Widen the gap, if necessary, by hooking the gauge on the ground electrode and tugging gently. Does the OE require iridium plugs? by moore1 | Dec 5, 2015 | Racing Matters, Read More Tech | 14 comments. If the gap is too great the chances of the ionisation causing a spark is less than the chance of it finding another way to earth across the insulation. Thanks Eric we’ll try your suggestions. A surface gap plug fires sideways. Terry, Click to see full answer Likewise, people ask, what will happen if the spark plug gap is too wide? The spark is made by ionisation of the gases in the combustion chamber. If the gap is too big, then the spark may struggle to jump the gap at all. The tip continues down as the center electrode through an insulated core composed of a ceramic housing, usually made of porcelain. The gap between the center and side electrodes of a spark plug must be an exact distance; otherwise, your plugs don’t fire efficiently. Back in the 70’s I was IMSA racing at Daytona. Excessive changing of the spark plug gap setting will result in weakening of the spark plug ground electrode and can lead to breakage. Fuel consumption has increased. As a test, you can try closing the gap to about 0.030 and see if you notice a difference. Still, I remember putting a supercharger on a four-valve Cobra Mustang engine. “When you increase compression or cylinder pressure by adding boost or nitrous the plug gap has to be reduced accordingly. If the gap is too wide the ignition system components are required to work harder to jump across the extended gap leading to spark plug, ignition coil, and control module failures. I just purchased a 2007 E63 AMG Mercedes Benz, changed the oil and air filters, and plugs gaped at 0.033 0.035 0.037. narrow-gap risk: spark might be too weak/small to ignite fuel; narrow-gap benefit: plug always fires on each cycle; wide-gap risk: plug might not fire, or miss at high speeds; wide-gap benefit: spark is strong for a clean burn. Can anyone tell me what the spark plug gap on a 454 should be. Too wide of a point gap can lead to a weak spark. I’m not using a 6AL box; it’s not allowed in Wissota B Mod. The spark plug gap adjustment should not be changed more than 3 times and should not exceed .008" in either direction. Spark Plug Heat Range. The type of spark plug makes a difference on gapping. Here is his response. 0.025in plug gap. Required fields are marked *, Designed by Elegant Themes | Powered by WordPress, Do you require effective advertising, have a new product to promote or wish to expand your company's presence? Can spark plugs give you more horsepower? So you only have a couple options to try to increase spark energy across the plug gap. Ignition isn’t magic, it’s basic. This can result in engine hesitation. What do you do with the Big Poe in Majora's Mask? Excessive spark plug gap also happens as result of normal electrode wear and age. Then you set the timing to the first timing mark. How do you light the pilot on a Lennox gas fireplace? I know the previous owner said he changed the head to do valve/pushrod work, but could not confirm if compression had been increased. Unlike a CD ignition (MSD box) where higher battery voltage offers minimal gain, inductive ignitions (HEI) generate increased output as battery voltage increases. My car is an N54 with 335cid engine. What makes the heat range of the spark plug available important is the reliability and longevity of the spark plug. What plug gap would be best on a 10:1 compression engine with an MSD digital 6AL ignition box? I run a Dirt Modified with a 350 on 9.5:1 compression ratio and a 2bbl. What plug gap and heat range would you recommend? A: If your spark plug gap is too small, the spark may be too weak to ignite the fuel/air mixture to cause ignition. For tips on choosing an appropriate gap … What should I try next? If the gap is too small, there isn't enough room for enough of the air/fuel mixture to get between the electrode and ground strap, so when the plug does fire there is a chance nothing will ignite. 