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camshaft design

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    camshaft design

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    Camshaft Design. Camshaft design today is an extremely complex process employing the use of computers in every phase of design analysis and testing not to mention the years of experience required to make these phases become reality. As complex as it is however, camshaft design, in its simplest form, may be broken down into two segments.
    The first segment involves lobe placement on the camshaft. This establishes the very critical valve train event timing in relation to piston and crankshaft positions. It also establishes the displacement or separation of the intake lobe in relation to the exhaust. This placement is very critical and must be exactly the same for each cylinder. Lobe placement is one segment of the camshaft design experience that relies heavily on the designer's experience. As you already know, you may advance or retard the camshaft in the engine, but altering the displacement requires a new camshaft.
    The second segment involves designing the lobe and clearance ramp profiles. By far, this is the most critical and difficult segment of camshaft design. In today's race engines you must develop a lobe profile that is aggressive enough to produce the desired rate of lift yet smooth enough to avoid new valve train problems. You must walk a very thin line here to take advantage of the attainable high R.P.M. power available with today's cylinder head designs, yet not lose it all to stress, deflection and failure of the valve train. More recently, significant power gains have been found through several new approaches to clearance ramp profiles.
    Obviously the computer has become a most valuable tool in all design applications from economy camshafts to the most sophisticated of race designs. But the computers and all the programs would be useless without the experience to back up a total design effort. It's the optimum blending of engineering, years of design experience, technology and communication that offers the Cam Techniques competitive edge.

    .

    Camshaft Design. Camshaft design today is an extremely complex process employing the use of computers in every phase of design analysis and testing not to mention the years of experience required to make these phases become reality. As complex as it is however, camshaft design, in its simplest form, may be broken down into two segments.
    The first segment involves lobe placement on the camshaft. This establishes the very critical valve train event timing in relation to piston and crankshaft positions. It also establishes the displacement or separation of the intake lobe in relation to the exhaust. This placement is very critical and must be exactly the same for each cylinder. Lobe placement is one segment of the camshaft design experience that relies heavily on the designer's experience. As you already know, you may advance or retard the camshaft in the engine, but altering the displacement requires a new camshaft.
    The second segment involves designing the lobe and clearance ramp profiles. By far, this is the most critical and difficult segment of camshaft design. In today's race engines you must develop a lobe profile that is aggressive enough to produce the desired rate of lift yet smooth enough to avoid new valve train problems. You must walk a very thin line here to take advantage of the attainable high R.P.M. power available with today's cylinder head designs, yet not lose it all to stress, deflection and failure of the valve train. More recently, significant power gains have been found through several new approaches to clearance ramp profiles.
    Obviously the computer has become a most valuable tool in all design applications from economy camshafts to the most sophisticated of race designs. But the computers and all the programs would be useless without the experience to back up a total design effort. It's the optimum blending of engineering, years of design experience, technology and communication that offers the Cam Techniques competitive edge.

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    For some of us, camshafts are a lot like marriage-we understand the concept but cannot fathom exactly how to make it work. For example, why is duration always measured in crankshaft degrees? And why do you not begin measuring duration until 0.050 inch of lift? Or why do camshaft manufacturers grind a cam advanced? What does the lobe separation angle have to do with performance? And why does advancing the camshaft seem to help low-end torque?

    The science behind camshaft design is as advanced as anything in a race car, so most of us-including experienced engine builders-depend on the manufacturer to help spec the right cam for a particular engine package. Still, there is a science that controls every part of the design of your camshaft, and understanding why different parts of the cam are designed a particular way can help you determine what works best for your needs.

    Lobe Design
    Of all the different parts of the cam, most are relatively straightforward (e.g., the journals and distributor gear). The cam lobes, one for each valve, contain all the variables. The cam lobes control not only total lift and when the valves open and close, but also valve speed, acceleration, overlap, and even how much cylinder pressure is developed at speed. There are a few parts of the lobe design critical to achieving this.

    A cam chart like this can tell you just about everything you need to know about a cam. This is a typical design used in the Busch Series. The red line shows where the cam has the exhaust valve positioned in terms of lift for every degree of the crank's movement. The blue line is for the intake. Where the two lines intersect is valve overlap. The circles at the bottom mark lift at 0.050 inch. Courtesy of Comp Cams
    Base Circle is the term for the backside of the lobe. When the lifter is on the base circle of the lobe, the valve should be closed. It is also commonly called the heel of the lobe. The size of the base circle is important in relationship to the cam's lift. A smaller base circle allows more lobe lift, but it can also allow the camshaft to flex and throw off the timing events.

