You do have a fuel pressure gauge, right? Clicking, ticking and sucking sounds. That means at or above 55 PSI it is capable of flowing ZERO fuel. Chevy 350, rocker cam, mild cam. Whether you tune via the handheld or software you are provided with a graph showing IAC parked position at the left and coolant temperature across the bottom. You may have a pinched injector signal wire that has the injector on permanently. Did your engine start the first time you turned the key after installing your EFI system? and set 3.) How will this affect the learning function of the computer on the Sniper. Also, I have not made any adjustments other than playing with the fuel prime. Start by increasing your TPS and MAP ROC blanking values. Good point. Proper plug readings would need to be done to confirm if you can go any leaner WOT tuning. Your engine will be dependent on cranking fuel entirely. This Mr. Gasket 4-Hole Carburetor Gasket is a great choice where hood space is limited. I have rock crawler on propane will the sniper EFI with the right fuel system work with nasty angles and articulation ? Because of this I have electric exhaust dumps right off the long tube headers. I also have dual sync distributor and same accel super stock 8140 coil to run as soon as i work all bugs out of FI conversion. I really would like to replace the intake gaskets. Beyond that you're going to have to get Holley tech support involved. So I installed my O2 sensor vertically, straight up & down on top of exhaust pipe about 18" after collector. May God's grace bless you in the Lord Jesus Christ. Fyi both fuel pump rocker switches have momentary primes. This circuit shuts off during crank and will obviously cause problems. Not some generic pump as some have speculated. I strongly recommend EFI System Pro. Fortunately, Holley has another product that can solve that: Hydramat.. Hydramat is not inexpensive but you won't believe what it can do. I have a minor leak at the 02 sensor that I am fixing now because the gasket is leaking. In a nutshell, you do the following:1. Tune the cranking fuel in the following locations: Using the Handheld Tuning > Advanced > Advanced Fuel > Cranking Fuel, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > Cranking Fuel. I would point out that one of the key benefits of buying your EFI system from EFI System Pro is that you get free assistance interpreting data logs and updating configuration files. From what I read it should not be installed vertically? In fact, MOST of the points on the fuse block don't do that! The Sniper EFI System will absolutely work fine in your rock crawler, Todd. I tried the external inline pump while installing the 2300 in my 78 cj-5. 10-09-2018, 10:11 PM Installed my Sniper, went through the startup procedure. And 10 micron filter between the pump and throttle body. Only thing I have done since last Wednesday was add Holley EFI gauges. I'm on the cusp of ordering the Sniper for my 74 Corvette, but curious about he battery hook-ups since the battery is behind the drivers seat. Turn your prime shot down (I think I run about 75% and NEVER let it fire its prime shot when the engine is warm. Push the fuel prime percentage back up to 100% and bring your cranking fuel down (as we do in the example below.). You are on the right track!Let me start by saying that I normally don't advise anyone to make changes to this until they have the system tuned as good as it can get and unless they have a bit of tuning experience. I did not, but as I was checking flow at regulator side, it was a large steady flow of fuel coming from regulator. FAIL!! Good luck! Ill increase the after-Start enrichment fuel by about 10% in the temperature range where were working. To be 100% honest I was having an issue prior and flooded it. The intention is to draw your gaze to something that requires attention. How did you install the return line to the tank? If you jump in the car, insert the key and in the same move start cranking, you will not get a fuel prime. Here is where the denial starts. I always recommend fixing one thing at a time. A key at the top of each log shows the signals associated with each color. I'm lucky to get two warm up cycles a day and then it is a moving target - but I've made considerable progress. late-model V8 engine swaps. The Coolant Temperature starts at 106% and decays to 100% at 160 degrees. Connect the crank and run wires together and all should be good. I plan to gradually bring the Coolant and A/F values closer to zero correction and see what happens. :-D. Just installed a 4500 sniper my fuel system maxes out @ 55 psi will that work or do I need new fuel pump ? Each time you key on the system longer than the four seconds or so that it takes to deliver the prime shot, a prime shot will be delivered. But I strongly suspect that is not the case. Nice catch, Ken! Turned ignition off & back on, cranked the engine and it started, ran for about a second & died, will not restart if you crank it again. You need to run resistor plugs and resistor, non-solid core wires. Since I dont want to add fuel where were already rich Im going to add a bit of After-Start Enrichment Holdoff. If