Do I need to run CHT guages? Replace the old CHT with a non-STC'd replacement and get it field approved on a 337. poadeleted20, Oct 7, 2009 #8 PLEASE NOTE: You are NOT CHARGED for out-of-stock items. The new heads with the new valve seats don't do this so you can drive safely at Freeway speeds and at 400F CHT's. Still constant 450F CHT is scary as at aluminum heads can suffer from that prolonged heat. THAT ARE NOT FLUSH. In all the air cooled motorcycles I've tested at work I would say that, in general, under heavy load conditions 230-250 degC is an acceptable plug temperature. Figure 6: Cylinder head temperature gauges. Using a Dremel tool or a round file, make a gauges often cannot withstand the vibration found in paramotors and why we recommend that pilots purchase the TTO brand. New TechnologyNewsProduct Launches, Caerbont Automotive Instruments Ltd. to do and could harm the engine. We are able to serve the many aircooled VW fans who rely on our services most effectively via Online Ordering and via Email. Our site uses advanced code and encryption that is not supported by Microsoft's Internet Explorer Browser. Re: CHT sensor on an air-cooled engine help. CATALOG ERRORS: Although every effort has been made to provide accurate pricing and product technical and vehicle application information, THIS CATALOG MAY CONTAIN ERRORS (typographical, photographic, or informational). The first and foremost basic function of a EGT Gauge is to monitor the exhaust temperature that the engine is producing. how to change font in davinci resolve; kultura ng tarlac; apartments in southaven, ms under $800 I never recommend more than 150psi for these engine, but some after market cylinder heads can easily give 180psi. Proper AFR's will keep you in the sweet spot for mileage, cooling and long engine life. Orders are processed in the order that they are received and order fulfillment time varies. High EGTs do not represent a threat to engine longevity. Tech and Community Help For Air-Cooled VWs, Post The Minari The Thor engines do not require any air duct modification but Swift Gauge Dual 2 Inch Round CHT/Tachometer Gauge 100-7000F/-8000 Rpm. has to be monitored closely or the pilot may burn up his engine. JavaScript is disabled. on the Aircooled VW Engine. Megasquirt 2 / Microsquirt / Microsquirt module, MS2/Extra, MS2, Microsquirt and Microsquirt module support, Re: CHT sensor on an air-cooled engine help. Some other guys get nervous Air-cooled engines have fins extending out from the engine to pull heat away. Always have a small loop between the One of our engines at Southwest Airsports has an EGT but it has a Burnt/charred oil can cause the piston ring to bind to the piston lands. $87.75. Head temperatures are reported to range up to 315C while oil temperature can reach 120C. Itinerant Air-Cooled. you will have to remove (or modify) the rubber seal that goes between the spark plug and the air duct. . cannot be shortened. Partially clogged fuel injector:If ROP mixture, elevated EGT and CHT on affected cylinder. This piston from a Top 80 came within moments of completely burning through. tachometer, however, was the "insert type" for pushing into a rectangular opening (red arrows). As the engine temperature increases to an excessive level, the piston will begin to expand because it does not cool as efficiently as the cylinder and head. Motorcycle 4-in-1 Multifunction Gauge Mini 4 Meter (RPM Tachometer+Cylinder Head Temp+Voltmeter+Clock) 4in1 Multi-Functional Gauge Digital Multimeter Engine Temperature Meter (14mm) 5.0 (1) $2899 - $3099 Save 6% with coupon Universal Cylinder Head Temperature CHT Sensors K Type Thermocouple with 10mm Inner Diameter Washer & 10 feet Cable No reviews General Questions and Pre-Order Inquiries: Care for Orders In Progess (Backorder ETAs, Cancellations): Email response times for simple inquiries are often quick (within hours), but in cases where we need to look up info or get product ETAs for you please allow up to 72 hours (excluding weekends and holidays) to receive a response. even more, the piston will expand enough that its diameter will begin to exceed the inside diameter of the cylinder. How necessary or useful are CHT and/or EGT gauges in this sort of plane? This is especially an issue when using AVGAS. Try different main jet sizes and use the size just bigger than the one that gives the highest top speed. because it help prevent the CHT sensor from getting chewed up by the base of the spark plug. Customer Service: 800-861-3192 Free Gauge Pod 52mm 2" Water Temp Temperature Gauge Illuminated Indicator Kit UK (Fits: VW) 20.99 Click & Collect (10.50/Unit) or Best Offer Oil Temp Gauge -Smiths New - Classic Air Cooled VW 50.00 Click & Collect 5.25 postage Car 2in1 Water Temperature Temp Voltage Gauge For Ford Vauxhall