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Don’t Lose Your Head...

Don’t lose your head gaskets without good reason... ... or at least knowing why!

The biggest reason for losing a head gasket is detonation or pre-ignition.

What is detonation?

Detonation, or spark knock, is an erratic form of combustion which occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to auto ignite. This causes multiple flame fronts that collide and produce a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knock noise. The hammer-like shock wave created by detonation subject the head gasket, piston , rings, sparkplugs and rod bearings to severe overload.

What is Pre-ignition?

Instead of fuel igniting at the right instant to give the crankshaft a smooth kick in the right direction, the fuel ignites prematurely (early) causing a momentary backlash as the piston tries to turn the crank in the wrong direction.

Both detonation and pre-ignition are damaging to your engine, but are caused in a slightly different way. Also, pre-ignition may cause detonation, but not the opposite. Pre-ignition is caused by "hot spots" in the combustion chamber. A sharp edge in the chamber or on the piston and/or sharp edges on valves will cause this condition. Low coolant levels or other cooling system problems that cause the engine to run hotter than normal will cause pre-ignition as well as detonation. Fortunately for most of you with gauges, you can monitor this cause before the effect takes place. Too hot a spark plug heat range will overheat the spark plug and cause the same result. What’s more difficult to directly monitor and also most common? Carbon deposits. Carbon deposits accumulate in the combustion chamber and on the top of pistons to increase compression to the point where detonation becomes a problem. Carbon deposits are common cause of pre-ignition and detonation in high-mileage engines. Worn valve guides and seals, worn or broken rings, and/or cylinder wear can all lead to oil consumption and thick carbon build-up. Remember that your Turbo regal is now 10 to 13 years old. Also note that infrequent driving can also accelerate build-up of deposits; just so the low mileage owners don’t think they’re exempt from any problems.

Now that we have established the reasons for detonation and pre-ignition and that they are the major reason for head gasket failure and engine damage, what do we do with this vital information? There are a handful of common sense and not so common sense answers.

1. Try a higher octane fuel The octane rating of a given grade of gasoline is a measure of it’s detonation resistance. Heavy engine loads, high compression ratios, and of coarse turbocharged engines may require a high octane rating. A turbocharged engine, under boost conditions, can reach compression ratios as high as 18:1. If changing to a higher octane rating does not correct the problem then continue your search. Consider that anything that increases the normal combustion temperatures or pressures, leans out the air/fuel mixture, or causes the engine to run hotter than normal, can cause detonation.

2. Check for loss of EGR Although the Exhaust Gas Recirculation System is one of the engines primary emission controls, it has a cooling effect on the combustion temperatures by diluting the air/fuel mixture slightly. Lowering the combustion temperatures reduces the formation of NOX (pollutant) as well as the octane requirements of the engine. If the EGR valve is not opening, the cooling effect is lost. The result is higher combustion temperature under load and an increased chance for detonation. In some cases an EGR malfunction will cause poor driveability which will even damage the head gasket or cause damage to the pistons or valves. Other cases, when the EGR does not work at all, the combustion chamber can become extremely hot, as much as 4500°, even with a satisfactory cooling system.

Sidebar: Before you condemn the EGR valve, perform an analysis to verify the EGR is receiving the signal. The Grand National uses a solenoid to open and close the EGR valve. The solenoid is toggled by signals from the ECM which acts accordingly to signals received from various sensors on the engine.

3. Keep compression within reasonable limits When engines are remanufactured, clean cuts to the head and/or decking of the block, the cc’s of the chamber are reduced and result in higher compression. 9:1 is as high as a street vehicle should go on pump gas. You need to consider the amount of boost pressure that you will run on the application. In most cases, turbocharged applications should have 8:1 compression or less, once again, depending on boost.

