilst the engine does
lope, it has never stalled. Once off idle, the engine is smooth
and upon mild acceleration the engine feels like any other V6.
It feels strong right from the word go and there is certainly
no loss of performance whilst driving at suburban speeds. Where
you really feel the difference is when you accelerate hard from
3000 rpm. This is where the engine really bites and within seconds
you’re at redline. Freeway performance is fantastic...!!!
I took the vehicle for a run up to Taree (a round trip of approx
500km). At 100-110k and in overdrive, the engine was just happy
to sing away all day at 2000-2200rpm, no hesitation, faltering
with the camshaft, just perfect. However, peg the throttle with
the need for passing and the engine explodes into life displaying
an unbelievable transformation of performance.
It is difficult for me to explain just how
tractable and user friendly this engine feels and when needed,
provides great performance. Its certainly now a good all rounder
and at the moment I feel I am just out of the starting blocks,
so to speak, with learning and discovering ways to further develop
I hope you find the following build report
enjoyable and informative and perhaps in some way help interested
persons who may be contemplating a similar rebuild. Whilst I have
endeavoured to cover most details of this build, it is simply
not possible to address every small detail. So I am
sorry if you find something I have left out. However, all the
good bits that count are in...!!!
If you ever had any hesitation about modifying
your own V6.... Don't... You won't be disappointed...!!!
Engine removed and ready for teardown. These
are my beautiful 2 1⁄2 year old twins and they are in training
early for the Commodore of the Year Award in the year 2025.
I took my time during the tear down phase cleaning
and documenting all parts to ensure I had everything organised
and I knew where everything had to go back upon engine assembly.
This was also a time for checking, measurements, assessing overall
engine wear and preparing a parts list and build plan. Fortunately,
the engine was in good order so no real problems at this stage.
The engine was taken apart leaving the crankshaft
in-situ only. No major faults or wear noted with this motor having
travelled an easy 175 000km with a good service record.
- Honing cylinder bores.
An essential aspect of the block preparation. Bore honing and
finishing with the correct cross hatch and surface finish is
critical to ensure proper piston ring bed end and gas sealing.
I elected to keep the honing to a light surface finish with
a shallow cross hatch as the piston rings of the V6 Ecotec are
of a low tension, reduced friction, very narrow design.
- Piston cleaning: This is
one area that was time consuming. Unfortunately, the piston
ring grooves displayed heavy carbon fouling and really did require
some attention. The method I used for cleaning was by means
of snapping the old piston rings in half and using the sharp
edge of the piston ring to scrape out the carbon by pushing
the old ring in and around the ring groove. Soaking the pistons
in parts washer solvent helps to soften the carbon.
- Cleaning: I cannot emphasise
strongly enough the need for meticulous cleaning of all engine
components before assembly. Time spent cleaning and preparing
is critical for professional engine assembly and will eliminate
premature failures upon start up etc. Clean and prepare bores
by means of washing with hot soapy water. Immediately after
cleaning, ensure all cylinder bores and bearing surfaces are
lubricated to prevent surface rust. I fitted new welsh plugs
and painted the engine block prior to assembly.
- Check all ring gaps: Quick
and easy operation to ensure ring gaps are to specification.
Also eliminates the rare possibility of obtaining an incorrect
ring from a mistake in packaging. Simply push each piston ring
squarely down the cylinder bore to a depth 5-15mm and measure
ring gap using feeler gauges. (An inverted piston is ideal for
pushing down and squaring ring)
- Installing pistons and fitting new
big end bearings: Liberally lubricate pistons, rings,
small and big end bearings. I fitted new big end bearings. To
ensure bearing clearances were to specification, I performed
a quick clearance check using flexi gauge.
- Rear main oil seal: The
early V6 Ecotec's suffered from terrible rear main engine oil
seal related oil leaks. To ensure this engine was going to be
oil leak free, I replaced the rear main oil seal and alloy seal
housing as a complete unit. GM Part No: GM-12585248
is the most up to date part number that supersedes every thing
from VS through to VY and now comes complete with a revised
rear main oil seal.
Beautiful isn't it...
The decision for camshaft selection certainly
made for some serious debate. Without question, an engine camshaft
is the most influential component for determining an engines performance
and overall design intent. The build up of this engine certinly
proved this point...!!! My research and consequent final decision
on camshaft selection sent the stress needle well into the redline.
