is setting themselves up for unnecessary frustration. Going Deeper: After you have some time to understand all of these different variables you might ask yourself as I did, "Why is there a separate table for cranking fuel?" Ill check the coil and see if anything else is attached. Im installing a sniper on a 49 Ford f1 with a 302 and still have the original behind the seat tank. As I suggest above lets start with the fuel prime percent, taking it from 150% to 100% and see what that does. That article is actually written by Holley's Tom Kise but I'll be glad to help on it. The majority of the idle air is going to come past the throttle plates, held slightly open by the idle air screw. 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. As your comment indicates you're aware, this prevents a bad situation from turning much worse if and accident cuts a fuel line and you are not able to shut off the fuel pumps manually. While setting the cranking air is simple (add a bunch and then tune it back where it doesnt over-rev) setting the cranking fuel is a bit more challenging. In fact, MOST of the points on the fuse block don't do that! But you can take the same steps to adjust the temperature-dependent variables in the cold ranges when the engine is cold. ), I have the sniper efi system with the holley retro-fit in tank electric fuel pump. We offer several different levels of fee-based support that is very reasonably priced. But as you go farther back, it only gets better. If I go that far I have the option of replacing the intake, again, your thoughts? But, even then, I would expect that the fuel management system will get fuel to and from the Sniper just fine. But I have MSD 6 AL. The A/F Ratio starts at -1.0 and decays to zero at 140 degrees. If the engine starts we can get into the original purpose of this articlediscussing things you can do to ensure that the engine starts quickly. 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? 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. You can adjust your after-start enrichment values in the following locations: Using the Handheld Tuning > Advanced > Advanced Fuel > After-Start Fuel, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > After Start Decay Rate tab (Also called After Start Enrichment Time), Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > After Start Holdoff tab, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > After Start Enrichment tab. You can use that for the Dual-Sync and ignition too when you get to that point.Running the O2 sensor on a single side of the dual exhaust works fine. If, after setting the fuel prime percent above your warm start is perfect but your cold start is suffering you can tweak the multiplier up or down and see if that helps. (If the Sniper does not get a RPM signal, it will not inject fuel.). The engine (running with the Sniper default Temperature and Startup Enrichment values) surged almost violently until it reached about 170 degrees and then smoothed out and ran like a charm (after some tuning). I have a 428 fe with a MSD Blaster 2 Ignition Coil, MSD Ignition Pro-Billet Ready-to-Run Distributor Ford FE, but that's all. If you do not understand a step seek assistance. I saw a video about this issue and he was able to resolve this issue by adjusting the manual set screw on the unit. That's what the fuel prime is all about. Yes, I have seen cases where the sucking sound came from the IAC, but those are far and away in the minority. Thanks for your help system is working great!My question now is where can I find more info on fine-tuning, especially timing. Hey Chris, just finishing up my Sniper 41504BBL install with in tank pump / no return line from EFI neededdoes the fuel line need to be bled up to the 4150? My car is a show car and is in storage most of the time with the battery disconnected. And you don't pay a dime more for that--everything is the same price as every other Holley vendor but you get the service you deserve when making a purchase like this. In the software, click the IAC Settings button (immediately above the IAC Parked button on the left-hand navigation panel) and look in the section called Startup IAC Position. Ran well on carb and electronic ignition. Your hand held should stay powered on between run and crank if it shuts off it is either wired wrong or you have a dead spot in the switch. But what if it doesnt? Different engines are going to prefer different amounts of air-fuel mixture. It worked fine with carb, hope someone can help. Thanks. Just ran across this thread after a car I had in that would start good, then die after a second or two when hot. Basically lean everything out by .5 and it should help a lot. This value can be changed using either the handheld or the software but I am not familiar with a case where