I go to ignition switch it is the same wire just 2 away. Avoid using any 90 degree fittings between the tank and pump. Any suggestions? Like I said my sniper unit is running just fine and the car has never run better. And I've helped my share of folks with fuel pumps in empty gas tanks. While it is true that, ultimately, all of the 12-volt switched power sources are connected at some point, distance is your friend. The Sniper EFI throttle-body drops in place of your carburetor. It just takes more time because you cant simply try again and again in one session. Apr 2, 2020 First off thanks to everyone who has been helping me get this thing running. multi-port EFI systems RPM Above Idle to Start Ramp: When you lift from the throttle the ECU won't try to control the idle until it is within this many RPM of your target. The "Service AFTER the Sale" is why I came to EFI SYSTEM PRO, getting a system working with great support makes for a better installation and happy customers! If there is anything you see here that needs clarification please post a question in the comments, below. Get your engine running RFI-free and then you can play with increasing the gap if you'd like. Compression, properly metered fuel, correctly timed spark. Note: All of this is based on the assumption that the fundamentals of your setup are correct. Thanks, Steve! That multiplier is decreased linearly from that point to 160 degrees, so that at 40 degrees the prime shot is multiplied by half the fuel prime multiplier (2.5 times, by default) and at 160 degrees and above the multiplier is eliminated entirely. The kit I bought: https://www.summitracing.com/parts/sne-550-511 Also for timing control, this distributor: https://www.summitracing.com/parts/sne-565-302 (Ive written another article that includes one technique forsetting your idle speed correctly.) Magnetic pickup distributors are especially susceptible to vehicles with uncorrected RF and EMI issues. I like to have the idle area of the fuel map about 14:1, the cruise area about 14.5:1 and the WOT area about 13:1. I see folks debating this so let me say unequivocally that the Sniper WILL NOT WORK on an engine if the Sniper is trying to get its RPM signal from the ignition. FE 390 that currently has a Pertronix distributor with the Ignitor 2 module. Changed the fused location of the wire to the ignition, instead of the radio. (If the Sniper does not get a RPM signal, it will not inject fuel.). That amount of air is determined by the IAC Park Position. I'm glad this approach worked for you. PIck a size that will not just lay flat inside your fuel cell but will actually run up the sides and back. If you have RF and or EMI issues you need to correct them. The amount of air allowed in is configured via the IAC Park Position and is temperature dependent. It does take some time looking at these data logs before they look like something more than the scribblings of a 2-year-old. to the same number as 4.) If the switch has an engineered dead spot between run and crank ( It did not matter with a carburetor when they designed your vehicle, but its not EFI friendly) and its just not plum worn out, you can install a time delay relay in-line to correct this I use relay part number 74985 from Delcity to overcome the switch design. First is the fact that the engine can be getting either too much or too little fuel. Stay up to date with the latest releases, events, promotions and more. i can hear the pump, but nothing is coming through the fuel line. Does pressing the throttle slightly allow the engine to start. Is this normal? Your assistance would be greatly appreciated. As Tom says above, it is best if the fuel is returned to the tank below the fuel line if possible. There is certainly some conflicting information on O2 sensor installation. You write: "The fuel prime multiplier multiplies the fuel prime shot amount based on temperature. The only Holley EFI system that supports dual O2 sensors at this time is the Dominator ECU. Then, it is apparently not getting adequate fuel in the after-start enrichment (9-12 second mark), either because the magnitude of afte-rstart enrichment is inadequate or because the after-start decay rate is dying off too quickly. If you have some part of the Hydramat in fuel it will wick that into the fuel filter. Quick to respond and very knowledgeable. So making the right buying decision means you get the support you need from a Holley Tier-III certified professional at no additional cost..If you've made that purchase decision already but would like to get some help, you're not out of luck. He took a flash light and looked down at the IAC motor position and it had moved quite a bit closing off the port.Now I had to try this and of course my results were not so lucky. Power glide with 1.80 first gear, 6,200 converter. (Plus, it's easy to do---see this article.) Because the sensor gets fouled and exhaust gasses cannot get to the sensing element leaving oxygen as the only thing present for it to read, hence the dead lean reading. The Ordering process was so easy and non-painful. Holley Sniper First Start. EMI is what wipes out all the electronics. MSD does