At the end of the tunnel....

...there is light...

 We got a little sidetracked while waiting for parts and dealing with the drama sometimes this place goes under,  needless to say, morale was a bit low this week.

But there is no need for crying over spilled milk, a set back can only make us stronger.

So let's get back to the fun side of Axiom,  the reinvention of this 74 former Targa.

 The 3.1 litre is in and now it's time for some fabrication, the intercoolers will be placed under the quarter panels, with custom plumbing to the 70mm throttle body,  twin oil-less turbos attached with V band and custom exhaust with a center outlet.

 Pro 128 ECU with all the goodies in it, capable of  using flex fuel without changing maps,  this is how the big boys play....



I know it is taking longer than anticipated,  but I can see the light now.

Get a grip...

......on the ground, that is.  It seems like our oil-less turbo make more power than we anticipated.

Basically a stock turbo with a couple of better items:
adjustable TurboSmart BoV, Boost gauge and manual controllers. and Waste gate.  An oil-less turbo from CompTurbo, and Custom headers made by us.
 and when I new clutch was needed,  we asked what kind........something not too radical, the horsepower is not that high.

But with an adjustable boost controller, pushing buttons can be tempting and once you past the 1 bar mark, the new clutch began to slip. 

This happened Friday........and we promised the client he can drive it on Monday.....

Some people have 3 day weekend, we sometimes have no weekend. 

We took a little trip to the Inland Empire and had the boys and girls of Clutch Masters custom made a disk and pressure plate.  they put a rush in and the boss had to pick it up late on Saturday.

In the meantime, back at the cave.....Gerardo and I got things ready, with the engine on the ground and transmission off, we waited.........traffic and time got the best of everything........I guess our Sunday just got cancelled.

But on Sunday morning, we put petal to the metal and by 11:30 the wheels hugged the ground without letting go.

When it's all .....LOBE....

 I remember when I was a kid in school, if I had homework, I would have to convince some friends to come with me to the library and then try to get there before other 50 kids with the same assignment get the one book...........decades later, there is Wikipedia.  So, lets talk cams: if your heads need more air to create more power, the valves' timing of the duration of the lift, has something to do with it, it's a "lobe" affair.

History

An early cam was built into Hellenistic water-driven automata from the 3rd century BC. The camshaft was later described in Iraq (Mesopotamia) by Al-Jazari in 1206. He employed it as part of his automata, water-raising machines, and water clocks such as the castle clock. The cam and camshaft later appeared in European mechanisms from at least the 14th century, or possibly earlier.

Uses

In internal combustion engines with pistons, the camshaft is used to operate poppet valves. It then consists of a cylindrical rod running the length of the cylinder bank with a number of oblong lobes protruding from it, one for each valve. The cams force the valves open by pressing on the valve, or on some intermediate mechanism as they rotate.

Automotive

Material

Camshafts can be made out of several different types of material. These include:

Chilled iron castings: this is a good choice for high volume production. A chilled iron camshaft has a resistance against wear because the camshaft lobes have been chilled

Billet Steel: When a high quality camshaft is required, engine builders and camshaft manufacturers choose to make the camshaft from steel billet. This method is also used for low volume production. This is a much more time consuming process, and is generally more expensive than other methods. However the finished product is far superior.

Timing

The relationship between the rotation of the camshaft and the rotation of the crankshaft is of critical importance. Since the valves control the flow of air/fuel mixture intake and exhaust gases, they must be opened and closed at the appropriate time during the stroke of the piston. For this reason, the camshaft is connected to the crankshaft. In a two-stroke engine that uses a camshaft, each valve is opened once for each rotation of the crankshaft; in these engines, the camshaft rotates at the same rate as the crankshaft. In a four-stroke engine, the valves are opened only half as often; thus, two full rotations of the crankshaft occur for each rotation of the camshaft.

The timing of the camshaft can be advanced to produce better low end torque or it can be retarded to produce better high end torque.