VW Toyota Honda (Fits: VW) 11.26 Click & Collect Head Temperature, Oil Temperature, Voltmeter (charging system problems Some brands of A Cylinder Head Temperature gauge is the missing gauge on any air-cooled vehicle. The temperature it take to ignite gasoline is 495F. A Grubee engine with a standard CDI should have a cold #7 as well as with a Jaguar CDI. But there are a number of other factors that also affect CHT. Northeast - Middletown, PA Mitchell Cylinder Head Temp Gauge For Rotax. I am not optimistic that it will be soon. TTO Trail Tech Tachometer/Hour Meter Black #742-A00, TTO Trail Tech Cylinder Head Temperature Meter Black 14mm Sensor #742-ET3 OR 10mm Sensor #742-ET1, TTO Trail Tech Temp. This gauge kit comes WITH the of how your engine operates in various conditions, which is important! A properly installed CHT gauge can help prevent this sort of catastrophe and prolong the life of your engine. $79.25. . It's the only one in this price range that provides accurate digital readouts (in fact it's the only accurate gauge in this price range, including traditional analog models like VDO). The Minari and Air Conception have a horizontal engine so the extension is not needed. Once again, red . It is still UNCERTAIN, but we may re-open a substantially downsized version of our store again in the Spring of 2023. This leans out the fuel mixture and this is why you increase jetting at lower temps. . The Cylinder Head Temperature Gauge measures the temperature of the cylinder head of an engine, commonly those that are air-cooled. EGT is affected by mixture. JPI. If all you have is the factory CHT gauge, then all you know is the CHT of one cylinder (and only very approximately at that) you have no idea how hot the other five are running. Also had a mechanical oil pressure gauge on the engine, had to open the engine cover to check but dash light was functional (off at . The final approval tests went exactly as planned and we are thrilled to further extend our range of gauges for classic cars and motorcycles.". Ambient air about 70-75 deg.F Front to rear variation is only about 5 deg. 12v connection. Bottom line: a cool running engine will last longer and have fewer problems. 1. The Evans VP-1 and VP-2 Volksplane plans (which assume a hand-propped engine) call for just a tachometer, oil pressure, and oil temperature gauges. Consequently, peak EGT can be used to identify a stoichiometric mixture, and decreases in EGT from peak can be used to establish mixtures richer or leaner than stoichiometric (ROP and LOP). Immediate shipment of requested products is NOT guaranteed. I didnt turn that fan on. They readily available, inexpensive and pretty easy to install. for Spark Plug M14 919 085 113C available from stock. Always do a thorough test of the fuel delivery system before assuming there are ignition or While tightening the spark plug, hold the sensor so it does not touch any parts of the air duct (if there is one) or the cylinder at any point. Southwest - Chandler, AZ This engine had HST installed over both gauge wires which is the best way because there is less chance of the wires being snagged. Why you need a CHT gauge?. A water cooled engine usually operates with a coolant temperature of 180-220. d.) CHT sensor installation Remove the existing spark plug. All wiring must have some slack to allow for flexing of the side bar. If you can JUST hold it without it burning your fingers, the engine temperature is OK. Matt Cramer -1966 Dodge Dart slant six running on MS3X. We will not drive without one! The CHT wire, however, VDO 600F Cylinder Head Temperature (CHT) Gauge, Cockpit, Black Face, 2 1/16", V310901. Power Products. From the pilot's perspective, this involves learning the best practices for power control, leaning procedures, cooling, and other operational considerations. system does not use the expensive but durable "spaghetti wire" for the connection to the thermocouple. Most light aircraft engines are air cooled: air is drawn into the engine bay through inlets in the cowling and directed over the cylinders by a set of baffles. VAT Reg No GB 5582 14927 A different engine went over 260 degC with no issues. c.) Tachometer sensor wire location The RED tachometer sensor wire may be shortened as needed and loosely wound around the secondary (spark plug) wire 3 or 4 turns. It is also good to have an hour meter/tachometer so 0 of 0 people found the following review helpful: 1 of 2 people found the following review helpful. Fouled or malfunctioning spark plug or ignition wire:Elevated EGT on affected cylinder only (usually by about 50F or so). That is because the extra power produced by the Jaguar CDI (from not allowing any misfires due to weak spark) produces more heat. Home VW T1 Beetle Electrical Beetle Gauges & Senders CHT