4. Over Advanced Ignition Timing Too much spark advance programmed into the computer chip can cause cylinder pressure to rise too rapidly. ESP Products’s Dyno computer chip uses stock ignition timing and increases the boost pressure from 15-17 psi. This will provide an adequate increase in power without risk of detonation. (With products like Boost Valve Kits and Adjustable Wastegate Actuator being able to control the boost levels independently, more attention should be placed on the timing and fuel curves rather than boost levels.) The Street Lethal starts off with 28° timing and tapers it down to 24° by 4500 rpm. This, along with modified fuel curves, fan control, and rev limiter, makes this chip reliable for street application with minimal risk of detonation on 93-94 octane ratings. Eastern’s Blaster computer chip is designed for track use only and for use with 115 octane or better. The higher octane rating is due to the 36° ignition timing which is then tapered down to 28° and about 4500 rpm. With this more aggressive timing curve the Blaster offers a 25+ horsepower increase over the Street Lethal when used in the proper application. The timing taper helps lower the combustion temperature and pressure and allow the engine to produce more horsepower resulting in more top end mph.

5. Read your plugs The wrong heat range will cause detonation as well as pre-ignition. Too hot a heat range will cause the insulator around the electrode to yellow and blister. Copper core plugs generally have a broader heat range than ordinary plugs, which lessens the danger of detonation.

Note: We recommend, for the turbo Regal, to stay away from all platinum and specialty spark plugs. The higher the engine output, the cooler the spark plug.

6. Check for overheating A hot engine is more likely to suffer spark knock than one which operates at normal temperature. Look for a bad water pump, too hot a thermostat, and insufficient radiator size/ fan size.

7. Check for a lean fuel mixture A rich mixture resists detonation while lean ones do not. Air leaks in the inlet, intake manifold gaskets, sub-standard sensors (TPS, MAF,O2, and others) allow extra air into the engine and lean out the mixture; don’t forget dirty fuel injectors. The life cycle of an automotive fuel injector is 50,000 miles. Many Turbo Regal owners are driving with 90,000+ miles on their injectors.

8. Remove carbon deposits Carbon deposits will have an insulating effect that slows the normal transfer of heat away from the combustion chamber in the head. A thick layer of deposits can therefore raise the combustion temperatures and contribute to "pre-ignition" as well as detonation. The accumulation of carbon deposits in the combustion chamber and on the top of the pistons can increase compression to the point it becomes a problem.

Carbon deposits can be removed by using a chemical "top cleaner". This type of product is poured into the throttle body of an idling vehicle. Engine is shut off so the chemical can take effect and when re-started the deposits are blown out of the combustion chamber.

9. check the boost pressure; finally, our favorite... Controlling the amount of boost is absolutely critical to prevent detonation. Too much boost will destroy head gaskets as well as the engine in no time if not corrected.

Improved intercooling can help reduce detonation under boost. The intercooler’s job is to lower the air temperature (charged) after it leaves the compressor. Installing a larger or more efficient intercooler can eliminate detonation worries while allowing the engine to safely handle more boost.

As a comparison, the stock intercooler operates at 70% efficiency in the stock application. ESP Products’s Frontmount intercooler operates at over 95% efficiency in applications over 550 horsepower, and has supported stock engines pushing 700+ horsepower.

NEW PRODUCT ANNOUNCEMENTS

Through the R & D time invested in the "Big Brother" motor, featured in the May issue of High Tech Performance magazine, ESP Products has fine tuned some new products for the ESP product line.

First and foremost is the engine block girdle. The prototype installed in the motor was exactly that, rough and crude. ESP Products has since refined the manufacturing process by having the ESP Engine Girdle fabricated on a CNC machine. Developed and perfected on CAD software, the engine girdle requires no modifications to the oilpan. The main caps must be ground down and clearanced by a skilled machine shop. All hardware (main studs, oilpan studs, oil pick-up, and gaskets) is included with the ESP Engine Girdle kit.

At the other end of the drivetrain is the differential. Under extreme use, the rear end gears and the bearings endure the same stress and punishment as the main caps and bearings. For these demanding applications the Ultimate Differential Girdle is introduced. You can now pre-load the differential caps to eliminate premature bearing wear and gear breakage. Along with the added strength of the girdle you have the convienent oil drain and fill wholes in the rear of the cover. The ultimate differential girdle is rated at over 6-tons of support strength. This product also allows you to add their axle brace kit for additional strength. Being independently adjustable, they provide even tire wear and also relieves stress on the axles and bearings.