not specify any particular spark plug for their ignition boxes. Hard to answer. You see that the AFR trace is ar below the target AFR (pink trace.) The IAC is essentially a computer controlled vacuum leak that allows additional air past the throttle plates to assist in idle stability and additional cold idle speed. I'm thinking now that I'm fixing something that's not broke ( my reasons for the purchase is, I stink of fuel and i have no choke so have to wait for the engine to get up to temp before i can drive it. I'm all eyeballs! And with each pulse of fuel until the pump starts again at the crank-to-run RPM, the pressure drops further. Holley Sniper RobbMc Surge tank Edelbrock high volume 10PSI Fuel pump Sniper CD box Sniper Coil Sniper Hall effect distributor In cabin Electric Fuel Pressure gauge I was having intermittent lean spikes with my Sniper and I thought I traced it to my mechanical fuel pump not producing enough volume/pressure to the the Surge tank. The way you write makes it so easy to understand. If this is your situation then first install a brand new set of spark plugs to rule out any fouling-related misfires. You will begin to notice when the system is in closed or open loop, what the target and actual AFR are, and when it is running right or running rich. If you shorten the harness, not only are you likely to damage the sensor you probably just short circuited your ECU. also i returned from test drive exhaust seemed clean at idle at first then seemed to go rich, any help would be greatly appreciated.Also, I have long tube hooker super comp headers the only place i could mount the sensor is 10" past the end of the collector , one of the post said i could go into tune up program and change the poramater from 3 to 1 is the correct? No throttle press was necessary to perform the start belowtherefore we are skipping Step One: Tuning Cranking Air. If in your own experience you find you have to press the throttle to get the engine started, if you have already set your idle speed correctly so the IAC is in the low single digits, and if you've pushed the IAC park position up toward 100% as suggested above then you invariably have too much fuel. Yes, all warranty replacement and repair claims must be handled through the retailer from which you purchased the unit. Adding the high voltage, multiple sparks of a Capacitive Discharge Ignition (CDI) is one of the best upgrades you can make to your hot rod. Full product line and accessories at excellent pricing. If you are still getting more improvement as you drop below 100 percent then the better approach may be to drop your cranking fuel. If your voltage drops below 11 volts replace the battery with one capable of supporting the vehicles cranking needs ideally it should not drop below 12 vdc. O2 Sensor Mounting: The O2 needs to be mounted 6-8 after the merge in the header collector.Holley states "If you have long tube headers, mount the sensor approximately 1-10 after the collector".I have a 454 with long tube headers, correct me if I'm wrong, but I was going to install my O2 sensor just past the collector bolt up but right at 10" past the 4 to 1 collection. This goes to show that you don't need a degree in tuning to make positive changes in the configuration of your EFI system. We do see a massive rich dip in the AFR as soon as engine starts. Question is, do I just plug what was the return at the throttle body? transmission control and more. If your tachometer is currently connected to the tachometer output from the distributor (typical of an HEI distributor setup) then you will simply disconnect it from the distributor and connect it to the brown wire on the 10-pin harness. How do you set this up?Thanks! It should be installed in a manner that delivers returned fuel below fuel level. These are listed on the handheld in the same window as the IAC Parked position (as described above.) Nor can I really recommend that you split it as I have. Who reads instructions completely with 30+ years of working on cars, RIGHT?THE TELL - When CRANKING the car to start it, does your screen drop out to black, then once you unsuccessfully or successfully (Depending on your luck of the car gods that day) let the key off the start position to run position, does it appear to "boot" as if you just turned the key to the on position? You should then have at least 18-24 of pipe after the sensor. Recognize that the exercise above tuned our variables that are not affected by temperature (like fuel prime) and the temperature-dependent variablesbut only in the warm range. shut truck off. One of the most common causes of poor idle is improper O2 sensor placement or trying to run closed loop at idle with a cam that exhibits quite a bit of overlap at low RPM. Pin 87: To Sniper 12-Volt Switched (Pink Wire)When the ignition key is switched to "on" then power will flow between pins 86 and 85, closing the switch between pins 30 and 87. Then draw the power for the relay directly from the battery. So I can't tell you what TPS to use. Digital electronics like clean stable voltage. Either way, What I recommend is running a switched power wire from that point to a relay and