Gauge, Cylinder head temp 52mm S/Comp Including sender. the (24)" extension must be used for some paramotors. which varies widely from manufacturer to manufacturer. IMPORTANT GAUGE YOU CAN HAVE ON YOUR VW! Stow the extra wire lengths in loops just below the side bar attachment Leave the old CHT in and add the JPI. Originated by Hal Brown in 1972. A reamer works much better than a drill bit. EGT usually varies between normal and slightly elevated, often (but not always) in a rhythmic fashion with a frequency of roughly one or two cycles per minute. Highly accurate and durable thanks to AutoMeter's patented air core meter movement, a single wire, 1/8" NPT temperature sender is included. I'm used to always running TrailTech temp gauges on old 2 stroke mopeds. Of course, if pilots have lots of money and like ignorance, who would care? fuel inlet filter and a worn out fuel pump. The gauges are This website uses 'cookies' to give you the best, most relevant experience. Retarding the ignition timing so that the spark plug fires later causes ppto occur later and decreases CHT. One purpose of the dual ignition system on an aircraft . e.) Spark plug reinstallation Put the CHT sensor on the spark plug and then the spacer washer, if there is one. . Failure of one spark plug or magneto can also affect CHT, because the air-fuel mixture takes longer to burn when it is ignited by only one spark plug instead of two. I'd consider but I prefer analog. This probe is not compatible with the thermocouple probes required (for the EDM)". 650 air-cooled, dual carb, dual ignition, rebuilt (like new! The engine is simply not capable of producing EGTs that are high enough to harm anything. by Robert Hodge Fri Feb 20, 2009 12:10 am, Return to General, New users, Purchasing, Powered by phpBB Forum Software phpBB Limited, A general forum and a place for initial or prospective users. These engines were highly stressed and it did not take much of a change to melt a piston or worse. Midwest - West Chicago, IL Having anything Of course, if pilots have lots of money and The They simply indicate that a lot of energy from the fuel is being wasted out the exhaust pipe rather than being extracted in the form of mechanical energy sent to the propeller. catdoo. With simple installation and its slick clean look, it makes it be another must have Ural Accessory. I appreciate your viewpoint but really I think you need to have a temperature gauge on your engine to really know what is going on with it. A cylinder head temperature gauge (CHT) is an essential tool used to monitor the running temperature and health of any air-cooled engine. I very seldom refer to EGT when I lean my engines; I use fuel flow to get somewhere in the ballpark, and then fine-tune by reference to CHT. the trick is the cool down. One caveat: Turbocharged engines usually have a turbine inlet temperature (TIT) red line that should be observed, particularly when flying at Flight Level altitudes. float-type carburetor which is easy to adjust in the midrange, unlike diaphragm carburetors, and going lean in the midrange is very easy wheres the evidence to say that that bicycle caught on fire due to excess head temperature? An unmodified Top 80, for example, will have a cruising temperature between 120C - 170C with the TTO CHT gauge, depending on ambient Swansea ), 4.5mm (3/16") wide black nylon zip ties From a powerplant management perspective, its crucial to understand that CHT and EGT tell us quite different things about whats going on inside the engine. should never be pulled tight at any point. Checked and adjusted valves about 10k km ago. EGT is a true example of what is actually going on in the combustion of the cylinder. Sender installs over the engine spark plug, typically on cylinder #3. This is because un-vaporized fuel in less than 70C will have problems with fuel vaporization which is necessary for efficient combustion. CHTs above 400F should be considered abusive, and grounds for doing something right now to bring them down. Please do NOT rely on PHOTOS while shopping as many of our products have selectable product options that may change the nature of the product being ordered compared to the representative photo. Alternatively, changing the mixture can affect CHT by changing the rate at which the air-fuel charge burns, and therefore causing ppto occur earlier or later. Support and discussion forum for Megasquirt 1, 2, 3, Microsquirt/module, DIYPNP, MSPNP2, MS3-Pro, Quick links: Manuals : Megasquirt info On a air cooled engine, all you can do it postpone blown head gaskets. separately unless you want to have spares! Be very careful not to twist the sensor/wire assembly when tightening the spark plug. or broken fan belt), Oil Pressure. The location shown here is the best and will result in the least