    Ramps are the parts of the lobe where the lifter is either moved up or allowed to drop. Every lobe has two ramps-an opening ramp and a closing ramp. In performance camshafts, the curve of the ramps changes several times, which is a tool the cam designer uses to fine-tune the speed and acceleration of the lifter.

    An asymmetrical lobe refers to opening and closing ramps that are not identical. In order to maximize both valve speed and control, the lifter must be raised in a different manner from which it is lowered. For example, in performance applications the valve is generally opened as quickly as possible, but the speed of the valve slows significantly as it nears maximum lift to keep it from lofting. But on the closing side, the valve must be seated relatively gently to keep it from bouncing. An asymmetrical lobe design allows this.

    The nose of the lobe marks the area where the valve is fully opened. The highest point of lift is the lobe's centerline. The intake centerline is measured as crankshaft degrees after top dead center (TDC). The exhaust centerline is expressed as the number of degrees of the crankshaft's position before TDC. Incidentally, a cam's position is always measured relative to the crankshaft's position because that tells you where the piston is and which stroke it is on (intake, compression, power, or exhaust).

    Lobe lift is the amount the cam lobe raises the lifter. It isn't the same as valve lift because the rocker arm is a lever that multiplies the amount of lobe lift to get the final valve lift. The lobe lift is equal to the diameter of the lobe at the centerline minus the diameter of the base circle.

    Many cams are ground with 4 degrees of advance built-in, but that isn't always the case with race cams. You can experiment by advancing and retarding the camshaft a couple of degrees with special adjustable timing sets to see if the changes give you any benefit on the racetrack.
    Tuning with Lobe Separation
    Obviously, the primary job of the camshaft is to control the timing of the intake and exhaust valve events. This is done with separate intake and exhaust lobes. The relationship of these lobes to each other is called lobe separation. Lobe separation is measured in degrees between the peak of the exhaust lobe (maximum valve lift) and the peak of the intake lobe. Essentially, it is half the angle in crankshaft degrees of rotation between peak exhaust valve lift and peak intake valve lift. If the duration remains the same, increasing the lobe separation angle decreases overlap, while decreasing it does the opposite.

    "Typically, if all other factors are kept constant, widening the lobe separation produces a wider, flatter torque curve that holds better at higher rpm but can sometimes cause a lazy throttle response," explains Billy Godbold, a camshaft designer at Comp Cams. "Tightening the separation generally produces the opposite effect-more mid-range torque and a faster revving engine, but with a tighter power range."

    There are other reasons to change lobe separation to influence engine performance. For example, if you are running a long rod package and keep the stroke the same, you will dwell the piston near TDC longer. To maintain similar overlap characteristics, you may need to open up the lobe separation and shorten the duration.

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    Camshaft Innovations is pleased to say that we do not compromise quality just to make a sale. Quality is CI’s #1 focus. The CI cam cores are hand chosen for each application. CI makes sure that the lobe designed for your specific application will fit perfectly on the cam core chose allowing for the most durable . All of our camshafts are completely ground on CNC machines and not cam lathes. All roller camshafts (Hydraulic or Mechanical) are ground on the finest steel billet cam cores available. If the customer requests, a hydraulic roller may be done on a SADI (ductile iron) core if the cam designed will fit on that style of core and Cam Master Jay agrees that style of cam will work adequately. CI will not sell an inferior product just to price match. If you are price shopper, then CI is more than likely not for you. However, if quality and accuracy are important to you, then you’ll get what you pay for at Camshaft Innovations !
    Camshaft Innovations also provides each and every camshaft with a Cam Doctor report performed on an Audie Pro Plus fixture. Because CI does spend such time worrying about quality, CI also wants to insure accuracy. Once the camshaft has been on our state of the art Cam Doctor, if it does not meet our stringent quality control program, that camshaft will get “tuned up” at zero cost to the end user. This ensures that when you open your camshaft from CI, the quality and accuracy are second to none. This also allows CI to provide you with a camshaft that does not require a degree wheel to install your camshaft accurately. Cam Master Jay will be happy to discuss this with you upon receipt of your order. Even a novice cam installer will be amazed at the ease of installation, while the seasoned engine builder will be upset that he has never used CI before.
    Camshaft Innovations also lets results speak for themselves. CI takes great pride in assisting each customer with other “tips” that will allow the customer awesome results. CI sells performance. No matter what your application is, CI provides results.
    For pricing and an explanation of the CI line of camshafts, click on the type of cam you are interested in:
    Hydraulic Flat Tappet
    Hydraulic Roller
    Solid Flat Tappet
    Mechanical Roller