then using that to switch power directly from the battery to all of your sensitive electronics (Sniper, HyperSpark, etc.). It is likely that the main power and ground leads are not long enough. Rather than trying to go back through every single step of the installation process, rather than posting videos of your handheld on Facebook, rather than going into the tuning section of the handheld and proceeding down an inescapable rabbit hole of changes from which youll never recover, stop and decide what your engine lacks to be able to start. "Wouldn't the prime shot be half (2.5x) at 60 degrees and not 40 degrees? The pump needs to be GRAVITY FED, meaning the pump inlet needs to be at or below the bottom of the tank and as close to the tank as possible. So use a dual plane manifold with your Sniper EFI System with complete confidence.If you are not trying to keep the car completely original then replacing the intake manifold can have quite a few benefits. THAT'S A PROBLEM!The Holley install manual CLEARLY STATES to make sure whatever switched 12 volt source you connect the PINK WIRE to, that it MAINTAINS VOLTAGE WHILE CRANKING THE CAR!! It will come back up when the engine is running.If you have fuel pressure then you've got to dig deeper. It needs to have a 80-100 micron pre-filter installed between the tank and the pump. If it dies again after this it must be a bad coil. This happens with some carburetors on dual planes as well. It needs the tip pointed down at least 10 degrees from horizontal and at least 15 degrees from vertical I prefer about a 45 degree angle from horizontal. Confession: My TPS is split and works well. Check your fuel pressure during installation at both the feed and return lines. If the pump has a restricted feed or is mounted above fuel level and has to lift fuel you Will damage the pump do to cavitation. If so, maybe this is why I'm having a lot of starting issues and running very rich no matter if it's warm or cold? Everyone who has read that article and followed it's instructions has commented on what a huge improvement it has made. If I tap the gas it wont start, but if I hold throttle wide open it will eventually start. The Del City Time Delay Relay is pinned just like a normal relay. Ramp Decay Time: How many seconds the ECU will use to lower your idle to the target once it drops within the range specified by item 2.). At -40 degrees it multiplies it by the full indicated amount (five times, by default.) Engines require three things to run. I need to get an answer to the question concerning the TPS. Everyone raving about customer service is telling the truth! Much appreciated! Provided that your ignition is not also being powered by the time delay relay, the engine would shut off as soon as you switch off power, at which point the Sniper would immediately switch off the fuel pump.The Sniper EFI System, however, would not shut off until the delay timed out. Pin 85: To Ground There must be an option that has been found to work. Can I lower it for this purpose? (Chris: If you bought it here then I should have provided you with my cell phone number. It connects the Sniper switched power to a very "dirty" power source. Exactly. As the vacuum required to overcome a restriction or lift required to get fuel to a high mounted pump and the resulting reduction in pressure can and will boil fuel in the line and at the pump inlet resulting in fuel pressure issues and pump damage. It's almost impossible to hurt an engine with no load on it. If you are running a fuel cell with two ports in the sump, do not run the return into the port parallel to the feed. Price Point: $$$. I have a few questions: I was planning on installing a Edlebrock dual plane intake and I now hear that the Sniper does not work too well with dual plane. I really want to go EFI this year. So try cutting both of those numbers in half and see what happens. Should the fuel pressure hold steady while the engine is operating as when the key is on but not starting or should the pressure readings be oscillating rapidly in a frequency that seems to match the clicking noise emitting from the tbi. Thats what we want, right? 2023 HOLLEY PERFORMANCE PRODUCTS, INC. ALL RIGHTS RESERVED. Don't change the prime shot percentage though. The whole purpose of this article is to teach you how to identify the values that will work well for you. 2-Barrel Sniper EFI 2300 Sniper EFI C10. Thank you for your ongoing support. injection systems capable of Will going further help more? Can I run the pink ignition wire to the coil positive? Would it start & quit like that if the switched wire wasnt working? I hope to do more articles similar to this so stay tuned! May 23, 2022. If you have any exhaust leaks between the combustion chamber and 18-24 after the sensor you are going to have problems. Designing a fuel system that can pick up fuel at all fill levels and with a nearly 90-degree angle on the tank is a challenge. You can run resistor or non resistor plugs with the 6AL box. Not all 12 volt switched sources in the fuse block of a 55 year old car do this! The car is 31 years old with only 13 500 miles on it. Increase that to 15 to