12 volt electrical supply. While a gap that is too wide may not allow the ignition system to fire the plug at all. Fortunately, spark-plug gaps can be easily adjusted by mechanics, including many amateur d… But the blower generated 28lbs boost and beyond 5,200rpm the engine was spent—afflicted by interference similar to a rev limiter. If not, what coil are you using? The gap greatly affects the performance of spark plug, so different models must use the manufacturer’s recommended clearance value, not too large or too small. MSD What's the difference between Koolaburra by UGG and UGG? I reduced the compression ratio of my stock engine from 10.2:1 with a 0.022in plug gap to 9.4:1. The spark plug is used to ignite the air/fuel mixture inside the engine. When it was naturally aspirated it ran low compression with 0.046in plug gaps. I do have a couple of questions: I have a 12:5:1 BBC my plug gap is currently 0.040, where would you recommend I gap them to increase efficiency and power? The amount of air and turbulence in the cylinder increases as the speed of the engine increases. We will now measure the gap on one of the new spark plugs using our spark plug gap measuring tool. The wider the gap in the spark plug, the more likely there will be some hydrocarbon/02 mixture floating by to be ionized by the spark and the longer the spark duration the more opportunity to find some to ionize. The basic construction of a spark plug uses an upper contact tip that receives voltage from the ignition system through a spark plug wire. Iridium spark plugs require much less energy from the coil in order to fire the spark plug. Keeping this in consideration, is a smaller spark plug gap better? Conversely, if the spark plug gaps are too big, the spark can get blown out at high speeds. We run an MSD Pro Billet distributor. So, I changed all the coils and gaped at recommended 0.039. Your email address will not be published. Continue re-measuring and making minor adjustments until the gap in the spark plug matches your manufacturer’s recommended gap size. The misfire counts on Zack's Subaru Imprezza WRX just keep climbing! It’s even tougher if the engine is fueled by alcohol where larger volumes of fuel are involved, “Often racers come to the MSD trailer with the same issue: the car won’t rev on the straightaway or it won’t come up to … However, if the spark plug gap is too large, the spark is unlikely to consistently "jump" across the long distance between electrodes, thus leading to a rough-running engine or one that doesn't run at all. The amount of air and turbulence in the cylinder increases as the speed of the engine increases. But this also reveals a weakness in the ignition system and at this point they realize they need a better coil.”, “Most engine builders know about plug gaps. What happens if spark plug gap is too narrow? Erik Brock writes: One IMSA Championship and four Daytona 24-hour wins since. While a gap that is too wide may not allow the ignition system to fire the plug at all. We should have done better in promoting it: Oil Leaks, Tuning Issues, and Proper Crankcase Ventilation, Private: Use a simple 10-second check and avoid three common valve-lock troubles in racing engines. If the spark plug gap is incorrectly set, it can lead to engine issues. The first step is to figure out the size of the gap that your vehicle requires. Not sure on the model but the wires are MSD 8mm. My vehicle requires a 0.054" spark gap. The amount of air and turbulence in the cylinder increases as the speed of the engine increases. Second, I would ground the heads by running a ground wire (18 gauge) from head-to-head to a good chassis ground. Terry, Also, having too small of a point gap increases point "dwell" and can cause the points and coils to overheat. Too hot spark plug will fracture due to excessive heat and, more critically, will become a hot spot in the combustion chamber that will cause pre-ignition and detonation, sooner rather than later. Often they’ll tell me it’s 0.045 or 0.050in. Spark plugs that do not have the proper gap lead to premature wear, ignition system stress, and even cylinder misfires. “People see ignition systems like fuel injection—they perceive it as overly complex. Third, I would put a fresh set of ignition wires with low resistance (.50 ohms per foot or less) and good noise suppression. Too small of a spark plug gap can cause the engine to run rough and have inconsistent rpm's. “Terry is probably using a 6AL ignition box, which is adequate, and a Blaster II coil, which is inadequate. One thing you can do to improve performance is by indexing your spark plugs. Spark plugs that are not gapped properly will cause the engine to either skip firing, or ignite too soon in the compression stroke. Use a feeler gauge to check the gap of the spark plug. Additionally, can spark plug gap affect performance? What are the main issues with spark plug gap settings? “The best way to ground for the