Duration

Duration is the number of crankshaft degrees of engine rotation during which the valve is off the seat. As a generality, greater duration results in more horsepower. The RPM at which peak horsepower occurs is typically increased as duration increases at the expense of lower rpm efficiency (torque).

Duration can often be confusing because manufacturers may select any lift point to advertise a camshaft's duration and sometimes will manipulate these numbers. The power and idle characteristics of a camshaft rated at .006" will be much different than one rated the same at .002".

Many performance engine builders gauge a race profile's aggressiveness by looking at the duration at .020", .050" and .200". The .020" number determines how responsive the motor will be and how much low end torque the motor will make. The .050" number is used to estimate where peak power will occur, and the .200" number gives an estimate of the power potential.

A secondary effect of increase duration is increasing overlap, which is the number of crankshaft degrees during which both intake and exhaust valves are off their seats. It is overlap which most affects idle quality, inasmuch as the "blow-through" of the intake charge which occurs during overlap reduces engine efficiency, and is greatest during low RPM operation. In reality, increasing a camshaft's duration typically increases the overlap event, unless one spreads lobe centers between intake and exhaust valve lobe profiles.

Lift

The camshaft "lift" is the resultant net rise of the valve from its seat. The further the valve rises from its seat the more airflow can be realized, which is generally more beneficial. Greater lift has some limitations. Firstly, the lift is limited by the increased proximity of the valve head to the piston crown and secondly greater effort is required to move the valve's springs to higher state of compression. Increased lift can also be limited by lobe clearance in the cylinder head construction, so higher lobes may not necessarily clear the framework of the cylinder head casing. Higher valve lift can have the same effect as increased duration where valve overlap is less desirable.

Higher lift allows accurate timing of airflow; although even by allowing a larger volume of air to pass in the relatively larger opening, the brevity of the typical duration with a higher lift cam results in less airflow than with a cam with lower lift but more duration, all else being equal. On forced induction motors this higher lift could yield better results than longer duration, particularly on the intake side. Notably though, higher lift has more potential problems than increased duration, in particular as valve train rpm rises which can result in more inefficient running or loss or torque.

Cams that have too high a resultant valve lift, and at high rpm, can result in what is called "valve bounce", where the valve spring tension is insufficient to keep the valve following the cam at its apex. This could also be as a result of a very steep rise of the lobe and short duration, where the valve is effectively shot off the end of the cam rather than have the valve follow the cams’ profile. This is typically what happens on a motor over rev. This is an occasion where the engine rpm exceeds the engine maximum design speed. The valve train is typically the limiting factor in determining the maximum rpm the engine can maintain either for a prolonged period or temporarily. Sometimes an over rev can cause engine failure where the valve stems become bent as a result of colliding with the piston crowns.

Boost me up Scotty

Boost controller....can we talk ??
Ok, so as far as I know, forced induction have been around since...well, according to history, since the bootlegging days;  In those days when the jig was up and the law had you pegged, the car had to be ready to go, go, go and the driver had to know how to handle that horsepower.

Many steps have been taken to improve non aspirated horsepower, you name it, it's been done.  From fuel enrichment tricks to tailored boost.

Boost, give me more boost !!!
It is almost like a drug......

Manual boost controllers have made this task a little easier, rather than to physically take the waste gate apart to replace the spring, a touch of some buttons is needed to accomplish that. 

 After using many different units, we came to the conclusion that the TurboSmart gauge and controller is the best way to feed the beast.  Turbo chargers are not smart, they will create boost until your cylinders look like little astrays,  the e-bost unit will become the brain.

 From:  http://www.turbosmartonline.com/index.php?id=42

All Turbosmart e-Boost Controllers feature our exclusive adjustable gate pressure feature which minimizes wastegate creep and can improve turbo response by up to 1000 rpm earlier in the rev range – this means that you can increase the performance and response from your engine without even raising the maximum boost level. e-Boost controllers allow the user to control 3 different aspects of the boost curve; the maximum boost pressure (set point), the spool up rate of the turbocharger (gate pressure) and the reaction time of the controller (sensitivity).