Not all of the new items on the market are heavy duty racing products. Casper electronics has developed a few very much needed electronic tools. ESP Products’s tech. line is constantly receiving calls by customers wanting to know how to set their cam sensor. Casper electronics has made this very easy for us to answer. "Buy part number1930 for only $29.99." This Cam Sensor Setting Tool makes installation much easier. Simply plug it into your cam sensor and watch the tool do the rest.... not literally.

The most innovative new product to hit the market would definitely be the Ignition Coilpack Simulator. This piece of equipment is very helpful when diagnosing a weak coilpack or showing a comparison between a stock coil and the ESP High Output Coilpack. Plus it’s a ball to watch. Disconnect the harness from the ignition module and snap the simulator on top of your coilpack. Connect to the vehicles battery and turn it on. With a twist of the knob you can simulate engine rpm from 400 to 8000 rpms. Most coils will test fine with no load, but always fail under heavy load. ESP has taken coils that were thought to be good and checked them with the Coilpack simulator and noted spark failure at 6000 to 7000 rpm. This example will operate fine on a daily driver that rarely sees the track or full throttle, but under heavy load the battery weakens and coilpack failure is certain.

Ready, SETTINGS, Go

Every day we answer questions on how to set various engine sensors; Cam sensor, Crank sensor Idle Air Control (IAC) Valve, Throttle Position Sensor (TPS), and so on. All the sensors need to be in excellent operating condition in order to extract peak performance from your engine. The non-adjustable sensors should be periodically inspected to be sure they are within factory specifications. Coolant temperature, Mass Air Flow, and EGR to name a few.

The Crank sensor requires no adjustment, but must be set properly the first time or it will have contact with the interuptor ring on the harmonic balancer. Over time this sensor may loosen and will occasionally need to be tightened. To do so you need a feeler gauge. The feeler gauge can be plastic, brass, or paper. When setting the crank shaft sensor on your engine DO NOT USE A METAL FEELER GAUGE to measure the clearances. The sensor is magnetic and the metal gauge will damage the Crank sensor. The clearance should be at 14-16 thousandths. There, that was easy enough.

To set the Camshaft sensor you must first rotate the #1 piston to 25° after top dead center, this is on the compression stroke. First find top dead center, make the balancer, measure 36 mm and rotate in the clockwise direction. This should get you to 25° after TDC. Once you have arrived at this point, see new product information and the Cam Sensor Setting Tool.

Two down and two to go. The next two sort of go together and we will explain them that way. This process is referred to as setting the minimum air rate. First, ground your ALDL,located under the radio, by installing a paperclip into the upper two right hand terminals. (This is also how you check your trouble codes) Next turn the key on, engine off. Wait 20-30 seconds and then unplug your AIC valve. Now turn the key off and unground the computer. Start the engine. It should idle at about 600-800 rpm; if not, adjust the throttle stop on the throttle body, on the driver’s side of the engine. If the engine stalls, try to keep it running by hand with the throttle linkage. Once you have established an acceptable idle it is time to re-test the TPS sensor.

With a screw driver or 5/16" nut driver, loosen the two screws holding the TPS in place. Note that there are two slotted holes at these screws. Push the lower portion of the sensor as far forward as possible and keep constant pressure on it. With a digital volt-meter, you need to adjust the upper portion of the sensor to obtain a voltage reading of .46-.48. All the while keeping the lower portion forward. ( Probe the "B" &"C" wires of the TPS) Now tighten and check idle voltage again and then W.O.T. W.O.T. should be in the 4.6-4.8 range. If the W.O.T. setting is not within the above range then try again. If you still have trouble, the sensor may be defective. Once you achieve the proper settings on the TPS, plug the IAC back in and start the engine. Idle should be smooth and steady at 900-1000 rpms. This should also eliminate any intermittant stalling when you take your foot off the gas pedal. If the engine still tries to search for an idle, try again or your IAC sensor may be defective.


