I bought a Sniper for my 350 Nova in August of 2022. I'm replacing my tried-and-true Holley 650 double pumper which has worked well for a long time. Putting it on now Feb 2023. I was concerned about all 4 barrels opening at once. I just bought the short link and worried about the needed firmware version process. I'll look for the latest firmware and load it. Great video, thank you.
Hey, thanks for watching. I replaced the 650 DP as well. Such a great carb, but it just can't do what the sniper does unfortunately. The fixed link gives you the pedal feel of the double pumper but, if configured correctly, doesn't change the total fuel distribution in comparison to the "all 4 barrels" mode. The sniper simply sprays more fuel out of the initial 2 barrels and then when it hits the 4 barrel opening throttle % it starts weening off the first 2 barrels to give you the proper total fuel out of the barrels based on how open they are. Perhaps I made that more co fusing than it has to be, but the point is, the sniper is smart enough to use the right amount of fuel regardless if it's in stock or fixed link configuration. I think you'll find the software changes fairly straight forward if you follow the video.
Well done and thank you for posting this! My 77 C10 with the Sniper was wanting to launch from every stop! This answered the question as to why. I'll be getting a secondary adjustment from Holley ASAP! Again thank you for putting this out there!
Glad you found the video informative. Just keep in mind adding the linkage doesn't necessarily reduce fuel intake off the line, but can increase the throttle feel off the line. It will put you down to 2 barrels, but those 2 barrels will put out more fuel to compensate not running on all 4 barrels like the stock setup. It's worth a try for you, but your real issue may be low rpm fuel tables.
Great video, I learned a lot. I just installed a Holley EFI unit on my 327 small block. It has a severely bad lurch off the line virtually undrivable (Unless you're racing...LOL). This looks to be the perfect fix.
I know all this kinks have been worked out by now, I'm sure, if there were any. However, for anyone looking into this as I am with my Sniper system I also saw on another video an adjustment for the Acceleration Enrichment. Based on the other video, without also doing an adjustment there, you would still be spraying fuel into your secondaries, but with no airflow.
I looked at a couple of other YT clips concerning the progressive linkage for the Sniper system where they did use the "correct" fixed linkage. In those video's the fixed linkage made the secondaries open at 47% . . . . In one of them, the linkage was also "shoehorned" to get closer to 40%.
Ok so I tried this progressive linkage and the way you have it set up it's almost 3/4 like 37 or 40% throttle before seconderies kick in ..what I ended up doing is using the original part an straightening it out so it had a slight delay more like 15% and you can still feel the g force..works great happy burnouts
Glad you re-worked it into a good design. Once I had the new part I figured I coulda done the same, but I'm happy with the 40% secondaries. I really appreciate the mechanical aspect of this mod.
Thanks for the video. I had the same issue on my Mustang, basically the TPS jumped from 10% - 20% no matter how gentle I was on the pedal. How long did it take for the fuel maps to "re-learn" the mid-range transition?
@@TurboCamaro67 Part # 20-16 If you're running the FAST throttle cable bracket, (which seems popular and works great with Holley Sniper) you'll need to clearance the FAST bracket a little. www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_efi_service_components/parts/20-16
I tried the extension and it was still not pleasant to drive. Now I have the extension, progressive linkage, and a spring. It drives like factory now 🤘🏻
Bent mine the way you did originally from 47 to 40. Didn’t like the way the rod contacted the linkages… at an angle that will eventually wear rod or hole unevenly. Straighten rod back out then bend rod “up” in middle so contact points would stay parallel to each other.
Good question, I think it would have been better to have them come with the linkage but then provide a kit to make them open simultaneously. Must have been an afterthought.
Water meth is sprayed in before Holley (have posted video on that system). WOT with linkage is same as without linkage. It just allows better control over low end acceleration.
I'm not sure what you mean, it's more of a pedal feel upgrade than much of a mechanical improvement. I personally really like it, but it really just turns a fixed 4 barrel throttle body so that it has a mechanical secondaries feel.
@@TurboCamaro67 im thinking in terms of map. The thing is rated for 650hp,(mine being~400hp) so i figure its gunna cause a dip in vac when both blades are 100% open off idle. My cam is get 9.5" at 1100 rpm. I dont understand the tbi stuff very well
Hmmm, with the link installed and configured correctly in the software, the system will adjust the amount of fuel required to the "mains" side instead of dumping fuel into the side that isn't open yet. So you would need to press the pedal further to see the same amount of air/fuel/vacuum that you would without the link. So it's not so much an increase or decrease as their ratio is the same, it's more about increasing pedal feel/sensitivity. Gives you greater control of the fuel delivery with your foot. I'm not sure if you'd notice a difference in vacuum readings, other than in relation to throttle % but I don't think that would matter much.