wear and tear on the sensor wires. cylinder head (which is not always possible on some engines). You should establish a target CHT that represents the maximum stress you want to place on your engine - 380F works well for most Bonanzas and Barons under typical conditions - and then adjust your power settings, mixture, and (if applicable) cowl flaps to ensure that all cylinders are operating at or below that target. So you can figure that fin temperatures are at least 100 degreees below the temp of the average head temperature. The CHT can be setup with either Fahrenheit or centigrade. a bag tie, as here, but this is not necessary. We rely heavily on email as the most efficient and accurate way to serve our customers. by Bleyseng Thu May 19, 2011 6:32 am, Post It is quite common for different cylinders of the same engine to indicate quite different EGTs, and thats perfectly normal. A We feel critical temperatures are 425F when the thermocouple is mounted under a 14mm spark plug. Less fuel, more air creates a lean condition and be severe Some aftermarket temperature sensors and overheat warning systems have become available over the years. plug and the sensor. (assuming it was installed under the #3 plug, so you can compare it to others with the same install location). at hardware stores), 3/8" or 1/2" heat shrinkable tubing (HST), #14 drill (11/64" or 4.5mm) or reamer to widen the mounting holes in the gauges. Leaner mixtures cause EGT to decrease simply because less fuel produces less energy. This gauge kit comes WITH the wiring harness, and the sending unit, you do not have to purchase these separately unless you want to have spares! The head temperature gauge, which is commonly found on air-cooled engines, displays the work that the engine is doing more quickly than an oil or water temperature gauge. 230C = 450F which is the maximum heat you want on extended runs. Please trust that even when we can't reply to your email promptly, we are continuing to work to fulfill your Order Request as best we can, and we will contact you at any point where we have any new information that is not already posted in your online Order Progress/History area in your customer account. cannot lubricate engine parts. Reason I'm asking this is because this engine has CHOKED / tapered cylinders up towards the combustion chamber. You should establish a target CHT that represents the maximum stress you want to place on your engine 380F works well for most Bonanzas and Barons under typical conditions and then adjust your power settings, mixture, and (if applicable) cowl flaps to ensure that all cylinders are operating at or below that target. CHT-WS-KK series CHT Sensor Specifications: Type K thermocouple Special Limits of Error (+/- 0.4% of reading) -40 F to 500 F operating range (-40 C to 260 C) Stainless steel over-braid cable with FEP insulated conductors, 6 feet or 12 feet Response time constant (1500 milliseconds) Bendable ring terminal. Synthetic oils burn at higher temperatures than all others but they You might wonder why more probes and gauges aren't required. A drill press and reamer was used to PRODUCT AVAILABILITY can vary and short-term backorders are common. Advanced ignition timing that ignites the air-fuel charge earlier and causes ppto occur earlier decreases EGT. FAA. than normal running engine is fouling of the piston rings and lands. Typical installation on the left side bar of an Air Conception. Typically, there is a sensor mounted in the exhaust of each cylinder of the engine which allows us to watch each cylinder temperature individually so we can compensate jetting to balance out heat conditions to produce . CoC. Cylinder Head Temperature GaugeGaugeNew Product, Categories: We provide the classic VW hobby with tech tips, project advice, and quality parts for VW Restoration, VW Performance and Custom Aircooled VW projects. The CHT gauge kits consist of a sensor and the gauge itself. Additionally, paramotor engines are designed mechanically to run at a specified temperature them and could guess when maintenance is due, but then. Why not have an exhaust temperature gauge (EGT), as do general aviation (GA) aircraft? The purpose of the TIT limit is to protect the fast-spinning turbine wheel from blade stretch. mounting points. The CHT-100 is an advanced Cylinder Head Temperature Sensor for the Corvair Spyder and Corsa models. CHTs are pretty expensive, I was pricing them yesterday. The CHT gauge kits consist of a sensor and the gauge itself. I'll have to keep relying on common sense.. somewhat off topic, but when you were running this, what sort of numbers were you seeing? However, its not essential to use EGT for leaning unless youre particularly curious about what air-fuel ratio you are using. And we will continue responding to emails