HOW TO SELECT A PERFORMANCE CAMSHAFT
When selecting a performance camshaft, consider the use for which the vehicle will be required.
We all know the claims: 20 BHP extra. This sounds great – but think! These automotive manufacturers can’t be that silly to disregard 20 BHP by changing a camshaft.
Ask yourself! Where is this 20 BHP? Probably not where you will ever use it at 7500 rpm. Well, probably we will use it, occasionally; it would be nice to have in reserve.
Hold on! In this world there is no such thing as a “free meal”. What’s the possible trade-off of this 20 BHP? It could be a loss of 10 BHP at 2500 rpm. This means, each time you accelerate through 2500 rpm, you could lose 10 BHP. This to me, doesn’t sound too
Be conservative! Don’t over-cam your engine. Choose your cam for the correct application. Consider! Fit a milder cam and increase
your power by 10 BHP at 3500 rpm.
Remember! You get this 10 HP every time you accelerate through 3500 rpm. Multiply this by 10 HP each time you drive through 3500 rpm then deduct the times you reach 7500 rpm.
I’m sure you will find more horsepower on the 3500 rpm side than the 7500 rpm calculation.
You will see that each camshaft has a Part No and Phase No. The Part Number designates the make and model/the duration period of the inlet camshaft/the valve lift of the inlet camshaft and whether the camshaft profile is hydraulic. So if we look at the Ford 1300/1600 CVH RS Turbo XR3i XR2 Camshaft Data Sheet we see the following:- FORC/206/420/H PH2
FORC Specifies the make and engine type
260 Specifies the duration
420 Specifies the lift on the inlet valve
H Specifies that the camshaft is designed for hydraulic cam followers
PH2 Specifies the type of use the camshaft is recommended for SELECTING YOUR CAMSHAFT
All the camshafts in this brochure have a Phase Number after the Part Number. Phases 1 to 5 will help you to select the camshaft that meets your requirements.
PHASE 1 (PH1) ROAD CAMSHAFT
This is a camshaft that would be used for road use and will normally run with standard carb or injection system and can be fitted without additional tuning equipment. It is meant for town use and will have a smooth tick-over and will give its increase in power in the low midrange.
Other modifications to the engine will increase the performance of this cam.
PHASE 2 (PH2) FAST ROAD CAMSHAFT
This is a camshaft for increasing mid-range of the engines and is meant for mild competition use and where the driver requires an
increase of power in the mid-range without suffering too much loss of power in the low-range. The tick-over will be heavier than a standard
engine. The fuel system may have to be modified and the cam will work to its optimum with modifications to the cylinder head, inlet/exhaust system and possibly the management system.
PHASE 3 (PH3) FAST ROAD RALLY
This type of camshaft is really the limit for normal road use. It will require fuel system and management modifications. It will have a noticeable loss of low-down power and the tick-over will be heavy. For competition use, where mid-range power is important and road
use where the maximum power is required.
PHASE 4 (PH4) TARMAC RALLY SPRINT RACE CAMSHAFT
This camshaft is for competition use only and can be considered as a _ race cam. It could be used on the road, but would not be suitable
for use in traffic. It will have a very heavy tick-over and there will be a noticeable loss of power below 3500 rpm. Its main use is for a torque race cam, giving a strong surge of power in the upper range power, yet still having the ability to floor the throttle below
5000 RPM and pull cleanly away. It will require modifications to the carb/injection system, cylinder head and induction exhaust system.
PHASE 5 (PH5) FULL RACE CAMSHAFT
For race use only. Not suitable for road or rally use,. Little power below 5000 RPM . Will have virtually no idle and will require carb/injection, exhaust/induction., cylinder head and engine management modifications.
MATERIAL TYPE (PERFORMANCE CAMSHAFTS)
You will note that we have a material description at the end of the camshaft specification. This informs of the following:
This means that the camshaft has been turned from a round steel bar and will normally be nitrided after grinding.
We use this method for low volume production and, due to the work involved, they are always more expensive than cast blanks
Unless specified, the camshaft is made from a chilled iron casting. This is the best material for camshafts, as it has far superior wear
characteristics than any other material.
A regrind on an existing camshaft, only suitable for mild grinds on existing chilled iron camshafts. If you regrind case hardened steel
camshafts you will remove the case hardening. We only regrind chilled iron cams, but prefer to supply new units
INFORMATION ON CAMSHAFT MATERIAL
Camshaft material, i.e., what the camshaft is made from, is the most important detail in stopping premature wear of performance
There are various materials that camshafts are manufactured from:-
2.SPHEROIDAL GRAPHITE CAST IRON KNOWN AS SG IRON
This is Grade 17 cast iron with an addition of 1% chrome to create 5 to 7% free carbide.