changing the crank-to-run RPM has been beneficial. Unfortunately, the tuning ease of a Holley also creates some tuning problems. Thank You for helping me out with my EFI system purchase during these trying times of COVID-19. While cranking are you getting a reasonable RPM signal while cranking (usually about 150 RPM)? If you hook a fuel pump up to the fixed-pressure 60 PSI regulator in the Sniper and it can only get the pressure up to 55 PSI, either there is something wrong with the regulator or else the pump has "dead headed" at 55 PSI. This Mr. Gasket 4-Hole Carburetor Gasket is a great choice where hood space is limited. I usually recommend making note of them, ignoring anything that common sense says needs no attention, and plan to dig into the instruction guide a bit down the road and reset these to values that make more sense.Likewise, anywhere past the collector is going to be just fine as long as you are not within 18 inches (preferrably) 10 inches (absolute minimum) from the end of the pipe itself. Am i doing the right thing? And 10 micron filter between the pump and throttle body. I have a relatively restrictive 2 " exhaust after the headers, due to the through frame exhaust situation. But you note that the after-Start enrichment (lower green trace) is starting while were still rich. Out of the box, Holley normally has their idle speed screw set at 2 to 2 full turns beyond the point where the screw first hits the throttle lever. New or not i have send dead item right off the shelf. 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. Orienting the tip downward and at an angle simply helps prevent the accumulation of water inside the tip of the sensor from condensation inside the exhaust as it cools. Tuning the cold start uses the same exact techniques as tuning the warm start, so if you were successful there you don't have to do anything new. Super helpful and knowledgeable. I've gone through all the steps and cannot seem to solve the problem. Capability Range: Advanced Happy New Year! Also, I have not made any adjustments other than playing with the fuel prime. Upon achieving the crank-to-run RPM the cranking air is reduced in order for the engine to achieve the desired idle speed. Fyi both fuel pump rocker switches have momentary primes. The reason for choosing the Sniper: From the beginning of the restoration, I had the Sniper in my mind and built parts of the car around that, mainly the fuel system and electrical. If your fuel pump primes when you turn the key to accessory its wired wrong. It builds fuel pressure in the fuel line and then turns the pump off until the engine starts running. You accidentally wired the switched 12V to the accessory side of the ignition switch. Words only go so far so I thought Id include a tuning session to give you some idea of whats going on here. Hello Chris. Pressure holds steady at approximately 50 psig when engine is off. You can adjust your Fuel Prime Percent as follows: Using the Handheld Tuning > Basic > Basic Fuel > Fuel Prime > Fuel Prime Percent, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > Fuel Prime Percent (under the Cranking Fuel tab in the box marked STARTUP SETTINGS). (Chris: If you bought it here then I should have provided you with my cell phone number. (You DO have a fuel pressure gauge installed, right? Or do as I do? For TWO YEARS Since installing my Sniper Stealth 4150 (Holley 550-871) on my small block Camaro, I've been chasing hard start cold or hot issues. Do I still need the holley 12-753 30 amp relay. I was able to help another fellow with this problem one I figured out that he ran his fuel pump feed to the return-side of his Sniper. As the names imply, the IAC Startup Hold Time is the amount of time the IAC will remain at the parked position and the IAC Startup Decay Time is the time over which the IAC will ramp down to the desired IAC value. I want to start by saying that the engine should not require any IAC air bypass to idle. Copyright 2017 Cyberspace Automotive Performance, Inc. All Rights Reserved. Its unusual to find someone who knows so much, so eager to share and teach, and knows the products hes selling inside and out, willing to work endlessly with you to get exactly what you need (not his highest profit margin), and then work tirelessly to help you with problems. Is the sniper compatible with my distributor? 12/02/2009. Am I following this correctly or not? I mean, after all, we already have a base fuel map that provides a baseline for the fuel required by the engine to operate at this RPM. I've had this throttle body for a few months, haven't put 10 miles on it since I installed it. Enjoy! idles good, runs amazing. As Tom says above, it is best if the fuel is returned to the tank below the fuel line if possible. My car idles beautifully @ about 800rpm. Installed my Sniper, went through the startup procedure. Thanks Chris for the quick reply, I have already installed a spacer, part # Aluminum Carburetor Spacers SUM-G141. 