through until early March 2023 because we are wholly committed to resolving any other issues that may arise from previous sales. You do NOT want debris falling into the cylinder. *** Supply-chain disruptions have hampered our ability to acquire/restock items reliably, and a lack of backorder ETA information is the frustrating "new normal" for our hobby. There are two Thermocouple lengths - 4.5m and 6.6m - with cables suitable for 12mm and 14mm Sparkplug fixings. VDO 600F Cylinder Head Temperature (CHT) Gauge, Cockpit, Black Face, 2 EGT measures heat energy wasted during the exhaust stroke, when the cylinder is under relatively low stress. I am still astounded that this vitally important gauge is not standard issue for all paramotors. Slightly reduced CHT on all cylinders. If pilots want to spend the money and time to install an EGT, do it but I do not think it is VDO 600F Cylinder Head Temperature (CHT) Gauge, Cockpit, Black Face, 2 1/16", V310901 is used to monitor the critical Cylinder Head Temperature on the Aircooled VW Engine. In the case of airplanes which do not have cowl flaps, an indicator shall be provided if compliance with the provisions of 3.581 is by hambone Sun Apr 03, 2011 7:08 pm, Post Install an Oil Temperature . Join Date: Jan 2011. air cooled aircraft engines go up to a minimum of something in the 425F range which is about 218C. That's more concerning and being hopefully handled by a small oil cooler and a switch from 0W-40 to 20W-50 Mobil 1. Mount the gauges Use nylon zip ties to mount the gauges on the left side bar. Learn more An exhaust gas temperature gauge ( EGT gauge or EGT sensor) is a meter used to monitor the exhaust gas temperature of an internal combustion engine in conjunction with a thermocouple -type pyrometer. What's a safe maximum temp on a force/fan air cooled small 125cc/232cc all aluminum engine? Engines cooled by air rather than water require a steady and constant flow of air and accurate temperature monitoring is critical as overheating can cause engine failure. "Our design team worked closely with an important German customers. Complete installation instuction included in gauge kit. VDO 600F Cylinder Head Temperature (CHT) Gauge, Cockpit, Black Face, 2 1/16", V310901 is used to monitor the critical Cylinder Head Temperature on the Aircooled VW Engine. A Cylinder Head Temperature gauge is the missing gauge on any air-cooled vehicle. We are now only fulfilling order requests only for items that we have in stock OR that we know can be acquired within a defined timeframe. Have you ever checked n adjusted the valves, check the compression also . Prevent damage to your engine and ensure maximum performance and reliability with this AutoMeter Electronic Cylinder Head Temperature Gauge. engine running temperature very quickly whereas a CHT can take 20 seconds to register a change. VDO 250-1650F Pyrometer Temperature (EGT - Exhaust Gas Temperature) Gauge, Cockpit, Black Face, 2 1/16", V310953. You will get an idea Failure of one spark plug or magneto causes the air-fuel charge to take longer to burn, so it causes ppto occur later and EGT to increase. Recall that during the Otto cycle power stroke, peak internal cylinder pressure and temperature optimally occur at 15 to 20 of crankshaft rotation after top dead center a point denoted by pp. That's a good price. Secondly, an EGT costs wiring harness, and the sending unit, you do not have to purchase these As the 3.0 litre SC engine we have is proving troublesome and needs a rebuild it seems like a good idea to try to convert the CIS to an EFI and I have been looking at various options. Sensor id Ring Size 14mm. Manufacturer; Certification; Size; Alcor. In most cases we are able to honor advertised price, but in the RARE case a substantial price increase occurs, you would be notified and given the option to cancel. because this type of tape quickly smears black goo after it has sat a while. EGT is also affected by ignition performance. While a CHT gauge can also give an indication of mixture strength, it will be slower to react than an EGT gauge because the heat must travel through the mass of the cylinder head. it should not extend beyond the rear of the side bar. Sounds like it's running lean. cooler is better. Commonly used on air-cooled engines, the head temperature gauge displays the work that the engine is performing more quickly than an oil or water temperature gauge. Please only contact us by PHONE and leave a voicemail if you have been unable to reach us via email for some reason, OR if your situation (or tech question) is impossible to convey in writing. Recently installed some CHT gauges on some fan cooled sleds. Replace the old CHT with an STC'd item and write it up on a 337. the form of droplets will not burn in the cylinder and just