Page 60

Ford Racing Catalogue Web

ENGINE TECH TIPS ENGINE INSTALLATION AND TUNING TIPS Performance engine durability is dependent on several • Avoid inductive crossfire created by improper plug COOLING SYSTEM CONSIDERATIONS/ supporting systems including the cooling system, fuel wire routing. Separate plug wires on cylinders that COMMON PROBLEMS delivery system, ignition system and oiling system. fire in sequence. • Higher horsepower requires more cooling capacity. If the support systems are not adequate, poor engine • Improper timing can damage pistons, rod bearings, • When the fill point of the cooling system is not performance and possible engine failure could result. head gaskets and many other engine parts. the highest point, air pockets are created. The • Typical total mechanical advance timing at air pockets then create hot spots, and the hot spots OILING SYSTEM CONSIDERATIONS/ 4000 rpm for Ford Racing Performance Parts promote improper combustion, which can cause COMMON PROBLEMS crate engines: 5.0L: 36° to 38°, 347/351: 34° to 36°, engine failure. • Priming the oiling system before starting a new • Improper pulley size makes the fan and water pump392/460/514: 30° to 32°. engine is crucial to engine life. This is important on turn too slow or too fast. Production water pumps initial start-up of a new engine and if a used engine FUEL DELIVERY CONSIDERATIONS are normally run at 20% over engine speed and do has not been run for extended periods of time. • Size of fuel pump, size of fuel line, fuel pump not perform well over 5000 engine rpm. Underdrive • Does the oil pan have adequate capacity? Most placement, fuel filter placement, fuel filter size, pulleys generally reduce water pump speed to 85% performance vehicles require a 7 qt. minimum injector size, fuel rail size, fuel pressure, jet size of engine rpm and may not provide enough water capacity. All engines will benefit from increased and baffling in the fuel tank. flow to cool the engine. oil pan capacity. • Does the fuel system maintain full pressure • The radiator must have enough area to dissipate • Does the oil pan have proper oil control baffling for at peak engine horsepower in high gear? the heat being generated by the engine. the vehicle’s braking, acceleration and cornering • If the fan size is too small, it will not move enough capabilities? Road-race cars need oil control in Altitude, air temperature and fuel characteristics air across the radiator so it can properly dissipate four directions: braking, acceleration, LH cornering including quality, specifi c gravity and octane rating will the heat being generated. Fan shrouds increase and RH cornering. Drag race cars need oil control aff ect your jetting requirements. Engine effi ciency and the effectiveness of the fan significantly. in two directions: braking and acceleration. Brake Specifi c Fuel Consumption (BSFC) also have an • Radiator location can affect airflow through the Baffles must be designed to keep oil over the eff ect. Here are some examples of a Holley® 750 CFM 4V. radiator at different vehicle speeds. pickup screen at all times. • Is the pickup screen the proper distance from the Jetting Jetting FLYWHEEL, CONVERTER AND bottom of the oil pan? If the oil pickup screen is Octane Temp. Altitude Front Rear TRANSMISSION PROBLEMS too close to the bottom of the oil pan, it can cause 94 80 F 0 ft . 81 86 • Installing the wrong flywheel for the balance factor cavitation. If it is too far away, it will cause the pump of the engine will cause vibration and eventually84810 ft .80 FAviation 100LL to draw air and minimize lubrication capacity. The damage the engine. pickup screen should be located .250" to .375" from 110 Race 80 F 0 ft . 78 83 • Wrong length input shaft or “stack-up height” the bottom of the pan. Does the design of the screen 94 80 F 3000 ft . 76 81 can force the crank forward, damaging the on the pickup tube create restrictions? We have seen engine thrust bearing.77736000 ft .80 F94 some pickup tube screen designs that restrict oil • Improperly installing the torque converter can force flow as much as 75%. Wire mesh is good. Perforated 94 40 F 0 ft . 84 89 the crank forward, damaging the engine thrust metal is usually restrictive. Measure the wire size and 94 120 F 0 ft . 