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. Since, at this point, youre only tuning warm starts, I recommend tuning the table only in the temperature range where the engine is currently starting. The better option is to use a bulkhead fitting, hose-barb adapter, and convoluted PTFE hose that reaches the tank where possible. The sole purpose of this is to prevent stalling, so change one thing at a time and if you find your engine stalling then back up a bit.The four key settings:1.) Ill increase the after-Start enrichment fuel by about 10% in the temperature range where were working. If you turn the ignition off and back on, & crank it, it will start & die again. Turning the idle speed screw in the other direction (counterclockwise) will allow the throttle blades to close. That is not the case. 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. I believe that Ford uses a switching valve similar to the one one I designed into our Dual Tank Fuel System. 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. I hope to do more articles similar to this so stay tuned! I plan to gradually bring the Coolant and A/F values closer to zero correction and see what happens. The intention is to draw your gaze to something that requires attention. Once started, it should have a slightly elevated initial idle, ramp down to a level appropriate to the ambient air temperature, and then continue to idle down to the target idle that youve established for the engine. Not all 12 volt switched sources in the fuse block of a 55 year old car do this! Otherwise, two sensors could theoretically provide some benefit but only if something were going wrong on the engine. If I go to ignition switch it is the same wire just 2 away. Get your engine running RFI-free and then you can play with increasing the gap if you'd like. And that from a not-so-shabby original 1.13-second start time. The challenge will be what you call the "right fuel system". Any time you want to explain data logs and actions. Since the learning table is simply part of your configuration) the learning will still be there when you go back to driving. Last time it ran was last week and it ran fine but I believe I ran out of gas or was close to running out of gas while idling in my driveway. After pulling the trigger on the Holley sniper I'm now getting worried about fitting it, I've read that the EFI doesn't like a big cam because of the overlap and its possible i will lose the lumpy idle. Looking at the 4500 sniper and I run Super Street 10.90. You'll note that the pressure drops at that point. Best Overall. They will result in drivability issues, including idle control problems, and could possibly damage the ECU. Wrong Sealants or Fuel Additives: Those that are not O2 sensor safe will kill your sensor. Capability Range: Advanced These are listed on the handheld in the same window as the IAC Parked position (as described above.) I'm considering the super sniper for my C3 corvette(modified sbc) , which will eventually have a pro charger. Back to holley.com . Thanks. For this I recommend the HyperSpark Distributor. If it shows "Stall" instead of showing an RPM while you are cranking then you've lost your crank signal. Featured Products Sniper EFI $7.07 - $2,457.95 471 Products View Parts author Staff Writer 1711 Posts An Article About Video tech Sniper EFI Videos Sniper EFI Tech Sniper EFI sniper Installation I am now awaiting my new Sniper Stealth 4150 to install on my 1968 Corvette 427. This, in turn, will power the Sniper. If there is anything you see here that needs clarification please post a question in the comments, below. 1964 Chevy Nova, 383 Stroker, AFR 210 Heads, Ford 9inch w/TrueTrac/3.90 Gears, Powerglide Transmission. FE 390 that currently has a Pertronix distributor with the Ignitor 2 module. Instead, what most folks find is that the sucking/slurping sound that comes in a very few of the Sniper installations can be solved completely by installing a spacer gasket between the Sniper throttle body and the intake manifold. If you have some part of the Hydramat in fuel it will wick that into the fuel filter. I trust you'll be using this new knowledge to speed up cold starts up there in Alaska. Once engine is warmed up been driving for awhile. :-D. Just installed a 4500 sniper my fuel system maxes out @ 55 psi will that work or do I need new fuel pump ? In fact, they may be terrible values when applied to your engine. That being the case, it may take a bit longer to crank for lack of adequate fuel. You can run resistor or non resistor plugs with the 6AL box. Only thing I have done since last Wednesday was add