Tech Tips
	*Don’t Lose Your Head...* Don’t lose your head gaskets without good reason... ... or at least knowing why! The biggest reason for losing a head gasket is detonation or pre-ignition. *What is detonation?* Detonation, or spark knock, is an erratic form of combustion which occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to auto ignite. This causes multiple flame fronts that collide and produce a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knock noise. The hammer-like shock wave created by detonation subject the head gasket, piston , rings, sparkplugs and rod bearings to severe overload. *What is Pre-ignition?* Instead of fuel igniting at the right instant to give the crankshaft a smooth kick in the right direction, the fuel ignites prematurely (early) causing a momentary backlash as the piston tries to turn the crank in the wrong direction. Both detonation and pre-ignition are damaging to your engine, but are caused in a slightly different way. Also, pre-ignition may cause detonation, but not the opposite. Pre-ignition is caused by "hot spots" in the combustion chamber. A sharp edge in the chamber or on the piston and/or sharp edges on valves will cause this condition. Low coolant levels or other cooling system problems that cause the engine to run hotter than normal will cause pre-ignition as well as detonation. Fortunately for most of you with gauges, you can monitor this cause before the effect takes place. Too hot a spark plug heat range will overheat the spark plug and cause the same result. What’s more difficult to directly monitor and also most common? Carbon deposits. Carbon deposits accumulate in the combustion chamber and on the top of pistons to increase compression to the point where detonation becomes a problem. Carbon deposits are common cause of pre-ignition and detonation in high-mileage engines. Worn valve guides and seals, worn or broken rings, and/or cylinder wear can all lead to oil consumption and thick carbon build-up. Remember that your Turbo regal is now 10 to 13 years old. Also note that infrequent driving can also accelerate build-up of deposits; just so the low mileage owners don’t think they’re exempt from any problems. Now that we have established the reasons for detonation and pre-ignition and that they are the major reason for head gasket failure and engine damage, what do we do with this vital information? There are a handful of common sense and not so common sense answers. 1. Try a higher octane fuel The octane rating of a given grade of gasoline is a measure of it’s detonation resistance. Heavy engine loads, high compression ratios, and of coarse turbocharged engines may require a high octane rating. A turbocharged engine, under boost conditions, can reach compression ratios as high as 18:1. If changing to a higher octane rating does not correct the problem then continue your search. Consider that anything that increases the normal combustion temperatures or pressures, leans out the air/fuel mixture, or causes the engine to run hotter than normal, can cause detonation. 2. Check for loss of EGR Although the Exhaust Gas Recirculation System is one of the engines primary emission controls, it has a cooling effect on the combustion temperatures by diluting the air/fuel mixture slightly. Lowering the combustion temperatures reduces the formation of NOX (pollutant) as well as the octane requirements of the engine. If the EGR valve is not opening, the cooling effect is lost. The result is higher combustion temperature under load and an increased chance for detonation. In some cases an EGR malfunction will cause poor driveability which will even damage the head gasket or cause damage to the pistons or valves. Other cases, when the EGR does not work at all, the combustion chamber can become extremely hot, as much as 4500°, even with a satisfactory cooling system. Sidebar: Before you condemn the EGR valve, perform an analysis to verify the EGR is receiving the signal. The Grand National uses a solenoid to open and close the EGR valve. The solenoid is toggled by signals from the ECM which acts accordingly to signals received from various sensors on the engine. 3. Keep compression within reasonable limits When engines are remanufactured, clean cuts to the head and/or decking of the block, the cc’s of the chamber are reduced and result in higher compression. 9:1 is as high as a street vehicle should go on pump gas. You need to consider the amount of boost pressure that you will run on the application. In most cases, turbocharged applications should have 8:1 compression or less, once again, depending on boost. 