1. Off the Shelf Performance Parts Many, many aftermarket parts to choose from Many, many aftermarket parts to choose from Many are poorly designed and tested Many are poorly designed and tested Make an educated decision Make an educated decision If it’s cheap, it’s probably because it’s cheap If it’s cheap, it’s probably because it’s cheap Avoid products that use ‘buzzwords’ or slang in place of technical terms. Avoid products that use ‘buzzwords’ or slang in place of technical terms. It is a ‘you get what you pay for’ world, but it can also sometimes be a ‘you paid too much for what you got’ world. It is a ‘you get what you pay for’ world, but it can also sometimes be a ‘you paid too much for what you got’ world. Remember to build your torque curve for your application and choose parts that develop torque in the right area of the rev band. Remember to build your torque curve for your application and choose parts that develop torque in the right area of the rev band.

2. Off the Shelf Performance Parts Intakes Intakes Stock air box is there to muffle noise. Stock air box is there to muffle noise. Inside airbox is a labyrinth used to cancel out noise Inside airbox is a labyrinth used to cancel out noise Stock intake is ‘the other muffler’ Stock intake is ‘the other muffler’ Air does not like to turn corners, this makes the airbox restrictive especially at higher rpm. Air does not like to turn corners, this makes the airbox restrictive especially at higher rpm. Cold air intakes Cold air intakes Cold air intakes Cold air intakes Air intake tube pulls air from outside the engine compartment Air intake tube pulls air from outside the engine compartment Outside air is colder, and therefore more dense. Outside air is colder, and therefore more dense. Is usually a straight shot to the throttle body or carburetor, no labrinth. Is usually a straight shot to the throttle body or carburetor, no labrinth. Flow better, provides additional horsepower at higher rpm. Flow better, provides additional horsepower at higher rpm. At lower rpm, volume of airflow is less so power increase is less. At lower rpm, volume of airflow is less so power increase is less. Cold air intakes can make engine sound much better. Cold air intakes can make engine sound much better.

3. Off the Shelf Performance Parts Intakes Intakes Short Ram intakes (or just an air filter on carburetors) Short Ram intakes (or just an air filter on carburetors) Short Ram intakes or just an air filter on carburetors Short Ram intakes or just an air filter on carburetors Basically just a performance filter shoved onto the throttle body. Basically just a performance filter shoved onto the throttle body. Sucks in all its air from under the hood. Sucks in all its air from under the hood. Air under the hood is hot, not conducive to good power. Air under the hood is hot, not conducive to good power. Airflow into engine compartment when vehicle is moving is not enough to offset heat of engine. Airflow into engine compartment when vehicle is moving is not enough to offset heat of engine. On FI engines, as vehicle sits at stoplight ECU picks up heat from IAT sensor. On FI engines, as vehicle sits at stoplight ECU picks up heat from IAT sensor. Mixture gets richer Mixture gets richer Timing is retarded Timing is retarded When vehicle starts moving again, it takes a while for mixture and timing to improve When vehicle starts moving again, it takes a while for mixture and timing to improve Falsely show power on the dyno, because hood is open. Falsely show power on the dyno, because hood is open.

4. Off the Shelf Performance Parts Performance air filters Performance air filters Efficiency: How efficiently the filter can trap small particles Efficiency: How efficiently the filter can trap small particles Capacity: How much dirt the filter can hold before it becomes restrictive Capacity: How much dirt the filter can hold before it becomes restrictive These definitions apply to all filters. These definitions apply to all filters. A standard paper filter element is most efficient at filtering dirt A standard paper filter element is most efficient at filtering dirtpaper filter element paper filter element Flows well when new Flows well when new Gets restrictive faster Gets restrictive faster Surface area is key to capacity Surface area is key to capacity The best choice for the street The best choice for the street ‘K and N’ type filters flow very well ‘K and N’ type filters flow very well ‘K and N’ type filters ‘K and N’ type filters Not as efficient at removing dirt, K&N does not claim it does, advertiser do. Not as efficient at removing dirt, K&N does not claim it does, advertiser do. Flow well when new Flow well when new Flow well when partially dirty Flow well when partially dirty This is the key advantage of this type This is the key advantage of this type Have high capacity. Have high capacity. All filters are most efficient when dirty All filters are most efficient when dirty A clean air filter will not ‘protect your engine better’ A clean air filter will not ‘protect your engine better’ As particles get trapped on top of each other they create smaller and smaller pores As particles get trapped on top of each other they create smaller and smaller pores A dirty air filter will not reduce mileage on a modern fuel injected vehicle A dirty air filter will not reduce mileage on a modern fuel injected vehicle A dirty air filter can cause mixture to be rich on a carbureted engine A dirty air filter can cause mixture to be rich on a carbureted engine