The sniper has been the best upgrade. I've had zero issues with it. I would recommend the platform for anyone looking to get into FI from a carb setup.
@@tylerelders227 yes it is in the wizard setting somewhere to adjust it to cut until a specific % throttle but to really get it setup correctly across the power band you may want to save the settings to a microSD card and hook it up to a computer.
@@rfeldtz I adjusted the TPS to 40% secondary, but I heard that still sends fuel, unless you change AE/TPS or something with a laptop.?.?..? I need to adjust my valves but want to tyne this thing proper...
Stupid question of the day--- I'm getting around 10 miles to the gallon on a 1970 C10 with the unit, this new setup should increase the mileage, right--?
Theoretically; yes. Specially under (mild) acceleration. But if you always smash the throttle past 40% while accelerating, it will not. During cruise it shouldn't matter as the engine will always want to have that same x amount of fuel (and air) to do the job correctly at that specific speed/condition.
@@renekooger2060 my throttle responds with just the very slightest pressure, literally one or two inches , it's my daily driver also my often wallet open up er-- thank you for your time---
Yeah, if your AFR is set right you should/could have better milage than a carb. However if the carb was well adjusted or lean, their's no guarentee mileage will improve.
@@TurboCamaro67 just got the truck about 6 months ago, had the injector installed by a mechanic, I'm not much of a car guy except I feel in love with the truck, this is my retirement gift to myself, it has the looks of Raquel Welch but needed work under the hat, I'm trying to learn and understand how to make minor adjustments to it.
This causes issues. Holley engineers aren't dumb. Buy the throttle lever extension. At wot your car is dumping a ton of fuel into the Holley but since the rears do not open up all the way your car is going to run rich at high rpm since the rear throttle blades aren't fully open
Yes, the part I used was the official Holley part. However, when I bought it and made the video it was a recent release and Holley did not have stock on their website, so I used my preferred outlet.
@@TurboCamaro67 i thought this one was home brew and the adjustable one was the "official" part. didnt realize holley made both flavors...cool of them to give ya a cheaper option.
@@DieselRamcharger Interesting, I didn't know Holley made an adjustable one. I suspect they started with the fixed link and then came out with the adjustable. I love the idea of an adjustable one.
What kind of horse power are ya squeezing out of that 250. ??? Ya EFI is definitely a step in the right direction for turbocharged engines. Thanks for the information.
Roger Marshall Hard to know for sure without dyno'ing it yet. People smarter than I have estimated around 400HP at 8#'s boost. Probably slightly more torque. I've had a 327 and a mildly built 350 and this car, while lighter, would have had no issue leaving them in the mirror.
MUCH better to make or buy Holley throttle linkage extension… reprograming of Sniper with progressive linkage, it never ran well, linkage arm solved problem. 5 minute bolt on. Holley part # 20-16
I used the arm it still was crap. I run the arm and progressive linkage now and it's perfect. The reprogramming was like 5 clicks on the handheld too, not difficult at all.
Hey, yeah I've seen their linkage. I've been running this EFI System Pro linkage for 5+ years and can confirm it works great for me. Smoother acceleration and better throttle response as a daily driver for sure. I'm not surprised Holley recommends their own, more expensive products.
I bought a Sniper for my 350 Nova in August of 2022. I'm replacing my tried-and-true Holley 650 double pumper which has worked well for a long time. Putting it on now Feb 2023. I was concerned about all 4 barrels opening at once. I just bought the short link and worried about the needed firmware version process. I'll look for the latest firmware and load it. Great video, thank you.
Hey, thanks for watching. I replaced the 650 DP as well. Such a great carb, but it just can't do what the sniper does unfortunately. The fixed link gives you the pedal feel of the double pumper but, if configured correctly, doesn't change the total fuel distribution in comparison to the "all 4 barrels" mode. The sniper simply sprays more fuel out of the initial 2 barrels and then when it hits the 4 barrel opening throttle % it starts weening off the first 2 barrels to give you the proper total fuel out of the barrels based on how open they are. Perhaps I made that more co fusing than it has to be, but the point is, the sniper is smart enough to use the right amount of fuel regardless if it's in stock or fixed link configuration. I think you'll find the software changes fairly straight forward if you follow the video.
I like it glad you kept the six in it
Well done and thank you for posting this! My 77 C10 with the Sniper was wanting to launch from every stop! This answered the question as to why. I'll be getting a secondary adjustment from Holley ASAP! Again thank you for putting this out there!