pass through. It may not display this or other websites correctly. also easily visible on the side bar. The CHT wire is delicate and unfortunately they only read up to 125deg, but somethign similar would be ideal Engine Guard - Product Overview - Engine Guard basically this.. "cylinder head temp gauge" VDO 12v DIGITAL CYLINDER HEAD TEMP GAUGE KIT 4WD TRUCK | eBay EUR. Swift Gauge Dual 2 Inch Round Cylinder Head Temperature 100-7000F | Aircraft Spruce THE AVIATION SUPERSTORE FOR ALL YOUR AIRCRAFT & PILOT NEEDS | 877-4-SPRUCE Home / Instruments / CHT Gauges / Falcon & Swift / Swift Gauge Dual 2 Inch Round Cylinder Head Temperature 100-7000F Swift Gauge Dual 2 Inch Round Cylinder Head Temperature 100-7000F VDO Cylinder Head Temperature (CHT) 14mm Sending Unit, V323701 is used to monitor the critical Cylinder Head Temperature on the Aircooled VW Engine. **UPDATE*** WE ARE NO LONGER KEEPING LONG TERM BACKORDERS OPEN FOR LATER FULFILLMENT!! Important: The absolute value of EGT is not important. and fully adopt the metric. I have tried many locations. more). Usually you want temps in the 300-400F range. 2023 Caerbont Automotive Instruments Ltd, Classic SMITHS Speedometers, Tachometers and other gauges, New SMITHS International Dual Needle Boost Gauge. Exhaust temperatures would be less than 600F. . Fast Response time: 500 msec. Note: the stock wire on the CHT is short so around 400F, and we can't say this is wrong. Run whatever oil you like, but I'd run SAE 30 and check intake / cooling fins regularly I thought about putting exhaust wrap on it this morning. Please check the boxes for the options that you would like to add. Owner's manuals from smart Italian manufacturers always remind pilots to *NEVER* go to full throttle until the engine warms up (70C or Peak EGT occurs at approximately the stoichiometric (chemically correct) mixture of 14.7 pounds of air for each pound of fuel, at which there is exactly the right amount of oxygen to oxidize all the hydrocarbon chains in the fuel. the thermocouple is mounted under a spark plug. by Matt Cramer Mon Feb 16, 2009 10:43 am, Post The gauge measures in Celsius up to 1300c or 2372 Fahrenheit Easy installation. The Cylinder Head Temperature Gauge measures the temperature of the cylinder head of an engine, commonly those that are air-cooled. A Cylinder Head Temperature gauge (CHT) measures the cylinder head temperature of an engine. failure of the side bar while flying could be catastrophic. What are factors contributing to a higher head temperature? The method used to mount the gauges are the same on any Miniplane frame. Note: If you must install an oil pressure gauge use GB 264-1/8 tee fitting and GB 265-1/8 pipe nipple to install the factory (Bosch VWA021-919-081B) light sending unit and the gauge . Aircraft engines can provide thousands of hours of reliable service, provided that they are maintained and operated properly. wire with too many turns it will overload the circuitry in the gauge and the gauge may give erratic data. These gauges are best As the ambient temperature increases, the reading on the gauge decreases; i.e. Currently our response time to emails is slow (we are severely short-staffed). If LOP mixture, reduced EGT and CHT on affected cylinder, and possible engine roughness. There is just enough room between the fins for the sensor to fit. Gauge importance (to US), in order, Cylinder Whats important is the relative value of EGT for a particular cylinder compared to that cylinders peak EGT value. by Robert Hodge Sun Feb 15, 2009 6:58 pm, Post EORI Number GB558214927000. This is THE MOST IMPORTANT GAUGE YOU CAN HAVE ON YOUR VW! The burn rate of the air-fuel charge is fastest a mixture that is slightly richer than stoichiometric, approximately 50F rich of peak EGT (50F ROP). Also note the charred and failed Air Cooled Engines. Also, at higher elevations, you . and melted causing the ring to become loose (3rd photo). Some of the bigger engines can safely run at 250C (482F). f: 01639 732201 Panel Cut: 76.5mm x 39.2mm. This is THE MOST The three most popular gauges, cylinder head temperature (CHT), oil temperature (OT) and oil pressure (OP), all have accuracy issues but they are useful for trending and preventing meltdown. For this reason, engine exhaust temperature If the temperature increases very quickly, the crown of the piston can melt at the center and form a hole. GA aircraft that are carbureted Comes with box and instructions. Depending on the engine, the cooling air duct may have to be modified in order for the CHT sensor to be mounted underneath the spark plug. Pilots who are concerned about this can buy synthetic oils that are not "racing" grade but they cost a lot more. Smaller ties could be used but they are likely to break which is why the 4.5mm ties should be used.