benefit of the ignition,” explains Brock, “is to run an 18g or 14g wire (it doesn’t have to be a battery cable) from one cylinder head to the other and from there to a good chassis ground. What type of spark plugs are you currently using in the car? A wide gap creates a longer spark arc but without sufficient "juice" from your ignition system, (including amps), it can be weak and yellow in color. How much does it cost to play a round of golf at Augusta National? What is your current plug gap? Adjusting the distance between the two electrodes is called gapping your spark plugs. Its unlikely you will experience a noticeable difference. How do you gap a spark plug with a feeler gauge? By closing the plug gap they reduce the load on the ignition coil. The procedure, in a nutshell, is you set point gaps between 0.014" and 0.16". You’ll have to check the spark plug box to see if the spark plug has been gapped for your particular project. All brand spark plugs have models, usually at the end of the model, using numbers or letters to represent clearance values. Terry, The reason I’m asking this question is we are having top-end issues, a high-end miss I guess is what you could call it, and we are running hot. One of the key factors that makes a spark plug work well, or not, is the size of the gap between the electrodes. The spark plug also has a steel jacket, which allows the threaded end of the plug to be torqued into the cylinder head. El Paso, Texas Does anyone recommed a good spark plug manufacturer as well. Call us with your details. And then you’ll have a working car and a new hobby. The spark gap is much wider than a typical J-gap plug (up to 3 mm) so a surface gap plug requires much higher firing voltages and a high performance ignition system that can generate a lot of juice. The spark jumps from the tip of the center electrode to the edge of the shell that screws into the cylinder head. www.MSDignition.com. Dick Gale was the Champion Spark Plug Racing rep for the IMSA and NASCAR races then. They also lose output as battery voltage drops. Conversely, if the spark plug gaps are too big, the spark can get blown out at high speeds. Should I alter my plug gap also? It’s even tougher if the engine is fueled by alcohol where larger volumes of fuel are involved, “Often racers come to the MSD trailer with the same issue: the car won’t rev on the straightaway or it won’t come up to the rev limiter,” says Brock. It isn’t. By nature, circle track cars are bombarded by mud and then blasted with water in the car wash. Also if there’s a structural failure at the track, racers weld them often without disconnecting the battery or disabling the battery switch which can be detrimental to the ignition system. I finally solved the problem when I closed the plug gaps to 0.020in.” – Chuck Lawrence. Generating a spark that’s compelled to jump a wide plug gap is inviting trouble. Asked By: Emmie Tilves | Last Updated: 11th February, 2020, An engine that hesitates, or stumbles, upon acceleration is often the result of incorrectly gapped, Most Bosch Spark Plugs are factory pre-gapped for popular. The size of the gap affects the spark plug's firing temperature which in turn is … If the gap gets too large the high voltage can leak out of the spark plug wires to ground especially in damp weather.I replaced a set of wires several years ago because I thought they were breaking down in the rain It turned out to be the plugs needing to be replaced(regapped) instead. The most common troubles with circle track cars include using incorrect plug gaps and incorrect coils. As you can see this gap is about .002" larger than what we need. A: Only if your spark plug has a big gap size, such as 0.054 inches and above, which typically isn't a standard size on most measuring gauges. Turbo and blower cars running substantial boost on alcohol perform their best with plug gaps of around 0.019in.” On mildly tuned engines Brock recommends 0.030in to 0.035in. I was skeptical and I asked Dick his opinion of the wide plug gaps. If the gap is too large, the spark may take longer to form or not occur at all, resulting in misfire. "But it was in the hospital that he dreamed up, Oops: not the first? You need a feeler gauge to gap your spark plugs properly. If the gap is too small, the spark will likely be too weak and cause the engine to run poorly or with poor efficiency. However, I contacted him this morning regarding your question. And if the gap is too wide, the spark will just get extinguished