After casting, the material is flame/or induction hardened, to give a Rockwell hardness of 52 to 56 on the C Scale.
This material was developed in the 1930’s in America as a low-cost replacement for steel camshafts and is mainly suited in applications
where there is an excess of oil, i.e., camshafts that run in the engine block and that are splash-fed from the sump. (This is the material
that the Ford OHC camshafts were manufactured from).
It is not the most suitable material for performance camshafts in OHC engines.
As a company, we only use this material for performance camshafts if the camshaft is splash-fed in the sump.
A material giving similar characteristics to hardenable. Its failing as a camshaft material is hardness in its cast form, i.e., Rockwell 5,
which tends to scuff bearings in adverse conditions. The material will heat treat to 52 to 58 Rockwell C. This material was used by Fiat
in the 1980’s.
3.CHILLED CHROME CAST IRON
Chilled iron is Grade 17 cast iron with 1% chrome. When the camshaft is cast in the foundry, machined steel moulds the shape of the
cam lobe are incorporated in the mould. When the iron is poured, it hardens off very quickly (known as chilling), causing the cam lobe
material to form a matrix of carbide (this material will cut glass) on the cam lobe.
This material is exceedingly scuff-resistant and is the only material for producing quantity OHC performance camshafts.
CONCLUSION OF CAST CAMSHAFTS
When purchasing a camshaft, enquire which material the camshafts are produced from. A chilled iron camshaft may be more expensive,
but its resistance to wear in all conditions, far exceeds any other type of cast iron.
1.CARBON STEEL – EN8/EN9
Used mainly in the 1930 to 1945 period and is currently used for induction hardened camshafts in conjunction with roller cam followers,
due to the through-hardening characteristics of the material.
2.ALLOYED STEELS – EN351 AISI 8620 and EN34 etc
Used by British Leyland in the A Series and B Series engine and best when run against a chilled cam follower.
3.NITRIDING STEEL – EN40B
The best steel for camshafts. When nitrided it gives a surface hardness and finish similar to chilled iron.
We used this when replacing chilled iron camshafts in competition engines. This material is used on several of the current F1 engines.
In general, steel is a good camshaft material. However, the type of steel has to be matched with the cam follower it runs against, as different grades of steel have different scuff characteristics. Be careful when buying camshafts without specifications or material information.
GENERAL CONCLUSION OF CAMSHAFT MATERIAL
This has been a very simplified explanation of camshaft materials, based on over 38 year’s experience. It may assist you to ask the
correct questions when purchasing performance camshafts.
Whether you buy cams from us or someone else we hope that you get the best cam for your needs. We aim at supplying many cam options from the highest quality,the most reputable manufacturers-
-Newman Cams and Colombo and Bariani offered by Alfissimo International.
Alfa 164 Technical Service Bulletin 21.94.01
Information: Alignment Specifications for 164
Models: 1991 thru 1995 164 All
The alignment specifications for all model year 164's have been revised and simplified.
1991-1995 164 ALL
Front Camber -1.1 a to -2.4
Front Caster - + 1.0 to + 2.6
Front Total Toe - 0mm to -2mm
Rear Camber - +0.1 o to -1.8
Rear Total Toe - +4mm to +6mm
NOTE: When running a larger wheel/tire combo 16"+
Front Total Toe - 0mm to -2mm
Rear Total Toe - 0mm to -2mm
Please, update all of the 1991 & 1994 164 Service Manuals in your dealership by makeing the corrections within Group 21 on pages 21-12, 21-13, 21-15, 21-27, 21-28, 21-29. Please refer to the attached sample page.
The locations for the changes are called out by this little pencil--->
ALSO: The statements "Values refer to static load vehicle" and "For vehicles enuipped with spacers between engine support frame and bodywork" will no longer be used. In the 1991 164 Service Manual the "PITCH ANGLE" is CASTER ANGLE
This T.S.B. supersedes all previous publications including specifications found in service manuals.
Exhaust Information, "is larger better"?
1. Begin at the corner furthest from the driver and proceed in order toward the driver. (Right rear, left rear, right front, left front.) While the actual sequence is not critical to the bleed performance it is easy to remember the sequence as the farthest to the closest. This will also allow the system to be bled in such a way as to minimize the amount of potential cross-contamination between the new and old fluid.
2. Locate the bleeder screw at the rear of the caliper body (or drum brake wheel cylinder.) Remove the rubber cap from the bleeder screw – and don't lose it!