Boost Levels: up to 6 levels of boost.
Boost on Demand: provides instant overtaking power at your fingertips
Gear-based Mapping: set a different boost for each gear!
Adjustable Boost Levels: program boost against TIME or RPM.
Aux Output: fully programmable; controls water spray, methanol or nitrous injection.
RPM Compensation: eliminates boost drop-off at high RPM.
Peak Hold/Max Boost Recall: monitors boost and RPM.
Gate Pressure: eliminates wastegate creep.
Overboost Shutdown: provides added protection for your engine .
Display: programmable, can be configured to KPA, Bar or PSI.
Auto Dimming: with backlit buttons for hassle free navigation.
Aceessories: dash and roll cage mounting kits, shift/warning lights and a full range of spares.

Special guest

The National Geographic channel aired their episode of Break it Down, Porsche in Pieces last night, and this black Pearl made an appearance, since then we have been asked to elaborate in this build.

 It started as a 1975 S, but has been through the carousel of changes, first the 2.7 liter engine was replaced with a 3.2 first, while the boss was building the twin turbo twin plugged that takes him around town these days.

Having invested in the fabrication of a special engine lid, it would have been shame to lose it and make room for the intercooler, instead, let's put individual coolers under the quarter panels.

The coolers get their fresh air through the custom made vents  added to the body.
A especially designed muffler keeps his neighbors in good standing, but manual boost controllers can sometimes let its presence known.
Coil overs in all corners, strut support bar and 28mm sway bars keep it close to the ground while making very tight corners.

 The AC brackets and fuel rails were modified to allow room for the retractable 996 wing to be operational.  AC fully charge keeps the passengers of the two baby seats in comfort, a roll bar keeps them protected.

The engine is a 3.1 liter twin turbo, twin plugged, flame ringed, ported and polished heads fed by two motorsports fuel pumps and allowed to breath by TurboSmart waste gates and blow off valves

There have been many changes since his appearance on TV, and I am sure there will be more.

Fuel Pressure

I am often asked to do a more technical post, the truth is that I sometimes don't have all the facts to do so, but since we recently became a TurboSmart dealer, here is one of their products, one of  which we think it's a very important part of performance.

How does an FPR work?

What is a fuel pressure regulator?
A fuel pressure regulator (FPR) is a device which controls the pressure of fuel supplied to the fuel injectors on an engine.

How does a Turbosmart FPR work?
A Turbosmart FPR works by bleeding off a portion of the fuel flow to the injectors from the fuel pump to control the fuel pressure.
Fuel is pumped from the fuel tank to the fuel rail by the fuel pump. The FPR is normally mounted after the fuel rail to ensure that the fuel rail has priority in fuel flow. The valve in the FPR controls the amount of fuel that is bled from the fuel rail by opening an outlet port to allow fuel to flow back into the fuel tank.
All injectors need a pressure difference between the inlet and the outlet of the injector to spray fuel into the combustion chamber. This is called the base pressure. The base pressure is adjusted on all Turbosmart FPR’s via the adjustment screw to suit the injectors and fuel pump system you are using.
The adjustment screw pushes down on a spring which applies a force onto the valve. When the pressure inside the bottom chamber of the FPR exerts a high enough force on the valve to overcome the spring force and lift the valve off its seat, it allows fuel to flow through the outlet port effectively controlling the fuel pressure in the fuel rail.

Since the outlet of the injector is exposed to manifold vacuum/pressure which varies depending on throttle movement, but the flow of fuel from the fuel pump is constant, the valve needs a reference to continuously change the amount of fuel bled to maintain constant fuel pressure to the injectors. In addition to the spring force acting on the valve, a vacuum/boost signal also applies a force onto the valve so that the valve is always maintaining a constant pressure difference between the inlet and outlet of the injector.  For more on TurboSmart you can visit:  http://www.turbosmartonline.com/