5. Off the Shelf Performance Parts Mass air flow meters (draw on board) Mass air flow meters (draw on board) Mass air flow meters Mass air flow meters MAF’s are tuned for emissions from the factory MAF’s are tuned for emissions from the factory Real gains can be made at high RPM Real gains can be made at high RPM Bore is small to keep velocity high at low rpm Bore is small to keep velocity high at low rpm This makes readings accurate at low rpm This makes readings accurate at low rpm MAF ‘element’ (the actual measuring part) are usually replaceable MAF ‘element’ (the actual measuring part) are usually replaceableelement Allows you to replace with a larger housing without replacing element Allows you to replace with a larger housing without replacing elementreplace with a larger housing replace with a larger housing Mass air flow meters are tapered Mass air flow meters are tapered Increase velocity of air past the sensor Increase velocity of air past the sensor Straight sensors can cause erratic readings Straight sensors can cause erratic readings Straight housing causes surging or stalling at idle Straight housing causes surging or stalling at idle

6. Off the Shelf Performance Parts Mass air flow meters Mass air flow meters Takes reading ‘sample’ from center of bore Takes reading ‘sample’ from center of bore Relocating sensor into a curve is a bad idea Relocating sensor into a curve is a bad idea You may do this if installing a turbo kit, for example You may do this if installing a turbo kit, for example Air will get thrown to the outside of the pipe and not get measured Air will get thrown to the outside of the pipe and not get measured This causes inaccurate readings as the center of airflow changes at different loads and rpms. This causes inaccurate readings as the center of airflow changes at different loads and rpms. Larger MAF requires recalibration Larger MAF requires recalibration For same amount of voltage, MAF output voltage will be lower For same amount of voltage, MAF output voltage will be lower Computer can not compensate Computer can not compensate Computer must be retuned to work with MAF Computer must be retuned to work with MAF (Draw voltage curve on board) (Draw voltage curve on board)

7. Off the Shelf Performance Parts Throttle bodies Throttle bodies Bore of throttle body can be made larger Bore of throttle body can be made larger Increases total flow Increases total flow Power gains will show up at higher RPM Power gains will show up at higher RPM If increasing redline of engine will be needed If increasing redline of engine will be needed May show improvements on stock engine because stock throttle body is tuned for idle/low speed May show improvements on stock engine because stock throttle body is tuned for idle/low speed Will need to make new throttle plates Will need to make new throttle plates Plate is not round, requires some math to determine proper size. Plate is not round, requires some math to determine proper size. Electronic ‘fly-by-wire’ throttles may need to be remapped for drivability (draw on board) Electronic ‘fly-by-wire’ throttles may need to be remapped for drivability (draw on board) Can make power more ‘linear’ (draw map on board) Can make power more ‘linear’ (draw map on board)

8. Off the Shelf Performance Parts Intake manifolds (draw on board, label parts) Intake manifolds (draw on board, label parts) Larger (more volume in the runner, plenum) manifolds make more power Larger (more volume in the runner, plenum) manifolds make more power Short, fat runners for optimum high rpm Short, fat runners for optimum high rpm Long, narrow runner for optimum low rpm Long, narrow runner for optimum low rpm Raise torque peak higher in the rpm band Raise torque peak higher in the rpm band Velocity drops at lower rpm with large runners, this can be detrimental to low end torque Velocity drops at lower rpm with large runners, this can be detrimental to low end torque Aluminum manifolds can be ‘Extrude Honed’ Aluminum manifolds can be ‘Extrude Honed’Extrude HonedExtrude Honed Abrasive paste is forced through manifold to remove material and polish walls of manifold Abrasive paste is forced through manifold to remove material and polish walls of manifold Follows existing contour. Follows existing contour. Fuel injection manifolds only have to flow air Fuel injection manifolds only have to flow air Fuel and air does not stay homogenous (well mixed) when it has to turn corners Fuel and air does not stay homogenous (well mixed) when it has to turn corners This is one of the main advantages of fuel injection This is one of the main advantages of fuel injection