3. Place the box-end wrench over the bleeder screw. An offset wrench works best – since it allows the most room for movement.
4. Place one end of the clear plastic hose over the nipple of the bleeder screw.
5. Place the other end of the hose into the disposable bottle.
6. Place the bottle for waste fluid on top of the caliper body or drum assembly. Hold the bottle with one hand and grasp the wrench with the other hand.
7. Instruct the assistant to "apply." The assistant should pump the brake pedal three times, hold the pedal down firmly, and respond with "applied." Instruct the assistant not to release the brakes until told to do so.
8. Loosen the bleeder screw with a brief ¼ turn to release fluid into the waste line. The screw only needs to be open for one second or less. (The brake pedal will "fall" to the floor as the bleeder screw is opened. Instruct the assistant in advance not to release the brakes until instructed to do so.)
9. Close the bleeder screw by tightening it gently. Note that one does not need to pull on the wrench with ridiculous force. Usually just a quick tug will do.
10. Instruct the assistant to "release" the brakes. Note: do NOT release the brake pedal while the bleeder screw is open, as this will suck air back into the system!
11. The assistant should respond with "released."
12. Inspect the fluid within the waste line for air bubbles.
13. Continue the bleeding process (steps 11 through 16) until air bubbles are no longer present. Be sure to check the brake fluid level in the reservoir after bleeding each wheel! Add fluid as necessary to keep the level at the MAX marking. (Typically, one repeats this process 5-10 times per wheel when doing a ‘standard' bleed.)
14. Move systematically toward the driver – right rear, left rear, right front, left front - repeating the bleeding process at each corner. Be sure to keep a watchful eye on the brake fluid reservior! Keep it full!
15. When all four corners have been bled, spray the bleeder screw (and any other parts that were moistened with spilled or dripped brake fluid) with brake cleaner and wipe dry with a clean rag. (Leaving the area clean and dry will make it easier to spot leaks through visual inspection later!) Try to avoid spraying the brake cleaner DIRECTLY on any parts made of rubber or plastic, as the cleaner can make these parts brittle after repeated exposure.
16. Test the brake pedal for a firm feel. (Bleeding the brakes will not necessarily cure a "soft" or "mushy" pedal – since pad taper and compliance elsewhere within the system can contribute to a soft pedal. But the pedal should not be any worse than it was prior to the bleeding procedure!)
17. Be sure to inspect the bleeder screws and other fittings for signs of leakage. Correct as necessary.
18. Properly dispose of the used waste fluid as you would dispose of used motor oil. Important: used brake fluid should NEVER be poured back into the master cylinder reservoir!
Vehicle Wrap-Up and Road Test
1. Re-install all four road wheels.
2. Raise the entire vehicle and remove jackstands. Torque the lug nuts to the manufacturer's recommended limit. Re-install any hubcaps or wheel covers.
3. With the vehicle on level ground and with the car NOT running, apply and release the brake pedal several times until all clearances are taken up in the system. During this time, the brake pedal feel may improve slightly, but the brake pedal should be at least as firm as it was prior to the bleeding process.
4. Road test the vehicle to confirm proper function of the brakes. USE CAUTION THE FIRST TIME YOU DRIVE YOUR CAR AFTER MODIFICATION TO ENSURE THE PROPER FUNCTION OF ALL VEHICLE SYSTEMS!
Bedding in NEW pads or Rotors
Often times, weather or other conditions can prevent one from fully bedding-in the brakes before having to drive the car. Fortunately, this is not a dire situation. If you are running new street/performance pads and rotors, remember that they are designed for the street and will slowly bed-in by themselves over time. Typically just a few stops from moderate speeds will start the bed-in process for normal driving.
In general, as long as the brakes are not overheated, you can drive them at normal street limits indefinitely without worrying about a formal bed-in. It's only when you get them good and hot that a fully bedded-in system becomes so important. This is why we recommend a slightly more aggressive bed-in procedure than most…we know performance brake customers are not “normal” and typically can't wait to try their new brakes at speed.
For a typical OEM Alfa Braking system using street-performance pads, a series of ten partial braking events, from 60mph down to 10mph, will typically raise the temperature of the brake components sufficiently to be considered one bed-in set. Each of the ten partial braking events should achieve moderate-to-high deceleration (about 80 to 90% of the deceleration required to lock up the brakes and/or to engage the ABS), and they should be made one after the other, without allowing the brakes to cool in between.
Depending on the make-up of the pad material, the brake friction will seem to gain slightly in performance, and will then lose or fade somewhat by around the fifth stop (also about the time that a friction smell will be detectable in the passenger compartment). This does not indicate that the brakes are bedded-in. This phenomenon is known as a green fade, as it is characteristic of immature or ‘green' pads, in which the resins still need to be driven out of the pad material, at the point where the pads meet the rotors. In this circumstance, the upper temperature limit of the friction material will not yet have been reached.