    To contact Cam Master Jay, please call 734.730.2574 from 9am-7pm or e-mail him at [email protected]


    ***No Refunds***No Exchanges***

    Home · About CI · Customers · CI Projects · Feature Tech Tips · LinksCamshafts · Cylinder Heads · Other Products · CI Build Sheet · Calculators
    © 2006 Camshaft Innovations. All rights reserved.

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    Design Consequences of Digital Camshaftsby L. Van Warren© 1998 L. Van Warren • All Rights Reserved
    Introduction
    A digital camshaft is an electronically controlled valve modulation device that replaces a conventional mechanical camshaft. A digital camshaft has several advantages over a conventional camshaft. One advantage is that the lobe shape of the digital cam can be varied as a function of engine speed and combustion conditions. This is difficult to accomplish with a conventional mechanical camshaft. A second advantage is that individual lobe offset (valve timing) can be varied in relation to ignition timing and crank position in real time. A third advantage is a possible reduction in power dissipation compared to mechanical camshafts. A disadvantage is an increase in system complexity. Because this complexity is electronic rather than mechanical, it is more easily managed. Note that in the general case lobe offset is a subset of lobe shape. Open issues are those of how to factor the logic and power activation capability, on a per lobe, per cylinder or per camshaft basis. A per cylinder approach is proposed here since any chipware developed as part of the prototyping activity could be instanced for different engine configurations without incurring significant additional development costs.
    For the purposes of this analysis, it will be assumed that the successful modulation of valve position via a digitally controlled, position encoding, solenoidal system is possible. If successful this approach is applicable to all four cycle internal combustion engines. We will now ask a set of questions whose purpose is to assess an appropriate first context for this technology. Prototyping of this technology is best done in a single cylinder context. Per cylinder chipware can be reused.
    On a more general line of reasoning it is interesting to consider how much this technology - if it were deployed - could influence engine design. Consider the a design variable as elementary as the optimal number of cylinders:
    Question 1: If we employ a digital camshaft, and if the frictional losses of that digital camshaft are significantly less than those of a conventional camshaft, how many cylinders should the engine have? This leads to a second question.
    Question 2: To first order, how do internal frictional losses vary as the number of cylinders is increased from one cylinder to more than one?
    Answer: For a "square" engine where bore equals stroke, we seek a relation between contact area (friction) and enclosed volume (power) as the number of cylinders increases. We will assume that, in the presence of a digital camshaft, cylinder wall losses account for the majority of the internal frictional losses in an internal combustion engine. The result is: "wall frictional losses grow as the cube root of the number of cylinders"This enjoyable proof of this is left to the reader as an exercise. The reader pressed for time can click on the link above to see my version of the answer. The consequence of this wonderful result is that an eight cylinder engine will have approximately twice the frictional losses of a single cylinder engine of equivalent displacement (two cubed is eight). A twenty seven cylinder engine of equivalent displacement will have three times the frictional losses of that same single cylinder engine (three cubed is twenty seven). A plot of these losses is shown below:

    If frictional wall contact losses were a principal design driver, then all engines would have only one cylinder. This is not the case. There is also the issue of engine smoothness. We know that as we increase the number of cylinders in an internal combustion engine, the engine runs more smoothly. This depends on a number of design variables, flat opposed configurations, V configurations and inline configurations and firing order. We will defer evaluating these design variables for the moment and focus on cylinder count alone.
    Question 3: To first order, how does engine smoothness vary as the number of cylinders is increases from one to more than one. The result is: "engine smoothness grows linearly as the number of cylinders increases"Now we can make an assessment of how many cylinders gives us the most smoothness with the least frictional losses. A plot of this simplified smoothness rule looks like:

    Not surprisingly, engine smoothness continues to increase as the number of cylinders increases.