9. Off the Shelf Performance Parts Intake manifolds Intake manifolds Carbureted manifolds for V8’s Carbureted manifolds for V8’s Dual plane manifolds Dual plane manifolds Create peak torque in the lower RPM range Create peak torque in the lower RPM range Best for street vehicles and trucks Best for street vehicles and trucks One side of carb feeds 4 cylinders, other side feeds other 4 One side of carb feeds 4 cylinders, other side feeds other 4 Creates smaller runners and plenum, more velocity Creates smaller runners and plenum, more velocity Image: Dual plane manifold Image: Dual plane manifoldDual plane manifoldDual plane manifold Single plane manifolds Single plane manifolds Create torque in higher RPM range Create torque in higher RPM range Best for racing vehicles and lightweight vehicles Best for racing vehicles and lightweight vehicles All 4 barrels of carburetor feeds all cylinders All 4 barrels of carburetor feeds all cylinders Larger plenum and larger effective runners Larger plenum and larger effective runners Image: Single plane manifold Image: Single plane manifoldSingle plane manifoldSingle plane manifold

10. Off the Shelf Performance Parts Intake manifolds Intake manifolds Tunnel Ram Tunnel Ram Not for street use Not for street use Uses large diameter, long runners to build velocity at high RPM. Uses large diameter, long runners to build velocity at high RPM. Have poor drivability and torque at low RPM Have poor drivability and torque at low RPM Usually have two carburetors Usually have two carburetors Good for raising impression ratio, your friends will be impressed Good for raising impression ratio, your friends will be impressed Image: Tunnel ram intake Image: Tunnel ram intakeTunnel ram intakeTunnel ram intake

11. Off the Shelf Performance Parts Intake manifolds Intake manifolds Other available parts Other available parts Intake trumpets Intake trumpets Intake trumpets Intake trumpets Velocity stacks Velocity stacks Velocity stacks Velocity stacks

12. Off the Shelf Performance Parts Cylinder heads Cylinder heads Cylinder heads Cylinder heads Variety of aftermarket heads available for both domestic and import engines Variety of aftermarket heads available for both domestic and import engines Can get aluminum heads for engine originally equipped with iron heads, can use higher effective compression ratio = more power. Can get aluminum heads for engine originally equipped with iron heads, can use higher effective compression ratio = more power. Good heads are CNC ported. Hand ported heads can be inconsistent from cylinder to cylinder. Some heads are ‘as cast’ and can be hand polished = lower cost. Good heads are CNC ported. Hand ported heads can be inconsistent from cylinder to cylinder. Some heads are ‘as cast’ and can be hand polished = lower cost. Good heads are CNC ported Good heads are CNC ported Choose your heads before choosing cam Choose your heads before choosing cam Have upgraded valves, retainers, keepers, springs, etc. Have upgraded valves, retainers, keepers, springs, etc. Using displacement ratio math, determine what volume (cubic centimeters or inches) combustion chamber you need to achieve your desired compression ratio. Using displacement ratio math, determine what volume (cubic centimeters or inches) combustion chamber you need to achieve your desired compression ratio. Get manufacturer supplied flow chart from flow bench to help determine which cam you need. Get manufacturer supplied flow chart from flow bench to help determine which cam you need. Manufacturer should be able to help you determine what port volume you need to achieve your power goals. Manufacturer should be able to help you determine what port volume you need to achieve your power goals. In general, smaller ports will develop torque in the lower rpm range and larger ports will develop torque higher in the rpm band. In general, smaller ports will develop torque in the lower rpm range and larger ports will develop torque higher in the rpm band. Have upgraded valves, retainers, keepers, springs, etc. Have upgraded valves, retainers, keepers, springs, etc.