As when bedding-in any set of brakes, care should be taken regarding the longer stopping distance necessary with incompletely bedded pads. This first set of stops in the bed-in process is only complete when all ten stops have been performed - not before. The system should then be allowed to cool, by driving the vehicle at the highest safe speed for the circumstances, without bringing it to a complete stop with the brakes still applied. After cooling the vehicle, a second set of ten partial braking events should be performed, followed by another cooling exercise. In some situations, a third set is beneficial, but two are normally sufficient.
Suspension: lowering, koni's and more
Understanding Cooling Systems
Cooling System upgrades for the Alfa Romeo
It’s helpful to understand that, during operation, internal combustion engines convert the energy of fuel into mechanical work and heat. Approximately one-third of the fuel energy goes into the mechanical work of the moving vehicle, one-third into exhaust heat, and one-third into heat transferred by the engine cooling system to the ambient air.
This means that heat load to the cooling system at rated power (Usually expressed in BTUs per minute) is approximately equal to the rated power of the engine expressed in BTUs per minute (HP X 42.4 = BTU/minute). From this we can see that if an engine is modified to increase its horsepower, the load to the cooling system will also increase. In fact, the heat load to the cooling system will increase by about the same percentage as the increase in engine horsepower. So, if we increase the engine horsepower by 20 percent, we can expect an increase of about 20 percent in the heat load to the cooling system.
Cooling system heat transfer is governed by a single major factor-the heat load to the cooling system. Under “steady-state” conditions, the heat load to the cooling system (the heat rejected by the engine to the cooling system) will be transferred to the cooling air by the radiator no matter how good or how poor the radiator. So, if both a “poor” radiator and a “good” radiator will both transfer the same heat load to the cooling air, how can we say that one radiator has better heat transfer performance than the other? The answer is that, under “steady-state” conditions, with a “good” radiator in the cooling system, the radiator inlet temperature (Radiator top tank temperature) will stabilize at a lower temperature than a “poor radiator” in place. The “poor radiator may be so poor that its coolant temperature may rise to the boiling point resulting in engine overheating.
The difference between the radiator average core temperature and the temperature of the cooling air is the driving force behind the transfer of heat from the coolant to the cooling air. When an engine starts and is run up to rated load, the coolant begins to heat up. When there is no thermostat in the system, the coolant flows from the engine through the radiator and back to the engine. Initially, the coolant and metal in the engine absorb the heat being produced and continue to do so until the temperature of these parts exceeds the cooling air temperature. At this point, heat transfer to the cooling air commences. The coolant temperature continues to rise until it reaches a temperature at which the difference between the radiator average core temperature and the incoming cooling air is great enough to transfer the entire heat load to the air. This then becomes a “steady-state” condition.
A cooling system whose heat load and coolant flow rate results in a 10 degree F coolant temperature drop through the radiator will have that same coolant temperature drop whether the radiator has a very small face area and flat fins or a very large face area and louvered fins. The difference is that the large louvered fin radiator will be more effective than the small radiator at transferring heat to the cooling air, meaning that it can do it with a much lower difference in temperature between the core and cooling air. The small radiator may require such a high difference in temperature between the core and the cooling air and the core that the coolant may reach boiling temperature before the core is able to transfer all of the heat load to the cooling air. While both radiators would have the same coolant temperature drop through the radiator, we would say that the larger radiator had better heat transfer performance if its top tank temperature (Inlet coolant temperature) stabilized at, say, 180 degrees F while the smaller radiator stabilized at 220 degrees F.
Improving an Overheated Cooling System
With this understanding of how a cooling system works what recommendations should we make for a cooling system that is overheating? Suppose we have an engine and cooling system that, in stock condition, produced a rated 200 hp and ran at rated ambient temperature with a top tank temperature of 190 degrees F and a 10 degree F temperature drop through the radiator. Now suppose the engine were modified to produce 240 hp, a 20 percent increase. We would find that at 240 hp the core temperature drop had increased by 20 percent to 12 degrees F and the top tank temperature had increased, let’s say to the point where it was just overheating. Now suppose we take this system and reduce the power to the point where the radiator inlet, or top tank temperature is steady at 190 degrees F. (Guess what? It’ll be producing 200 hp! Funny, how that works). So we check coolant temperature drop and find it is back to 10 degrees F, as we would expect, meaning the average core temperature is 185 degrees F. Now we want to make improvements to the system in order to lower the top tank temperature to the point where we can then go back to 240 hp without the engine overheating.