4. Over Advanced Ignition Timing Too much spark advance programmed into the computer chip can cause cylinder pressure to rise too rapidly. ESP Products’s Dyno computer chip uses stock ignition timing and increases the boost pressure from 15-17 psi. This will provide an adequate increase in power without risk of detonation. (With products like Boost Valve Kits and Adjustable Wastegate Actuator being able to control the boost levels independently, more attention should be placed on the timing and fuel curves rather than boost levels.) The Street Lethal starts off with 28° timing and tapers it down to 24° by 4500 rpm. This, along with modified fuel curves, fan control, and rev limiter, makes this chip reliable for street application with minimal risk of detonation on 93-94 octane ratings. Eastern’s Blaster computer chip is designed for track use only and for use with 115 octane or better. The higher octane rating is due to the 36° ignition timing which is then tapered down to 28° and about 4500 rpm. With this more aggressive timing curve the Blaster offers a 25+ horsepower increase over the Street Lethal when used in the proper application. The timing taper helps lower the combustion temperature and pressure and allow the engine to produce more horsepower resulting in more top end mph. 5. Read your plugs The wrong heat range will cause detonation as well as pre-ignition. Too hot a heat range will cause the insulator around the electrode to yellow and blister. Copper core plugs generally have a broader heat range than ordinary plugs, which lessens the danger of detonation. Note: We recommend, for the turbo Regal, to stay away from all platinum and specialty spark plugs. The higher the engine output, the cooler the spark plug. 6. Check for overheating A hot engine is more likely to suffer spark knock than one which operates at normal temperature. Look for a bad water pump, too hot a thermostat, and insufficient radiator size/ fan size. 7. Check for a lean fuel mixture A rich mixture resists detonation while lean ones do not. Air leaks in the inlet, intake manifold gaskets, sub-standard sensors (TPS, MAF,O2, and others) allow extra air into the engine and lean out the mixture; don’t forget dirty fuel injectors. The life cycle of an automotive fuel injector is 50,000 miles. Many Turbo Regal owners are driving with 90,000+ miles on their injectors. 8. Remove carbon deposits Carbon deposits will have an insulating effect that slows the normal transfer of heat away from the combustion chamber in the head. A thick layer of deposits can therefore raise the combustion temperatures and contribute to "pre-ignition" as well as detonation. The accumulation of carbon deposits in the combustion chamber and on the top of the pistons can increase compression to the point it becomes a problem. Carbon deposits can be removed by using a chemical "top cleaner". This type of product is poured into the throttle body of an idling vehicle. Engine is shut off so the chemical can take effect and when re-started the deposits are blown out of the combustion chamber. 9. check the boost pressure; finally, our favorite... Controlling the amount of boost is absolutely critical to prevent detonation. Too much boost will destroy head gaskets as well as the engine in no time if not corrected. Improved intercooling can help reduce detonation under boost. The intercooler’s job is to lower the air temperature (charged) after it leaves the compressor. Installing a larger or more efficient intercooler can eliminate detonation worries while allowing the engine to safely handle more boost. As a comparison, the stock intercooler operates at 70% efficiency in the stock application. ESP Products’s Frontmount intercooler operates at over 95% efficiency in applications over 550 horsepower, and has supported stock engines pushing 700+ horsepower. NEW PRODUCT ANNOUNCEMENTS Through the R & D time invested in the "Big Brother" motor, featured in the May issue of High Tech Performance magazine, ESP Products has fine tuned some new products for the ESP product line. First and foremost is the engine block girdle. The prototype installed in the motor was exactly that, rough and crude. ESP Products has since refined the manufacturing process by having the ESP Engine Girdle fabricated on a CNC machine. Developed and perfected on CAD software, the engine girdle requires no modifications to the oilpan. The main caps must be ground down and clearanced by a skilled machine shop. All hardware (main studs, oilpan studs, oil pick-up, and gaskets) is included with the ESP Engine Girdle kit. At the other end of the drivetrain is the differential. Under extreme use, the rear end gears and the bearings endure the same stress and punishment as the main caps and bearings. For these demanding applications the Ultimate Differential Girdle is introduced. You can now pre-load the differential caps to eliminate premature bearing wear and gear breakage. Along with the added strength of the girdle you have the convienent oil drain and fill wholes in the