Initially it was my intension to select a combination
camshaft and fixed software package (Computer chip or Memcal)
as this seemed the quick and easy way to go.
Whilst I have absolutely no doubt that camshaft/fixed software
packages provide very credible performance gains and there is
certainly no argument that they will work very well and perhaps
are good value for money, I was simply failing to be convinced
they would give me the performance edge I was looking for from
this build up.
After discussing this issue with many people
and taking several aspects into consideration, I just couldn’t
get my head around the simple fact that “every
engine is different” and who is to say that
what may work in one engine may not work well in mine. For example:
Exhaust design and configuration, variations in compression ratios,
induction system design and modification, overall engine condition
characteristics and even variations in climate will all have an
affect on an engines performance and specific tuning requirements.
What if this engine did not make power or meet
my expectations? Having no further capacity to make adjustments
to the engines tune state would mean I have reached the end of
the road with a poor outcome.
To overcome these concerns I decided to select
a camshaft, from my research, that I felt would deliver the level
of performance I was trying to achieve and install a programmable
ECU (refer to photo 16)
The camshaft chosen was a Crow
Cams Stage 3 grind. Part No: 8531563. This camshaft
is about as big as you can go using a naturally aspirated engine
and running a standard torque converter. To allow precise camshaft
degreeing, I also fitted a Crow 9 Key Way Timing Set.
Part No: CS6VS
Special thanks to Ron Spencer from
Crow Cams for assistance, technical and product
information provided during my camshaft research.
From my experience of rebuilding engines, I
have learnt and cannot place strong enough emphasis on the importance
of camshaft degreeing or timing. Checking camshaft timing takes
a little time however, establishing and setting camshaft position
as per the camshaft grinders specifications can pay enormous dividends
With camshaft replacements, the chances of
the camshaft timing being to specification using standard camshaft
timing components in the straight up and down
position (aligning factory dots) is very rare due to the many
variations between engines and associated components.
For the My Street Car V6,
I used the intake lope lift @ TDC method.
The camshaft degreeing operation certainly resulted in a surprising
outcome. To safe money, I thought I would reuse the original timing
chain and sprockets, pending camshaft timing, as these parts were
still in very good condition. However, upon installation, it was
noted that the camshaft was 6-8 degrees retarded which to say
the least, is considerable. To verify this result, I then installed
the Crow Multi Keyway Timing Chain Sprocket Set at 0 degrees (Timing
marks straight up & down) and the results were exactly the
same. There was now no question that this camshaft was retarded
at factory specification and installation and assembly at this
setting would probably have left me wondering why the engine made
poor power gains. Our camshaft degreeing operations concluded
with the timing sprockets set at the 6 degree advanced marks to
achieve the camshaft card specifications. Whilst this setting
did concern me due to the variation from factory specification,
I did recheck my work several times with the result from each
check being exact every time.
Do not under estimate the power
of cam timing...!!!
As the design intent of My Street Car
is to be a “budget streeter”
my primary objective with the cylinder heads was to recondition
them to as new condition with some basic modifications that would
allow a marginal increase in gas flow.
- 3 angle valve seat cut:
A 3 angle valve seat cut consists of a 2nd & 3rd angle cut
above and below the valve seat angle. These extra angles open
up the valve seat area allowing increased gas flow past the
- Back cut on valves: This
shallow cut removes sharp angles allowing a smooth gas flow
past the valve head.
These are low cost yet proven modifications
that would be a standard requirement in all performance cylinder
Special thanks to Ben at Central
Coast Clutch & Brake (Coast HEADMASTER Division)
for the high quality of workmanship crafted into these cylinder
Nearing completion and awaiting external bolt
on sub assemblies and components.
This photo displays the engines fuel injectors
installed back into the fuel rail and ready for fitment back on
to the engine.
A definite mandatory minimum requirement when
upgrading an engine is to ensure the fuel injectors are serviced
and cleaned. Over looking this aspect of the fuel delivery system
will be your undoing as an engine will not run efficiently, let
alone make any power gain, with blocked fuel injectors.