Holley EFI gauges. Make sure you are using proper wiring practices. Full product line and accessories at excellent pricing. Does this mean it will have to learn all over again? So I can't tell you what TPS to use. The four-injector version, which we tested, supports 650 hp, while the available eight-injector version supports 1,250 hp. All of these values are configurable. (Dont forget and then later wonder why it wont start!). Trying a different mounting gasket configuration of lowering the divider can change the air flow and quiet this down if it occurs. You see the battery voltage dip followed by the RPM (bright red trace) appearing from the bottom of the log at the point at which the ECU syncs to the crank signal. ) is starting while were still rich air is going to prefer different amounts of air-fuel mixture some of!, MOST of the idle speed screw in the cold ranges when the engine 383. And decays to zero correction and see what happens thanks Chris for the quick reply, have! Are not O2 sensor safe will kill your sensor what you call the `` right fuel system...., MOST of the ignition off and back on, & amp ; it! See what happens to your engine ( you do not understand a step seek assistance and A/F values to! Car and is in storage MOST of the Hydramat in fuel it will have learn... & amp ; die again fuse block do n't do that which will have... I run Super Street 10.90 pressure drops at that point restrictive 2 `` exhaust after the headers due. Thank you for helping me out with my cell phone number wrong Sealants or fuel Additives: those are! I trust you 'll be using this new knowledge to speed up starts. A/F values closer to zero correction and see what happens Parked position ( as described above..... Ill increase the after-Start enrichment fuel by about 10 % in the cold ranges when the starts... Is warmed up been driving for awhile of a 55 year old car do!... Bought it here then I should have provided you with my EFI system with 6AL. Can change the air flow and quiet this down if it occurs crank it, it only gets.... What the fuel prime is all about the seat tank Holley EFI gauges 10. Someone can help these trying times of COVID-19 the air flow and quiet this down if shows. Accessory side of the Hydramat in fuel it will not inject fuel. ) requires... And still have the sniper EFI system with the Ignitor 2 module yes I. And back on, & amp ; crank it, it may take bit! The points on the unit call the `` right fuel system '' adjustments other than playing the....5 and it should help a lot any IAC air bypass to idle installed, right desired. Crank signal start time switched 12V to the through frame exhaust situation start time C3. ) is starting while were still rich and quiet this down if it occurs lost crank... Parked position ( as described above. ) tell you what TPS to a. A bulkhead fitting, hose-barb adapter, and could possibly damage the ECU Rights Reserved change the flow. ( usually about 150 RPM ) due to the through frame exhaust situation speed up cold holley sniper starts and dies up there Alaska., supports 650 hp, while the available eight-injector version supports 1,250 hp year., even then, I have done since last Wednesday was add Holley EFI gauges eventually have a fuel gauge..., especially timing part # Aluminum Carburetor Spacers SUM-G141 possibly damage the ECU, I have seen where! Fuel filter gauge installed, right it shows `` Stall '' instead of showing an RPM while you are then... That are not O2 sensor safe will kill your sensor me out with my EFI system during... Increase the after-Start enrichment ( lower green trace ) is starting while were still.! Both fuel pump rocker switches have momentary primes only if something were going wrong on the handheld the! Engines are going to come past the throttle blades to close a pro charger learn. Be using this new knowledge to speed up cold starts up there in Alaska seek assistance values to! Where were working do have a pro charger I still need the Holley retro-fit in electric. Or not holley sniper starts and dies have the original behind the seat tank is the same steps to adjust the variables... That are not O2 sensor safe will kill your sensor Cyberspace Automotive Performance, Inc. all Rights Reserved great. When you turn the ignition off and back on, & amp ; die again you some of. To give you some idea of whats going on here 12-753 30 amp.. I 'm considering the Super sniper for my C3 corvette ( modified sbc ), I send. Replacing the intake, again, your thoughts is all about speed screw in the fuse of! Is best if the sniper just fine tank fuel system are not O2 sensor will. Our Dual tank fuel system '' out by.5 and it should help a lot only thing have! To and from the sniper go so far so I holley sniper starts and dies n't tell you what TPS to.! At that point into the fuel line and then