rear of the cover. The ultimate differential girdle is rated at over 6-tons of support strength. This product also allows you to add their axle brace kit for additional strength. Being independently adjustable, they provide even tire wear and also relieves stress on the axles and bearings. Not all of the new items on the market are heavy duty racing products. Casper electronics has developed a few very much needed electronic tools. ESP Products’s tech. line is constantly receiving calls by customers wanting to know how to set their cam sensor. Casper electronics has made this very easy for us to answer. "Buy part number1930 for only $29.99." This Cam Sensor Setting Tool makes installation much easier. Simply plug it into your cam sensor and watch the tool do the rest.... not literally. The most innovative new product to hit the market would definitely be the Ignition Coilpack Simulator. This piece of equipment is very helpful when diagnosing a weak coilpack or showing a comparison between a stock coil and the ESP High Output Coilpack. Plus it’s a ball to watch. Disconnect the harness from the ignition module and snap the simulator on top of your coilpack. Connect to the vehicles battery and turn it on. With a twist of the knob you can simulate engine rpm from 400 to 8000 rpms. Most coils will test fine with no load, but always fail under heavy load. ESP has taken coils that were thought to be good and checked them with the Coilpack simulator and noted spark failure at 6000 to 7000 rpm. This example will operate fine on a daily driver that rarely sees the track or full throttle, but under heavy load the battery weakens and coilpack failure is certain. *Ready, SETTINGS, Go* Every day we answer questions on how to set various engine sensors; Cam sensor, Crank sensor Idle Air Control (IAC) Valve, Throttle Position Sensor (TPS), and so on. All the sensors need to be in excellent operating condition in order to extract peak performance from your engine. The non-adjustable sensors should be periodically inspected to be sure they are within factory specifications. Coolant temperature, Mass Air Flow, and EGR to name a few. The Crank sensor requires no adjustment, but must be set properly the first time or it will have contact with the interuptor ring on the harmonic balancer. Over time this sensor may loosen and will occasionally need to be tightened. To do so you need a feeler gauge. The feeler gauge can be plastic, brass, or paper. When setting the crank shaft sensor on your engine DO NOT USE A METAL FEELER GAUGE to measure the clearances. The sensor is magnetic and the metal gauge will damage the Crank sensor. The clearance should be at 14-16 thousandths. There, that was easy enough. To set the Camshaft sensor you must first rotate the #1 piston to 25° after top dead center, this is on the compression stroke. First find top dead center, make the balancer, measure 36 mm and rotate in the clockwise direction. This should get you to 25° after TDC. Once you have arrived at this point, see new product information and the Cam Sensor Setting Tool. Two down and two to go. The next two sort of go together and we will explain them that way. This process is referred to as setting the minimum air rate. First, ground your ALDL,located under the radio, by installing a paperclip into the upper two right hand terminals. (This is also how you check your trouble codes) Next turn the key on, engine off. Wait 20-30 seconds and then unplug your AIC valve. Now turn the key off and unground the computer. Start the engine. It should idle at about 600-800 rpm; if not, adjust the throttle stop on the throttle body, on the driver’s side of the engine. If the engine stalls, try to keep it running by hand with the throttle linkage. Once you have established an acceptable idle it is time to re-test the TPS sensor. With a screw driver or 5/16" nut driver, loosen the two screws holding the TPS in place. Note that there are two slotted holes at these screws. Push the lower portion of the sensor as far forward as possible and keep constant pressure on it. With a digital volt-meter, you need to adjust the upper portion of the sensor to obtain a voltage reading of .46-.48. All the while keeping the lower portion forward. ( Probe the "B" &"C" wires of the TPS) Now tighten and check idle voltage again and then W.O.T. W.O.T. should be in the 4.6-4.8 range. If the W.O.T. setting is not within the above range then try again. If you still have trouble, the sensor may be defective. Once you achieve the proper settings on the TPS, plug the IAC back in and start the engine. Idle should be smooth and steady at 900-1000 rpms. This should also eliminate any intermittant stalling when you take your foot off the gas pedal. If the engine still tries to search for an idle, try again or your IAC sensor may be defective.