All fuel injectors in service will over time
slowly become dirty and carbon fouled reducing fuel flow rates
and spray pattern quality. Quite often this gradual deterioration
of the fuel injector goes unnoticed as the driver of a vehicle
becomes accustomed to the slow rate of change. However, eventually
fuel poor fuel economy, significant loss of power, poor idle quality
and in severe cases an engine miss fire will occur as a result
of excessively blocked fuel injectors. In many modern lean running
fuel injected engines, we have found that a fuel flow reduction
of as little as 3% is enough to cause a noticeable deterioration
in vehicle idle quality and drivability. It’s amazing to
see just how an engine comes back to life
after only having a fuel injector service.
Using a quality in tank fuel injector cleaner
at regular intervals and /or the use of Premium Unleaded Petrol
will help maintain a fuel system to a high standard.
Special thanks to Phil Timmins
/ Woy Woy for servicing our fuel injectors.
As we are now chasing more power from of our
engine, a bare minimum requirement was to ensure the fuel system
is running at least to manufactures specifications. A new fuel
pump and fuel filter was fitted to ensure this requirement was
achieved. The fuel pump in a Multi Point Fuel Injected engine
is a high pressure unit (240-260 kPa) that is designed to deliver
a rate of fuel well beyond an engines normal operating requirements.
The standard fuel system in this configuration
has so far delivered the fuel system performance required for
the new engine.
Servicing the throttle body is a simple operation
involving the cleaning and removal of carbon and dirt deposits
that build up in and around throttle plate area and idle control
valve and ports. A clean throttle body will ensure optimum idle
quality and air flow.
This photograph displays the engine assembly
now complete with most external accessories bolted up and ready
for installation back into the vehicle. Check out the Pacemaker
Headers. There is something about a quality set of headers that
demands your attention. This engine is ready for business...!!!
All systems are go, we are ready to hit the
road...!!! This photo also displays the fitment of the Cold
Air Intake (CAI).
A key element in the quest for engine efficiency
and increased power output is improving an engines ability to
breath. A low cost yet highly affective means of achieving this
is with the fitment of a Cold Air Intake
system. The CAI is where the air induction
track begins. The primary function of the CAI is to allow the
maximum possible entry of clean cool air into the engine. It should
be noted that cool air contains more oxygen increasing the density
of the air being consumed by the engine. Cool air with increased
density (high oxygen content) will result in a more complete combustion
process increasing engine efficiency and power output.
Have you ever noticed that your engine sounds
better and has more power when driving on a cold day or even early
in the morning or late in the evening when ambient temperatures
have dropped. This is because the inlet air being drawn into your
motor has more oxygen (high density air charge)
A high quality, professionally developed CAI
also creates a ram air effect as vehicle
speed increases. You can liken this principle to the effects of
holding your hand out the window of a vehicle travelling at speed
or perhaps even the resistance of air you feel when you are riding
a bicycle etc. By harnessing the force of this air flow, by means
of a CAI system, a ram air effect will be created (air now being
pushed). Directing this ram air into the engine via the engine
induction system will significantly increase the engines breathing
For My Street Car, I used
the CAI system that is factory fitted to the V6 Super
Charged model. These are Holden Original Equipment
components and are a direct fit to the standard naturally aspirated
V6 model. Installation takes only 15-20 minutes. To compliment
the increased breathing capacity of the CAI and modified motor,
I also installed a K&N high flow air filter.
Ducting assembly (Intake): PN: GM 92053314
Inlet assembly (Intermediate): PN: GM 92053315
Body assembly (lower air filter housing): PN: GM 92053006
These parts are available from any Holden Dealership
and are very reasonably priced.
The exhaust is one area of the engine build
up phase where I received a good response from various Exhaust
Specialists and Manufactures that I made contact with when conducting
some product research prior to commencing engine teardown. I feel
this fact alone just goes to prove there is strong confidence
by after market Performance Exhaust Manufactures that no matter
what level of modifications are being carried out, that there
is significant power gains to be made with exhaust modification.
It has always been generally accepted that worthwhile and noticeable
gains in engine performance are possible when upgrading an exhaust
as a single modification, even on standard motors.
It should be noted that there is more to exhausts
than most of us realise. In fact, exhaust tuning itself is a real
science. There are so many factors that should be taken into consideration
when designing or selecting an exhaust for a particular application.