    Question 4: Quality per Unit Cost. If we take the engineering virtue of smoothness, (large values are good) and multiply it by the reciprocal of losses (large values are good) we can define a notion of quality. We can then ask at how quality varies with cost, where the cost metric is engine complexity. Engine complexity is measured as parts count where each part has some characteristic MTBF - Mean Time Before Failure. A plot of quality versus cost looks like:
    From this plot we see that an eight cylinder engine is twice as expensive to field as a one cylinder engine all things being equal, assuming our simplifying assumptions are met.
    Question 5: Is there a weight advantage that accrues from having more or fewer cylinders. That is, which is lighter for a given displacement, a single cylinder engine or one with many cylinders? The answer is, to first order: "minimum weight does not change as the number of cylinders changes."The proof of this is also fascinating.

    Valve Aspects
    With this kind of approach the compression forces on the valve stem are presumably less than with a conventional camshaft. There is a necessity to keep heat from being transferred to the solenoid or position encoder sections. Magnetic materials with high flux density tend to be quite temperature sensitive and must be kept below their demagnetization or "Curie" point. Optical position encoders can be more robust, but their semiconductors must be appropriately protected. The diagrams above show this being accomplished via both a thermal standoff (distance) and cooling air (convection). The lower axial forces and cooler running requirements suggests a hollow stem of a possibly non-metallic reinforced ceramic material. Engine RPM is typically limited by valve train performance, e.g. "valve float". This mandates as light a valve as possible. Since maximum excursion frequency is limited by the mass of the valve there is an additional driver for keeping the valve as light as possible. A reinforced or directionally solidified ceramic valve with a metallic seal might serve as an appropriate alternative. Since the heaviest component of the digital camshaft lobe is a rare earth magnet, it might be possible to have the digital camshaft and valve train weigh less than conventional camshafts and valve trains resulting in a saving of weight. Heat dissipation requirements suggest that the footprint of the system will be about the same size or slightly larger than conventional valve trains.
    Solenoid Activation
    Driving the valves is very similar to driving a conventional loudspeaker with a couple of exceptions. Although the signal is bipolar, the excursion of the valve is limited to one direction only. If we take positive solenoid current to open the valve, then negative solenoid current can be used to hold the exhaust valve closed during the intake stroke and the intake valve closed during the exhaust stroke. A return spring is pictured in the diagram to augment this. This spring could be much weaker than conventional valve springs since the solenoid is available to accelerate closing the valve. Signaling the solenoid takes place via a solid state audio frequency amplifier. Robust FET power transistors and filters will be required to handle the demands of what is in effect a linear motor with a collapsing magnetic field. Valve opening and closing frequencies are in the low audio spectrum, thus it may be possible to modify off the shelf hardware for prototyping.
    Discussion
    There are several factors not accounted for in this elementary analysis. One of these factors is cylinder configuration. Flat, opposed, inline, and V configurations have all been around for years. What has not influenced engine design is modular construction technologies that a direct consequence of information theory. Information theory teaches that copies of identical subsystems are desirable from a fabrication, assembly and servicing point of view. This in itself is new to an industrial society. Eli Whitney introduced the concept of interchangeable parts over a century ago. However, the degree to which this concept can be implemented is controlled by the degree to which essential engine services are centralized. Examples of centralized services are carburetors, ignition coils, and distributors. These have all been eliminated to various degrees. The introduction of an digital or electronic camshaft frees the engine designer to not merely make the pistons, valves, fuel injectors and spark plugs identical, but the cylinders, cooling, oil, crankshaft and camshaft as well. Increasing the modularity of engine systems creates a greater opportunity for recycling, rapid repair and variable engine sizing with a fixed inventory of parts. Further as the components are improved and optimized these improvements become simultaneously available to all parts of the system simultaneously. Conclusion
    We can now create a simple abstract model of the system for the purposes of blocking out our engineering tasks. Prototyping on a single cylinder system and using a modular construction paradigm at the cylinder, crankshaft and digital camshaft may open new possibilities. - LVW

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    مقالة منقولة((Camshaft Basics))

    Taking The Mystery Out Of How Camshafts Work
    By Jeff Smith
    photographer: Jeff Smith