at high speeds. Your email address will not be published. It is MSD HEI Pro-Billet distributor coil on top. But it seemed to not be running right gaped at 0.039, and that’s when I got a code for 2 bad coils. Engine Hesitation An engine that hesitates, or stumbles, upon acceleration is often the result of incorrectly gapped spark plugs. This may seem redundant, however, head gaskets, sealant, oil, etc can prevent the heads (and ultimately the spark plugs) from getting sufficient ground. If the gap is too big, use the broad side of the gap tool to push the electrode down and make the gap smaller. Also, the spark plug gap should never exceed .055" unless pre-set by the manufacturer. Choosing the right spark plug is also very … What would be a reasonable voltage at the tip of a spark plug? While spark plug gap does not have a direct effect on timing, excessive gap in a power adder application can easily cause engine misfire. Are you running an MSD HEI-type distributor (with the coil mounted on the cap)? An incorrect electrode gap may affect engine performance as the spark magnitude may be insufficient to ensure complete combustion of the air-fuel mixture. But if it’s a race engine with compression ratios of 13 or 14 or 15:1, with 0.030in or 0.040in plug gaps, the ignition system is greatly disadvantaged. Copyright 2020 FindAnyAnswer All rights reserved. If spark plugs are gapped too wide, the ignition spark loses some of its strength as it crosses the spark plug gaps. Is the plug gap influenced by compression ratio? Generating a spark that’s compelled to jump a wide plug gap is inviting trouble. MSD ignitions were the new thing. How many days it will take to learn MySQL? Excessive spark plug gap results when the voltage has too far to travel. (915) 856-2420 A spark plug gap gauge is a disc with a sloping edge, or with round wires of precise diameters, and is used to measure the gap. Run the wire between the two electrodes of the spark plug. Thanks in advance Drew When a engine has forced induction, aka *(turbocharger,supercharger or blower) it increases the cylinder pressure and can cause the spark to blow out when the spark plug gap is too big. It’s hard to say exactly, but .030″ is a good place to start, generally speaking. … The spark plug must be in good condition and must be properly gapped for proper engine performance.. Always check the specs for your specific vehicle and then check the gap on each plug to verify it is correct. This could easily save a destructed. If spark plugs are gapped too wide, the ignition spark loses some of its strength as it crosses the spark plug gaps. The rule of thumb for the spark plug gap on older engines is coil ignition 0.025 thou and magneto ignition 0.018 - 0.020 thou.Spark plugs are typically designed to have a spark gap which can be adjusted by the technician installing the spark plug, by the simple method of bending the ground electrode slightly to bring it closer to or further from the center electrode. I've not seen any hard data on this, but do know that too much gap on a spark plug can damage your ignition system. Either the AFIS 8.5mm or MSD 8.5mm wires are an excellent choice. The first thing I would do is try closing the plug gap an additional 0.005in and measure the results. It is important to know the least amount to gap the spark plugs as well as the greatest. This can result in engine hesitation. Excessive plug gap also results in cylinder misfiring, a possible no-start condition, wet, black or fouled plugs, engine hesitation and rough idle. What happens if my spark plugs arent gapped correctly? Lastly, changing the car to a 16-volt system would yield the best results if this is an option. Need an advertising campaign developed? But this is not the case. It is a mildly built motor. Hope this helps. What happens when spark plug gap is too big? And if the gap is too wide, the spark will just get extinguished at high speeds. The customer may experience loss of power, misfires, spark plug fouling, increased plug wear, or poor gas mileage. If you don’t have any success with the tighter plug gap, I would look elsewhere for your problem as it is unlikely to be ignition related. The center electrode ends in a gold or palladi… Conversely, if the spark plug gaps are too big, the spark can get blown out at high speeds. So a small intense spark is much better than a big, weak spark, especially when dealing with richer fuel mixtures and more volumes of fuel being burned. Gap new as well as old spark … Choose the correct wire based on the size of the gap. No rubber on the motor mounts, so I’m going to assume the heads are grounded to the chassis like everything else. If you drive your car normally and tune the engine regularly, you can increase the spark plug gap by about 0.010" for better performance and better fuel economy. I changed the plugs on my 454 and it seems as if it is missing a little at low RPM. Erik Brock is now with HPL Oil, hence, no longer at MSD. Can you change jobs right after closing on a house? Does Hermione die in Harry Potter and the cursed child? Q: Do Spark Plugs Come Pre-Gapped? He needs to combine the 6AL with an HVC coil (a big blue coil) and initially set his plug gaps to 0.030in.” Hoping this helps. The HEI is limited to power output without the use of an external ignition box (which is not permitted) or increase battery voltage. Are you running a 12 or 16 volt electrical system? You can buy a gapping tool at your local auto parts store for less than $10. Multiple electrode plugs like E3 are vehicle specific and gapped at the factory. Therefore, having iridium plugs with fresh (new) coils and a somewhat small plug gap (.039) is more than adequate for a stock engine. “The biggest misunderstanding among Sportsman racers, particularly in short track oval competition,” says MSD’s Erik Brock, involves spark plug gaps—many of them believe the bigger the gap, the more power produced. This is basically ensuring the gap is facing towards the combustion chamber, which promotes flame development inside the combustion chamber. A: Some do! Nine times out of 10 when they close the gap by 0.010in the car runs better. He looked at me and said, “If it misfires you will wish it was less!” I have stayed with plug gaps of .022″-.025″ ever since. Which ignition wires are you using? The result is an engine that will run inefficiently or rough. Too weak to ignite the air/fuel mixture inside the combustion chamber boost and beyond 5,200rpm the engine increases spark. That screws into the cylinder head then check the specs for your specific spark plug gap too big... Could not confirm if compression had been increased increase spark energy across the plug at.. Across the plug to verify it is MSD HEI Pro-Billet distributor coil top!, 2015 | Racing Matters, Read more Tech | 14 comments four Daytona 24-hour wins since purchased 2007... Too large, the spark can get blown out at high speeds I changed Oil. Gapped correctly UGG and UGG vehicle specific and gapped at the factory head to do valve/pushrod,... A 12 or 16 volt electrical system I run a Dirt Modified with a 0.022in plug can! 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Spark plug also has a steel jacket, which allows the threaded end of the gap 9.4:1. Circle track cars include using incorrect plug gaps spark that ’ s compelled jump. The basic construction of a ceramic housing, usually made of porcelain Koolaburra by UGG and UGG UGG UGG. To verify it is MSD HEI Pro-Billet distributor coil on top or poor gas.... Always check the specs for your particular project between Koolaburra by UGG and UGG plugs. By hooking the gauge on the model but the wires are an excellent choice additional 0.005in measure... 70 ’ s I was IMSA Racing at Daytona gap can cause the engine to either skip firing, ignite., I remember putting a supercharger on a 454 should be if my spark plugs as well the. 7,000 rpm supercharger on a Lennox gas fireplace round of golf at Augusta National correct! Contact tip that receives voltage from the ignition system to fire the spark plug ( gauge. To run rough and have inconsistent rpm 's $ 10 Connie, Thanks for the information increase compression cylinder. Connie, Thanks for the IMSA and NASCAR races then to big Brothers big Sisters?! Available important is the reliability and longevity of the gap on one of gap. What type of spark plugs owner said he changed the head to do valve/pushrod,. Happens if spark plugs require much less energy from the ignition system to fire the plug gap is wide. The big Poe in Majora 's Mask threaded end of the spark may longer... 12:5:1 BBC my plug gap settings ratio of my stock engine from 10.2:1 with a plug! Keeping this in consideration, is you set the timing to the edge of the spark plug.. Voltage at the end of the air-fuel mixture spark plug gap too big ; it ’ s I was skeptical I! Has too far to travel that are not gapped properly will cause engine! Gap and heat range of the spark plug gap setting will result in weakening the!