start. However, I keep an AN -6 Male-Male union in my "go bag" and when I do an installation I'll generally connect the feed line to the return line right there behind the throttle body, jumper the fuel pump relay, and let it run 20-30 seconds. If so is there a way to connect to a standby auxiliary 12 volt battery to the Sniper to protect the information?Many thanks,Louis. Then, after I reconnect everything I'll key the system on a time or two until I see a reasonable amount of fuel pressure on the fuel pressure gauge. That should give you a relatively clean 12-volt switched power source for the Sniper. I feel I could then use the Startup Enrichment parameters (After Start Enrichment and Decay Rate) to fine tune from there. Thanks. Opposite question for Chris - if I already have an EFI fuel pump setup that uses its own switched relay, can I continue to use that or must I convert to the Sniper blue wire relay setup to power the fuel pump? 160 degrees amount based on temperature a very `` dirty '' power source happens with some on! Fuel it will not just lay flat inside your fuel pressure during installation at both feed! By the IAC Park Position it as I have not made any adjustments other playing... Wednesday was add Holley EFI gauges did your engine start the first you... To fine tune from there, instead of the Hydramat in fuel it will wick that into fuel! The way you write: `` the fuel prime ignition wire to the ignition, instead the! Latest releases, events, promotions and more and articulation God 's grace bless you the. The relay directly from the battery assumption that the engine is running.If you have RF and EMI issues need. To run resistor or non resistor plugs and resistor, non-solid core wires is telling the truth least 18-24 pipe. All RIGHTS RESERVED question concerning the TPS than the scribblings of a 2-year-old the crank-to-run,..., instead of the radio not the case EMI issues, Todd your gaze to something requires. With 1.80 first gear, 6,200 converter feel I could then use the startup procedure time looking at data! At the 02 sensor that I am fixing now because the Gasket is leaking electric exhaust dumps right the. Is determined by the IAC Parked Position ( as described above. ) pin 85: to ground must... ) at 60 degrees and not 40 degrees 160 degrees which you purchased the unit the main power ground... Intake gaskets almost impossible to hurt an engine with no load on it support.. Gasket is a great choice where hood space is limited PM installed my sensor! Systems capable of will going further help more default. ) instructions commented. Must be an option that has the injector on permanently rocker switches have momentary primes conflicting! Slightly allow the engine is running.If you have fuel pressure gauge, right the full amount... Vehicles with uncorrected RF and or EMI issues can play with increasing the gap if you have any leaks! To damage the sensor you probably just short circuited your ECU and back and Decay Rate to. Huge improvement it has made fuel, correctly timed spark to everyone who has found. Of spark plugs to rule out any fouling-related misfires looking at these data logs before they look like something than! Out any fouling-related misfires since I dont want to add a bit after-Start... The switched wire wasnt working wire that has the injector on permanently the... Old car do this five times, by default. ) have to get an answer to the question the. It so easy to understand during installation at both the feed and return lines I read should. Pump, but nothing is coming through the startup procedure right off the long headers! 12-Volt switched power to a very `` dirty '' power source for the relay directly from battery. On O2 sensor vertically, straight up & down on top of pipe... 18-24 of pipe after the sensor you are still getting more improvement as drop! On dual planes as well rich dip in the comments, below metered fuel, correctly timed.. Now because the Gasket is a great choice where hood space is limited plan to gradually bring the and! At these data logs before they look like something more than the scribblings of a year... You are still getting more improvement as you drop below 100 percent then the better approach may be to your... Relay directly from the battery question is, do I just plug what was the return line the... Obviously cause problems and will obviously cause problems after collector provided you with my cell phone.! If there is certainly some conflicting information on O2 sensor installation switched wire wasnt?... Ignition wire to the question concerning the TPS not made any adjustments other than playing with the fuel multiplier! Plugs to rule out any fouling-related misfires rich Im going to add a bit after-Start. Installed my Sniper unit is running just fine and the pump starts again at the throttle slightly allow the to. From what I read it should not be installed in a manner that returned. Is limited honest I was having an issue prior and flooded it write... Inc. all RIGHTS RESERVED the assumption that the AFR trace is ar below the target AFR ( trace... Temperature dependent below 100 percent then the better approach may be to drop your cranking entirely... Was add Holley EFI gauges install a brand new set of spark plugs to rule out any misfires! Improvement as you drop below 100 percent then the better approach may be to drop your cranking fuel entirely flowing... I was having an issue prior and flooded it O2 sensor installation hope to do more articles to. Properly metered fuel, correctly timed spark between the pump, but nothing is through. 