    The camshaft is unquestionably the most complex component in the internal combustion engine. The good news is that despite its complexity, the terminology can be easily understood if we digest it in bite-sized chunks. The camshaft's role in the engine is to control the valve timing, ensuring that the intake valves open at the proper time to feed air and fuel into the engine. The second part of this operation is to give the exhaust sufficient time to escape out of the combustion space before the whole process starts over again. It's the size, shape, and placement of all those eccentric bumps on the camshaft that make it all happen.
    Brutal Basics
    For the purposes of our discussion, we'll deal strictly with the small- and big-block Chevy and with pushrod engines in general, but these basics apply to any four-stroke engine from a Briggs & Stratton to a Formula 1 screamer. In pushrod V-8 engines, the camshaft is located directly above the crankshaft and is driven at one-half engine speed by a chain-and-gear assembly located behind the timing chain cover at the front of the engine.
    The camshaft rides on five main journals and operates the valves by using 16 eccentric lobes accurately machined into the camshaft to time the opening and closing of the valves. These lobes move lifters that are positioned in the block in the lifter valley. Pushrods then actuate rocker arms up and down. The rocker arms use a leverage ratio to increase the lift of the cam lobe. Stock rocker ratios for the small-block Chevy are 1.5:1, while the big-block uses 1.7:1. Performance aftermarket rocker arms amplify this ratio from 0.10 to as much as 0.30 or more.
    There are two basic styles of camshafts: flat- and roller-tappet. Flat-tappet cams are more popular and less expensive and use a tappet, or lifter, with what appears to be a flat follower. In reality, there is a slight convex curvature to this surface, which spins the lifter in its bore, preventing excessive wear.
    Flat-tappet camshafts are generally constructed of cast iron and are induction-hardened to prevent wear. Roller camshafts use a roller follower that, as the name implies, allows the follower to roll over the face of the cam lobe. The reduction in friction is minimal, but the design of the roller tappet does allow a far more aggressive lift curve with the same amount of duration.
    With both flat-tappet and roller cams, the engine builder also has the option to specify either a hydraulic or solid lifter design. Solid tappets are the simplest to understand since they represent a solid link between the camshaft follower and the rocker arm. Solid lifters require a clearance, or lash, that's measured between the rocker arm and the valve tip. A hydraulic lifter does not require this lash because it uses a small piston located inside the lifter to hydraulically compensate for heat expansion, maintaining a zero lash at the valve stem tip that does not require adjustment.
    Cam Specifics
    Now that we know what the cam is and where it resides in the engine, the best thing to do next is learn some basic camshaft terminology. We'll start by looking at the basic camshaft lobe and its various characteristics. A camshaft lobe is an eccentric that converts rotating motion into linear (up and down) movement. To do this, a lobe, or bump, is created from a true circle known as the base circle of the cam—also known as the heel. As the lobe rotates, the lifter follows the rise of the lobe, which moves the lifter upward. The maximum amount of rise is known as lobe lift. This is multiplied by the rocker arm ratio to create valve lift. So if we had a lobe lift of 0.300 inch with a rocker ratio of 1.5:1, then valve lift would be 0.450 inch. Increase the rocker ratio to 1.6:1 and the valve lift jumps to 0.480 inch.
    The maximum lift point on the cam is called the nose, while the inclined areas leading up to and away from the nose are called the ramps. For solid lifter camshafts, a small clearance ramp is included on the opening side ramp to gently remove the lash before the cam begins to open the valve. This prevents valvetrain abuse.
    At some point on the opening ramp, the lobe begins to create lift. Depending upon the company's definition of "advertised duration," some point on the lift curve of the opening ramp is used to determine where cam lobe duration is measured. For hydraulic-tappet camshafts, some companies use 0.006 inch of tappet lift, while others use 0.010 inch on the opening and closing points of the lobe as the start and stop points for measuring advertised duration. Camshaft duration numbers are always expressed in crankshaft degrees.
    Since there are so many different measuring points for advertised duration, a common measuring point became necessary so cams from different companies could be accurately compared. The industry established 0.050 inch of tappet lift as that standard measuring point. Keep in mind that this shortens the duration figure considerably from the advertised numbers. For example, an Isky 270 Megacam offers 270 degrees of advertised duration, but the 0.050-inch tappet-lift duration figures measure 221 degrees.