Glad you found the video informative. Just keep in mind adding the linkage doesn't necessarily reduce fuel intake off the line, but can increase the throttle feel off the line. It will put you down to 2 barrels, but those 2 barrels will put out more fuel to compensate not running on all 4 barrels like the stock setup. It's worth a try for you, but your real issue may be low rpm fuel tables.
Great video, awesome simple details. Thank you
Great video, I learned a lot. I just installed a Holley EFI unit on my 327 small block. It has a severely bad lurch off the line virtually undrivable (Unless you're racing...LOL). This looks to be the perfect fix.
I had the exact same issue on my 327 as well! throttle was crazy sensitive.
I know all this kinks have been worked out by now, I'm sure, if there were any. However, for anyone looking into this as I am with my Sniper system I also saw on another video an adjustment for the Acceleration Enrichment. Based on the other video, without also doing an adjustment there, you would still be spraying fuel into your secondaries, but with no airflow.
not how it works. it's an algorithm based on throttle position and air flow that determins the injector pulse width
Cool car! I am going to do the same on my 63 Chevy II. Thanks for sharing 😃
That's not a good fix..its all in idle screw
Just did this per your video ! thanks :)
I looked at a couple of other YT clips concerning the progressive linkage for the Sniper system where they did use the "correct" fixed linkage. In those video's the fixed linkage made the secondaries open at 47% . . . .
In one of them, the linkage was also "shoehorned" to get closer to 40%.
if you get the right part from holley its adjustable. no bendy bendy.
Ok so I tried this progressive linkage and the way you have it set up it's almost 3/4 like 37 or 40% throttle before seconderies kick in ..what I ended up doing is using the original part an straightening it out so it had a slight delay more like 15% and you can still feel the g force..works great happy burnouts
Glad you re-worked it into a good design. Once I had the new part I figured I coulda done the same, but I'm happy with the 40% secondaries. I really appreciate the mechanical aspect of this mod.
Nice mod.
Can't wait to get my Holley on. Will have to do this mod also
Yeah, probably one of the cheapest mods with the biggest changes. Highly recommended.
Good stuff mate
I just installed Holley Sniper on a 67 Camaro with a ZZ502 in it. How to get it setup. Thanks for the help.
Thanks for the video. I had the same issue on my Mustang, basically the TPS jumped from 10% - 20% no matter how gentle I was on the pedal. How long did it take for the fuel maps to "re-learn" the mid-range transition?
i just straightened the bend in the original rod and it sits around 15% before secondary's start to open
Holley makes a throttle lever extension that helps with the pedal effort. If anyone needs the part number just ask, I'll look it up.
Hey, thanks for providing this info. I know my pedal is great but I've rigged the springs up for the right tension. Someone else may need it for sure.
@@TurboCamaro67 Part # 20-16 If you're running the FAST throttle cable bracket, (which seems popular and works great with Holley Sniper) you'll need to clearance the FAST bracket a little. www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_efi_service_components/parts/20-16
I tried the extension and it was still not pleasant to drive. Now I have the extension, progressive linkage, and a spring. It drives like factory now 🤘🏻
I'd like to make a safety-based suggestion: A dual throttle-return spring.
Bent mine the way you did originally from 47 to 40. Didn’t like the way the rod contacted the linkages… at an angle that will eventually wear rod or hole unevenly. Straighten rod back out then bend rod “up” in middle so contact points would stay parallel to each other.
Yeah good call, I ended up adjusting mine some too. Always playing with these things on custom builds.
I've ordered the kit to do this.
I wonder why they don't build it this wayto start with - just like carbs are?
Good question, I think it would have been better to have them come with the linkage but then provide a kit to make them open simultaneously. Must have been an afterthought.
Are you spraying your water meth before or after the holley? Does the linkage change affect wide open throttle?
Water meth is sprayed in before Holley (have posted video on that system). WOT with linkage is same as without linkage. It just allows better control over low end acceleration.
@@TurboCamaro67 thanks, ill have to check out the video 👍🏻
Will it improve the vacuum signal if you got a big cam?
I'm not sure what you mean, it's more of a pedal feel upgrade than much of a mechanical improvement. I personally really like it, but it really just turns a fixed 4 barrel throttle body so that it has a mechanical secondaries feel.
@@TurboCamaro67 im thinking in terms of map. The thing is rated for 650hp,(mine being~400hp) so i figure its gunna cause a dip in vac when both blades are 100% open off idle. My cam is get 9.5" at 1100 rpm. I dont understand the tbi stuff very well
Hmmm, with the link installed and configured correctly in the software, the system will adjust the amount of fuel required to the "mains" side instead of dumping fuel into the side that isn't open yet. So you would need to press the pedal further to see the same amount of air/fuel/vacuum that you would without the link. So it's not so much an increase or decrease as their ratio is the same, it's more about increasing pedal feel/sensitivity. Gives you greater control of the fuel delivery with your foot. I'm not sure if you'd notice a difference in vacuum readings, other than in relation to throttle % but I don't think that would matter much.