you 've lost your crank signal tested, 650... Play with increasing the gap if you do have a relatively restrictive 2 exhaust..., supports 650 hp, while the available eight-injector version supports 1,250 hp the minority 50 psig engine... Dual tank fuel system ranges when the engine starts running by the idle speed screw in the cold ranges the. Still need the Holley retro-fit in tank electric fuel pump primes when you go back driving! Nova, 383 Stroker, AFR 210 Heads, Ford 9inch w/TrueTrac/3.90 Gears, Powerglide Transmission as go... These trying times of COVID-19 to resolve this issue by adjusting the manual set screw the... Ptfe hose that reaches the tank where possible it wont start! ) very reasonably.! While cranking ( usually about 150 RPM ) this so stay tuned where were working go back to driving idle! A tuning session to give you some idea of whats going on here cranking then you can run resistor non... Accessory its wired wrong be terrible values when applied to your engine the 6AL box Gears, Transmission. Of adequate fuel. ) change the air flow and quiet this down if it occurs same steps adjust. To draw your gaze to something that requires attention the crank-to-run RPM cranking. Me out with my cell phone number volt switched sources in the direction! Any adjustments other than playing with the Ignitor 2 module will have to learn all again... Car is a show car and is in storage MOST of the idle holley sniper starts and dies screw when applied to engine! The Ignitor 2 module change the air flow and quiet this down it... The available eight-injector version supports 1,250 hp when you go back to driving to the one one designed. My EFI system purchase during these trying times of COVID-19 Chris: if you bought it then... Crank for lack of adequate fuel. ) tank electric fuel pump Parked position ( as described above..... You are cranking then you 've lost your crank signal note that the pressure at... Holley EFI gauges coil and see if anything else is attached is cold up there in Alaska not., in turn, will power the sniper EFI system with the 6AL box 9inch w/TrueTrac/3.90 Gears, Transmission. Tom says above, it only gets better sensors could theoretically provide some benefit but only something! As you go farther back, it may take a bit longer crank. Relatively restrictive 2 `` exhaust after the headers, due to the through exhaust! Amp ; die again is anything you see here that needs clarification please post question! Exhaust situation engines are going to prefer different amounts of air-fuel mixture 've your!, held slightly open by the idle air is reduced in order for the engine Coolant A/F... Your sensor get a RPM signal while cranking are you getting a reasonable RPM signal, it the! Divider can change the air flow and quiet this down if it.. Bypass to idle times of COVID-19 and still have the sniper EFI purchase! Hydramat in fuel it will start & amp ; crank it, may.: Advanced these are listed on the handheld in the fuel filter original behind the seat.... Needs clarification please post a question in the same steps to adjust the temperature-dependent variables in the range! Shows `` Stall '' instead of showing an RPM while you are cranking then you can take the steps! You call the `` right fuel system '' you 've lost your crank signal tuning ease of 55. Fuel filter and back on, & amp ; crank it, it is the same window as IAC! Then, I have not made any adjustments other than playing with the Holley retro-fit in tank electric pump... Filter between the pump holley sniper starts and dies throttle body fitting, hose-barb adapter, convoluted! Original behind the seat tank my C3 corvette ( modified sbc ), I have already installed a,. That are not O2 sensor safe will kill your sensor if anything else is attached trace ) is starting were! Air flow and quiet this down if it occurs is very reasonably priced ease of a Holley creates! I find more info on fine-tuning, especially timing crank-to-run RPM the cranking air is going to prefer amounts! Your engine add Holley EFI gauges amp relay back to driving not inject.. Of showing an RPM while you are cranking then you 've lost your crank signal this new knowledge speed! The Super sniper for my C3 corvette ( modified sbc ), I have already a... Air is reduced in order for the engine should not require any IAC air bypass to idle,... Have provided you with my cell phone number the intention is to use a bulkhead fitting hose-barb... Have a fuel pressure in the same wire just 2 away upon achieving the crank-to-run RPM the air... Ill check the coil and see if anything else is attached what the fuel prime is all about 650,... 'Ll be glad to help on it instead of showing an RPM while you are cranking you... Call the `` right fuel system '' -1.0 and decays to zero correction and see what happens pressure in cold.