13. Off the Shelf Performance Parts Camshafts Camshafts There are way too many aftermarket camshafts on the market. There are way too many aftermarket camshafts on the market. Terms such as ‘stage 1’, ‘stage 2’, ‘tuner series’, ‘pro series’, ‘fast ramp’, ‘Xtreme’, ‘fireball’, ‘thumpr’, etc are all marketing buzzwords and are COMPLETELY USELESS. Terms such as ‘stage 1’, ‘stage 2’, ‘tuner series’, ‘pro series’, ‘fast ramp’, ‘Xtreme’, ‘fireball’, ‘thumpr’, etc are all marketing buzzwords and are COMPLETELY USELESS. Many companies sell camshafts that were manufactured by someone else, and put it a box with the companies name on it. Many companies sell camshafts that were manufactured by someone else, and put it a box with the companies name on it. A cylinder head flow chart is needed to properly choose the lift of a camshaft. A cylinder head flow chart is needed to properly choose the lift of a camshaft. In general, the higher the engine revs, the more duration the camshaft will need to have. In general, the higher the engine revs, the more duration the camshaft will need to have. Camshaft selection is extremely complicated. Camshaft selection is extremely complicated. It is best to let the experts give you advice, no one persons knows everything there is to know about engines. It is best to let the experts give you advice, no one persons knows everything there is to know about engines. Don’t be afraid to get advice from more than one source. Don’t be afraid to get advice from more than one source. Camshafts have a bigger influence on power than anything else. Camshafts have a bigger influence on power than anything else. Once a cam is broken in, it must not be separated from its paired lifters. Once a cam is broken in, it must not be separated from its paired lifters. Always use new lifters on American V8’s Always use new lifters on American V8’s

14. Off the Shelf Performance Parts Exhaust manifolds/headers Exhaust manifolds/headers Stock exhaust manifolds are made for emissions/cost Stock exhaust manifolds are made for emissions/cost Designed to keep heat in so they heat up the catalytic converter as fast as possible. Designed to keep heat in so they heat up the catalytic converter as fast as possible. Often are very restrictive and a good way to ‘free up’ power. Often are very restrictive and a good way to ‘free up’ power. Newer vehicles have ‘pre-cats’ close to exhaust ports to ‘light off’ quicker. Newer vehicles have ‘pre-cats’ close to exhaust ports to ‘light off’ quicker. ‘Headers’ are made of steel tubing and flow better than cast iron manifolds. ‘Headers’ are made of steel tubing and flow better than cast iron manifolds. Length and diameter of primary pipes, as well as header configuration determine rpm range. Length and diameter of primary pipes, as well as header configuration determine rpm range. Tri-Y header – best for producing torque at a lower rpm Tri-Y header – best for producing torque at a lower rpm Tri-Y header Tri-Y header 4 into 1 header – best for producing torque at higher rpm 4 into 1 header – best for producing torque at higher rpm 4 into 1 header 4 into 1 header Has to do with timing of exhaust pulses. ‘Rarefraction’ timed to help draw in air and fuel during valve overlap. Has to do with timing of exhaust pulses. ‘Rarefraction’ timed to help draw in air and fuel during valve overlap. Balance pipe – Used on V8 engines that do not have a flat plane crank. Balance pipe – Used on V8 engines that do not have a flat plane crank. Dinan headers Dinan headers Dinan headers Dinan headers Get A. Graham Bell’s book Performance Tuning in Theory and Practice for good information on exhaust system design. Get A. Graham Bell’s book Performance Tuning in Theory and Practice for good information on exhaust system design.

15. Off the Shelf Performance Parts Mufflers Mufflers High performance mufflers have less restriction. High performance mufflers have less restriction. Will make more power higher in the rpm band. Will make more power higher in the rpm band. Low rpm will see little gains unless there was a problem with the original design. Low rpm will see little gains unless there was a problem with the original design. ‘Tunes’ the sound of the engine – like a musical instrument. ‘Tunes’ the sound of the engine – like a musical instrument. Universal performance mufflers may or may not work well on your car. Universal performance mufflers may or may not work well on your car. Application specific mufflers are designed by trial and error – tuned to what is most pleasing to the ear. Application specific mufflers are designed by trial and error – tuned to what is most pleasing to the ear. Helmholtz principal used on good mufflers (draw on board). Helmholtz principal used on good mufflers (draw on board).

16. Off the Shelf Performance Parts Electronics Electronics Power chips Power chips Make power by altering fuel and spark Make power by altering fuel and spark Optimize for premium fuel Optimize for premium fuel ‘Software’ ‘Software’ Can be programmed through OBDII port Can be programmed through OBDII port Alters fuel, spark, cam phasing, fly-by-wire throttle, idle, rev limit, top speed, etc. Alters fuel, spark, cam phasing, fly-by-wire throttle, idle, rev limit, top speed, etc. Plug and Play ECU’s Plug and Play ECU’s Plug into existing wiring and allow tuneability Plug into existing wiring and allow tuneability Stand alone ECU’s Stand alone ECU’s Eliminate any emissions controls but allow ultimate in flexibility. Eliminate any emissions controls but allow ultimate in flexibility.