Engine displacement, level of modifications and intended usage
are just some serious factors to be considered. An interesting
point is that bigger is not always better. Power can actually
be lost by over exhausting an engine
(piping diameter to large) that does not have a level of modification
to match. The vacuum effect (scavenging) of the header and exhaust
will be reduced with large diameter pipes dissipating heat at
an increased rate which creates a denser/heavier gas that requires
more effort to push due to the cooler gas's increased resistance
- Pacemaker Headers. Part Number:
PH 5039: Whilst I honestly believe there are several
quality headers in the market place, I was particuly impressed
with the Pacemaker overall design and pipe configuration. The
Pacemaker Headers are of a fully tuned design incorparating
equal length piping. The quality and design of the Pacemaker
product is exceptional and I felt strongly that this product
has been researched and designed for actual performance gains
not just as a standard replacement part.
- 2 1⁄2 inch Hi flow catalytic
converter: Factory fitted Y Pipe
retained and modified to allow connection to headers and high
flow catalytic converter.
- 2 1⁄2 inch single system:
Locally fabricated and incorporates both a main muffler and
rear resonator that are of a straight through design. (No power
robbing reverse flowing baffles)
Making a decision on the configuration of exhaust
that I should use wasn't an easy choice. As the level of modifications
for my engine were becoming more considerable than initially planned,
it could be argued that a twin catalytic exhaust would have been
more suited and possibly resulted in a slightly higher power output.
As this is a budget type build, I decided to trial the single
system to keep costs down. Having said that, I am on a learning
curve and a lot of what I am doing will be learnt simply from
trial and error. As it turns out, the engine is performing well
and making very credible power. Would a twin cat exhaust have
provided more power...??? I'd love to find out one day...!!!
Whilst I received great feedback from several
persons, I would like to make a special thanks to Mike Richter
who represents Pacemaker Headers as a Partner and is involved
with Product Research and Design. The level of information received
from Mike included a 3 page product information bulletin and technical
guide that was loaded with interesting and informative information.
This information was a great read and of great assistance with
several aspects of this build up including engine design theory,
modification considerations and consequent component selection.
Thanks also to David Creman from
Carline Mufflers in Gosford for assisting with the
exhaust design and for the workmanship crafted into the exhaust
As mentioned with notes for Photo 5, it initially
was my intension to install a combination camshaft/fixed software
package. As per this information, I was reluctant to deviate from
this plan. Fortunately, I feel I am able look back and believe
I made the right decision.
Tuning this engine with the Haltech ECU has
been the most fun I have ever had tuning an engine. No drilling
out jets or making manual timing adjustments etc. All tuning is
conducted from the driver’s seat, via a laptop computer.
For this application, I decided to use the
Haltech Interceptor Factory Piggy Back ECU.
This Haltech unit is fitted in parallel with the vehicles factory
ECU. The great advantage of this set up is that by retaining the
factory ECU, all factory engine settings are retained with the
capacity now to make fine adjustments as required. It should be
appreciated that the factory tuned ECU has been the result of
literally hundreds of hours of development by expert personal
from the vehicle manufacture. The final validated settings are
no mistake and are locked in to provide optimum performance and
economy for a particular load setting and application. Retaining
the factory ECU means you also retain the vehicles valuable factory
settings that provide good drivability and economy at light loads
However, whilst the factory ECU will compensate
for some change, there is a point where tuning intervention is
required to optimise the performance modifications carried and
mechanical deviation from factory design.
This is where the Haltech is brilliant.
You really are in command with your tuning, having the scope to
make unlimited changes. The software package is fantastic and
the front screen a work of art. I am blown away with this product,
its operation and tuning power.
Upon start up with factory settings, the car
actually ran quite well. It wasn't until I started making on road
adjustments that I realised that there was now so much more potential.
On the dyno, the first run resulted in approx 125kw. After just
2 x adjustments we were into the 130kw zone. Having the capacity
to make changes gives you full control of your tuning options.
The outcome is now in your hands...!!!
I would like to make special thanks to Scott
Hilzinger and Paul Davis from Haltech Engine Management Systems
for the product information, recommendations, technical information
and general assistance provided whilst I was searching this option.
Well, its time now to rest the
engine for while and concentrate on the Chassis Dynamics development.