    At this point, it's worth looking into the effect of duration on engine power. Stock camshafts offer relatively short duration and low lift numbers since the factory is after a crisp, smooth idle and excellent part-throttle operation. Most OEM cams are in the neighborhood of 190 degrees of duration at 0.050-inch tappet lift with valve lift around 0.400 inch. If we increase duration, the intake valve is now open for a longer period of time during the induction cycle. This added duration tends to affect engine power by decreasing idle vacuum and shifting the power curve to a higher rpm. This reduces low-speed throttle response and power while increasing power at the higher engine speeds. Too much duration, especially in stock-type engines, will kill power everywhere, and you will end up with an engine that is extremely lazy.
    In the old days of camshaft design, most cams were designed with exactly the same duration and lift on both the intake and exhaust lobes. But decades of engine research have determined that many engines (depending upon cylinder head airflow considerations) prefer more duration on the exhaust lobe than on the intake lobe. These are called dual-pattern cams, while the term single-pattern refers to cams with the same lift and duration on both the intake and exhaust.
    Now that we have the lift and duration numbers covered, let's move on to a few other more complex areas. Most cam lobe illustrations present the lobe as being symmetrical, which means if you folded the lobe down the middle and laid the opening and closing ramps on top of one another, they would be the same. But today, most cam designs are actually asymmetrical, meaning that the two ramps are not the same. This is especially true with intake lobes that are designed to slow the intake valve as it nears the seat to prevent it from slamming closed. This violent closing rate is usually what causes valve float.
    Each cam lobe also has a centerline. Many camshaft companies use the intake lobe centerline of cylinder No. 1 as a way to determine how the camshaft is phased with the engine. This intake centerline is expressed in terms of the number of crankshaft degrees after top dead center (ATDC). For example, a typical street cam will have an intake centerline between 106 and 112 degrees ATDC. Engine builders have found that advancing the centerline (i.e. 106 degrees ATDC) helps low-speed power while retarding the centerline (i.e. 112 degrees ATDC) hurts low-speed power and improves top-end power.
    Of course it's also correct that the exhaust lobe has a centerline that positions it in the four-stroke cycle. Therefore, there is a relationship between the position of the intake and exhaust lobes that is usually described as the lobe separation or lobe displacement angle. This is the angle (in cam degrees) between the intake and exhaust lobe centerlines. This separation angle is used to indicate the relative closeness of these two lobes.
    Looking at the valve timing graph that resembles two camel humps, you can easily see the distance (expressed in degrees) between the two lobe centerlines. This angle is established when the camshaft is machined and cannot be changed unless you grind a new cam. Looking at the middle of this graph, you can see that there is a short period of time, when the exhaust lobe is almost closed and the intake valve is just opening, that both valves are open. This is called valve overlap. That small triangle makes it easier to see the amount of overlap present in this particular camshaft.
    Generally, it is this amount of overlap combined with the amount of intake duration that can make a camshaft "lumpy," giving it that distinctive chop, or rough idle. If we lengthen the duration of the intake lobe by opening the intake sooner, the amount of valve overlap increases. Or, it's possible to increase overlap by merely shifting either the intake or exhaust lobe centerlines closer together. Conversely, we could also decrease overlap by moving either one or both centerlines apart. As you can begin to see, there are a ton of variables that can be tried when it comes to experimenting with cam timing.
    This has been a very basic introduction to cam timing and how all the different points of camshaft design interrelate to create this most complex engine component. Now that you know a little more about camshafts, you can take the next step and check out our camshaft selection story for big- and small-blocks. This story will help you get closer to choosing the proper camshaft for your next Bow Tie street-power project

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    More Ways to ShopLinksHome >> Cams & Valvetrain >> Camshaft >> Comp Cams 'Xtreme Energy' Mechanical Flat Tappet Camshafts


    Comp Cams 'Xtreme Energy' Mechanical Flat Tappet Camshafts




    Product images may differ from actual product appearance.

    The Leading Edge of Valve Train Technology Comp Cams' Xtreme Energy series can be used in any street or street/strip application where both throttle response and top-end horsepower is desired. These cams are designed to take advantage of the latest improvements in valve train components and the newest developments in camshaft design. Their aggressive lobe design produces better throttle response and top end horsepower than other cams with the same duration @ .050'' lift, while delivering increased engine vacuum. We do not recommend the use of stock valve train components with these camshafts due to the aggressive lobe designs.
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    حسن هادي
    حسن هادي غير متواجد حالياً
    عضو متميز
    الصورة الرمزية حسن هادي


    تاريخ التسجيل: Nov 2006
    المشاركات: 1,338
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