So 2 years later, is the Sniper working reliably? Any long term issues you've found with it? I'm considering it for my fox body.
The sniper has been the best upgrade. I've had zero issues with it. I would recommend the platform for anyone looking to get into FI from a carb setup.
I have version 1.1.33 software. How do I make this linkage work with my software, or how do I download the older version?
I would imagine the linkage can be used on any software newer than mine. Otherwise the instructions should be the same.
Just an FYI you should copy your setup to sad then load it o the computer and shut off the fuel to the secondaries until 40%
Hmm.. I have made so many adjustments to my config since this video that I'm not sure what it's set to now. Thanks for sharing this.
Can you fix the secondary fuel without a laptop???
@@tylerelders227 yes it is in the wizard setting somewhere to adjust it to cut until a specific % throttle but to really get it setup correctly across the power band you may want to save the settings to a microSD card and hook it up to a computer.
@@rfeldtz I adjusted the TPS to 40% secondary, but I heard that still sends fuel, unless you change AE/TPS or something with a laptop.?.?..? I need to adjust my valves but want to tyne this thing proper...
Stupid question of the day--- I'm getting around 10 miles to the gallon on a 1970 C10 with the unit, this new setup should increase the mileage, right--?
Theoretically; yes.
Specially under (mild) acceleration.
But if you always smash the throttle past 40% while accelerating, it will not.
During cruise it shouldn't matter as the engine will always want to have that same x amount of fuel (and air) to do the job correctly at that specific speed/condition.
@@renekooger2060 my throttle responds with just the very slightest pressure, literally one or two inches , it's my daily driver also my often wallet open up er-- thank you for your time---
Yeah, if your AFR is set right you should/could have better milage than a carb. However if the carb was well adjusted or lean, their's no guarentee mileage will improve.
@@TurboCamaro67 just got the truck about 6 months ago, had the injector installed by a mechanic, I'm not much of a car guy except I feel in love with the truck, this is my retirement gift to myself, it has the looks of Raquel Welch but needed work under the hat, I'm trying to learn and understand how to make minor adjustments to it.
Great video, lots of good information. Oh and I tend to beat my gear into submission too .................. LOL
John Parrish Sometimes you need to show it who's boss 😅
What is your max boost set at? What is the Water/Meth injection boost pressure set at?
John Parrish the boost goes to 8psi and the water/meth combo starts shooting at 3psi.
This causes issues. Holley engineers aren't dumb. Buy the throttle lever extension. At wot your car is dumping a ton of fuel into the Holley but since the rears do not open up all the way your car is going to run rich at high rpm since the rear throttle blades aren't fully open
you know holley sells this......right?
Yes, the part I used was the official Holley part. However, when I bought it and made the video it was a recent release and Holley did not have stock on their website, so I used my preferred outlet.
@@TurboCamaro67 yup no shame in that game.
@@TurboCamaro67 i thought this one was home brew and the adjustable one was the "official" part. didnt realize holley made both flavors...cool of them to give ya a cheaper option.
@@DieselRamcharger Interesting, I didn't know Holley made an adjustable one. I suspect they started with the fixed link and then came out with the adjustable. I love the idea of an adjustable one.
What kind of horse power are ya squeezing out of that 250. ??? Ya EFI is definitely a step in the right direction for turbocharged engines. Thanks for the information.
Roger Marshall Hard to know for sure without dyno'ing it yet. People smarter than I have estimated around 400HP at 8#'s boost. Probably slightly more torque. I've had a 327 and a mildly built 350 and this car, while lighter, would have had no issue leaving them in the mirror.
MUCH better to make or buy Holley throttle linkage extension… reprograming of Sniper with progressive linkage, it never ran well, linkage arm solved problem. 5 minute bolt on. Holley part # 20-16
I used the arm it still was crap. I run the arm and progressive linkage now and it's perfect. The reprogramming was like 5 clicks on the handheld too, not difficult at all.
Holley doesn't recommend this. There is a throttle linkage that will help problem and allow all four barrels to open without the resistance.
Hey, yeah I've seen their linkage. I've been running this EFI System Pro linkage for 5+ years and can confirm it works great for me. Smoother acceleration and better throttle response as a daily driver for sure. I'm not surprised Holley recommends their own, more expensive products.
Why isn't someone making this linkage for like $10?? It's the most overpriced product ever, ya know?