Now for some improvements for your alfa cooling system:
Cooling air becomes heated as it passes through the radiator. It enters the radiator at ambient temperature and exits the radiator at some increased temperature. It is the difference between the average core, or coolant temperature and the average of these two cooling air temperatures that creates the ability of the radiator to transfer heat to the air. The slower the air passes through the radiator, the higher will be its exit temperature and the higher will be the average cooling air temperature. The higher the average cooling air temperature, the less heat will be transferred from the coolant to the air. On the contrary, the faster the air flows through the core, the less it will increase in temperature on its way through, making the exit temperature and the average cooling air temperature lower. This increases the differential between the average core temperature and the average air temperature, increasing the heat transfer. Increasing airflow by speeding up the fan, by providing an improved fan, by providing or improving the fan shroud, by reducing air restrictions in the grille or engine compartment, or by providing recirculation shields to prevent air from bypassing the core, will all improve heat transfer and cooling.
Radiator Face Area
As we have seen, cooling air becomes warmer as it passes through the radiator. Coolant in the back row of a radiator is cooled by warmer cooling air that coolant in the front row of a radiator. Increasing the face area of a radiator exposes more coolant to the coolest ambient cooling air, increasing the radiator heat transfer capability.
Increasing the radiator face area may not be practical in all cased because of space limitations. However, similar improvement may be obtained by relocating any air conditioning condenser, or oil cooler which may be in front of the radiator, thereby exposing more of the face area of the radiator to the coolest ambient cooling air.
Increasing the radiator fin count, or number of fins per inch, provides more surface area for the transfer of heat to the cooling air. However, increasing the fin count increases the restriction of the radiator to cooling airflow. Lower cooling airflows result in lower heat transfer. In every installation there is an optimum combination of fin performance and core restriction that will produce maximum heat transfer. Increasing the core restriction from this optimum point by increasing fin count will reduce the heat transfer performance of the radiator. On the other hand, if the original radiator has a very low fin count, increasing will improve heat transfer. In general, for high performance applications, fin counts from 12 fins per inch to 18 fins per inch are optimum. Increasing the fin count above 18 fins per inch will almost always result in reduced heat transfer performance. Since, as we have seen, in a given installation under “steady-state” conditions the radiator must transfer the given heat load no matter what, the reduced heat transfer performance resulting from an excessively restrictive high fin count must be compensated for by increased coolant temperature, possibly to the point of overheating.
Radiator fins, whether plated or serpentine types, may be louvered or non-louvered. Louvered fins turbulate the air passing through the radiator to increase the “scrubbing action” of the cooling air, providing greatly improved heat transfer with some increase in air restriction. Louvered fins also tend to become clogged with dust and debris more readily than non-louvered fins, but for high performance applications are the only way to go. Non-louvered fins are typically used on farm and construction equipment, operating in dirty environments. Non-louvered fins may be made with patterns of dimples, waves, or bumps in order to provide turbulance without clogging.
Water has a higher specific heat than an ethylene glycol or propylene glycol coolant mix. Therefore, it provides the best heat transfer performance in a cooling system. If a cooling system is marginal, that is, it only overheats on the hottest of days, then running with water as a coolant in the summer and an ethylene glycol or propylene glycol coolant solution during the rest of the year will probably solve the problem. Commercial coolant solutions provide cooling, anti-freeze protection, corrosion inhibitors to protect the metals in the cooling system, and a lubricant for the water pump. When running water as a coolant for maximum heat transfer, a product that provides a corrosion inhibitor and water pump lubricant should be added to the water.
In terms of the relative heat transfer performance of ethylene glycol versus propylene glycol coolant bases, they are pretty much equal when mixes according to the manufacturers’ recommendations, usually a 50/50 water to glycol mix. Ethylene glycol coolant solutions provide slightly higher heat transfer performance over propylene glycol solutions at low coolant flow rates.
What is TUV?
T.Ü.V. (Technischer Überwachungs Verein) is a German Government agency that regulates automotive products to maintain motor vehicle safety standards. In Germany, no automotive modifications are allowed unless that part has been approved for use by T.Ü.V.
T.Ü.V. approvals require precise descriptions of the materials, production methods and quality assurance details. Loose sample springs must be readily available for laboratory testing, load compression curves, and spring rate force at any time.
The T.Ü.V. also fits springs into vehicles for extensive test-drives. The test car is tested in fully loaded and empty modes, and at normal and race speeds. It is only upon successful completion of these tests that a T.Ü.V. Approval Certificate is issued.