78 83 bearing. This is most commonly caused by calculate the flow area. Most aftermarket screens improperly locating the torque convertor drain plug have less flow area than stock screens. in the flexplate. • If using a remote oil filter mount or oil cooler, As you can see by these examples, jet requirements can • If the torque converter balloons, it can force the make sure that all of the components are large vary a lot depending on fuel, altitude and temperature. crank forward, damaging the engine thrust bearing enough to eliminate any restrictions to oil flow. Oxygenated fuels are available in some states and can and the transmission. Most high-performance torque Many Cobra replica kit cars use components dramatically aff ect your jetting requirements. Make converters have anti-ballooning features. that are too restrictive. sure you get your jetting correct. Aviation fuel is lighter • Damage to the thrust bearing can happen • Undersize oil lines commonly restrict oil flow. and will require richening an engine in relationship to its in seconds! • The more bends/turns in an oiling system, requirement with pump gas. We have found in the dyno • Poorly designed remote filter mounts and ratio equals only a few percent less power. Running an MISCELLANEOUS PROBLEMSthe more restrictions are created.testing of our crate engines that 1 point richer on air/fuel adapters can create restrictions. engine as lean as possible produces the best power THAT CAN DAMAGE AN ENGINE • Be sure that the oil cooler flows enough oil but also increases combustion temperatures and • Dropping nuts, bolts, washers or foreign to meet the engine’s requirements. the chances of engine damage. materials down the intake. We have seen this more than once. • Never reuse a used oil cooler. Debris gets trapped and cannot be cleaned out. COMMON PROBLEMS WITH • Reusing an intake off an engine that had broken parts in a cylinder. The parts can get bounced up • Poorly designed oil filters can cause a restriction. FUEL DELIVERY SYSTEMS into the intake manifold, carburetor or air cleaner • Many oil systems only flow one way. Connecting the • Do not mount an EFI electric fuel pump so it has (pieces of piston or piston rings, etc.). When you remote oil filter or oil cooler lines backwards can to draw fuel from the tank. This creates negative put your used intake on your new engine and start cause engine damage/failure. pressure in the fuel line allowing the fuel to boil it, the pieces are drawn in and damage your engine. at a lower temperature. • Bead-blasting an EFI intake. You will NEVER get IGNITION SYSTEM CONSIDERATIONS/ • The pump must be mounted in the tank all of the blasting media out. When the engine is COMMON PROBLEMS or in a location so that it is gravity fed. started, it draws the blasting media into the • The ignition system must deliver a properly timed • If the fuel rail is too small and you have large cylinders, destroying the engine. spark. There are a lot of factors that determine when injectors, this can create a pulse in the fuel rail • Improperly torquing fasteners when installing new the spark should be delivered. The most common allowing fuel starvation on some cylinders. parts to your engine. Over-torquing of the intake factors include: compression ratio, fuel quality, fuel • Fuel should be pushed through the fuel filter. manifold bolts to the cylinder head on 302 and octane rating, combustion chamber design, engine Pulling fuel through a filter can cause cavitation. 351W engines can cause head gasket operating temperature, power adders such as NOS If a filter is to be used on the inlet of a rail-mounted sealing problems. or supercharger, inlet air temp, altitude and load. fuel pump, a filter rating of 160 microns MINIMUM • Installing distributor gears at the incorrect height, • Avoid too much or too little timing for your should be used. or using gears made of the wrong material. We engine combination. • It takes approx. 1/2 lb of gasoline to support have seen this a lot on remanufactured distributors • Avoid hooking up the vacuum advance to intake 1 hp. This is commonly referred to as a .5 BSFC. as well as popular aftermarket manufacturers manifold vacuum instead of ported vacuum. You should always err in the safe direction of of distributor assemblies. Use cast iron gears larger when sizing your injectors and fuel pump. for cast iron flat tappet cams, and steel gears for steel hydraulic roller cams. For important information about the proper usage of performance parts, please see page 14. 58 Techline (800) FORD788 See pages 286-292 for important safety, emissions and warranty information.


Ford Racing Catalogue Web
To see the actual publication please follow the link above