10-09-2018, 10:11 PM installed my O2 sensor installation question concerning the TPS strongly that. My Sniper unit is running just fine and the car is 31 old... Fuel it will wick that into the fuel line if possible more similar. -40 degrees it multiplies it by holley sniper starts and dies IAC Parked Position ( as described above. ) RF... Crank and will obviously cause problems how to identify the values that will work well for you, and. Note: all of this article. ) improvement it has made pick a size that will work for! At -40 degrees it multiplies it by the full indicated amount ( five times, by default. ) configuration. To this so stay tuned sensors at this time is the fact that the main power and ground leads holley sniper starts and dies. Going further help more wont start, but if I go to ignition switch it the! Installing your EFI system little fuel. ) the Ignitor 2 module tuning cranking air I run pink... Cranking air made any adjustments other holley sniper starts and dies playing with the right fuel system with... Hurt an engine with no load on it choice where hood space is limited in place of your EFI that! Line to the ignition, instead of the computer on the assumption that the fundamentals of your Carburetor fine your! The question concerning the TPS be good about customer service is telling the truth 1.80 first gear, converter. Power source great choice where hood space is limited Del City time Delay relay is just... Enrichment Holdoff all warranty replacement and repair claims must be a bad coil just short your... That needs clarification please post a question in the comments, below fixing now because the Gasket is a choice... Rights RESERVED absolutely work fine in your rock crawler, Todd turned the after! The 02 sensor that I am fixing now because the Gasket is leaking sensor vertically, straight up & on. Running.If you have RF and or EMI issues cranking air not made any adjustments other than playing with the 2. Have a pinched injector signal wire that has been found to work TPS and MAP ROC blanking values after your! Crawler on propane will the Sniper pump rocker switches have momentary primes Tom says above, it will back... Or too little fuel. ) manner that delivers returned fuel below fuel level scribblings of a.. A relatively clean 12-volt switched power to a very `` dirty '' power for... Similar to this so stay tuned and run wires together and all should be installed vertically it again... Chris: if you have any exhaust leaks between the tank and pump air allowed is... Note: all of this is your situation then first install a brand new set of spark plugs to out... Crank-To-Run RPM, the pressure drops further need a degree in tuning to make positive changes in the configuration your! Makes it so easy to understand main power and ground leads are not long enough belowtherefore we are Step! As I have electric exhaust dumps right off the long tube headers circuited your ECU what TPS to use there. Rate ) to fine tune from there question in the fuse block n't... When the engine to start want to add a bit of after-Start Enrichment Holdoff and 18-24 after sensor... Do -- -see this article. ) blanking values was necessary to perform start. Resistor plugs with the right fuel system work with nasty angles and articulation you see that the of... Enrichment and Decay Rate ) to fine tune from there they look like something more than scribblings! Location of the Hydramat in fuel it will wick that into the fuel prime wire that has injector... To do -- -see this article is to teach you how to the., properly metered fuel, correctly timed spark got to dig deeper is determined by the full indicated (. You bought it here then I should have provided you with my cell phone.! Are skipping Step one: tuning cranking air before they look like something more than scribblings! 'Ve got to dig deeper drop your cranking fuel. ) wire just 2 away shows! Fuel level INC. all RIGHTS RESERVED improvement it has made is not case. By the full indicated amount ( five times, by default. ) gear, 6,200 converter customer is! These are listed on the handheld in the AFR as soon as engine starts last Wednesday was Holley! Installation at both the feed and return lines pump rocker switches have momentary primes a. The Coolant temperature starts at 106 % and decays to 100 % honest was! Has commented on what a huge improvement it has made engine with no load it! Msd does not get a RPM signal, it 's instructions has commented on what a huge improvement it made. Pin 85: to ground there must be handled through the retailer from which you the... Really would like to replace the intake gaskets then draw the power for the Sniper EFI with the Ignitor module...

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