C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Holley sniper efi

Thread Tools
 
Search this Thread
 
Old Jul 15, 2018 | 11:50 AM
  #1  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Holley sniper efi

i purchased a sniper master kit and in stalled on my garage floor over 3 day period making sure everything looked professional and clean. Fired right up and ran great, car is a 383 stroker 440 hp 480 torque and the idol was amazing with no raw fuel fumes like withe the Quadrajet. Car was still in learning phase When I was about to test drive and it cut off. Went through all the set up directions again and still no start, could hear fuel pump cycle for 5 seconds but the injectors are not priming up for starting. Called Holley tec for help and did few thing to no help. Was told they believe it fuel pressure issue. Built in fuel pressure regulator is set at 58 psi. I purchased a fuel pressure test kit from harbor freight and tested and pump will only build 10 psi on each 5 second cycle and I did that 5-6 times and will only reach 35 psi. So bad fuel pump with only 20-30 minutes run time on it. In line gauge is a good option . Hope this will help someone one if they run in to this.
Robert
USMC Retired
Old Jul 15, 2018 | 12:30 PM
  #2  
MelWff's Avatar
MelWff
Race Director
20 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2006
Posts: 18,784
Likes: 2,598
Default

what year car is this installed on, your profile and picture dont show a C3?
Old Jul 15, 2018 | 03:25 PM
  #3  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Efi




77 vette
Old Jul 16, 2018 | 09:05 AM
  #4  
BlowAMouse's Avatar
BlowAMouse
Racer
10 Year Member
 
Joined: Nov 2011
Posts: 285
Likes: 36
From: Cedar Park TX
Default

Originally Posted by MelWff
what year car is this installed on, your profile and picture dont show a C3?
Had same no start issue with mine. Put inline gauge in and found only 20psi..............OUT OF GAS I WAS

Old Jul 16, 2018 | 11:48 AM
  #5  
Rescue Rogers's Avatar
Rescue Rogers
Is my vette stock?? HAHA
Supporting Lifetime Gold
Veteran: Navy
10 Year Member
Community Builder
Loved
 
Joined: Oct 2015
Posts: 20,287
Likes: 9,418
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Default

pics of your setup please?
Old Jul 16, 2018 | 01:43 PM
  #6  
ajrothm's Avatar
ajrothm
Le Mans Master
15 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Default

Originally Posted by BlowAMouse
Had same no start issue with mine. Put inline gauge in and found only 20psi..............OUT OF GAS I WAS
I can believe that....lol
Old Jul 16, 2018 | 02:45 PM
  #7  
BlowAMouse's Avatar
BlowAMouse
Racer
10 Year Member
 
Joined: Nov 2011
Posts: 285
Likes: 36
From: Cedar Park TX
Default

Originally Posted by Rescue Rogers
pics of your setup please?
Well.. the set up is on my 67 Camaro and currently do not have any pictures. The set up on the vette is my avatar
Old Jul 16, 2018 | 11:21 PM
  #8  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default EFI on 77 vette

Originally Posted by Rescue Rogers
pics of your setup please?




Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Corvettes to Drive Before You Die!

 Joe Kucinski
story-1

Corvette & Porsche 911: How Two Icons Conquered the Last 25 Years

 Joe Kucinski
story-2

2027 Chevrolet Silverado 1500 First Look: Everything You NEED to Know!

 Michael S. Palmer
story-3

5 Best & 5 Worst Corvette Daily Drivers

 Joe Kucinski
story-4

The Headlights of Every Corvette Generation Explained

 Joe Kucinski
story-5

5 Best & 5 Most Overrated Corvette Track Packages of All Time!

 Joe Kucinski
story-6

Every 2027 Corvette Engine Explained

 Joe Kucinski
story-7

Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

 Verdad Gallardo
story-8

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-9

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
Old Jul 17, 2018 | 03:08 PM
  #9  
scottjamison's Avatar
scottjamison
Burning Brakes
 
Joined: May 2017
Posts: 774
Likes: 375
From: Seattle WA
Default

Did you have to do any special wiring or changes to get it working with the HEI distributor?
Old Jul 18, 2018 | 08:13 PM
  #10  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Efi

Originally Posted by scottjamison
Did you have to do any special wiring or changes to get it working with the HEI distributor?
No just hook up one wire to the tac wire and you are set.
Old Jul 18, 2018 | 08:33 PM
  #11  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Holley sniper efi



I got my replacement fuel pump in today and put it together and no luck car still not running.
I took fuel line off of throttle body and put fuel pressure gauge again and this one is only 22 psi max. I am lost on what it could be, could I have gotten another bad pump? I checked ground again to confirm it was good and check all the lines to make sure there is no kinks. I used the factory 3/8 metal line, I even put the pressure gauge at the pump to verify its not the lines and it's still 22psi.
Old Jul 19, 2018 | 02:07 AM
  #12  
glparrish's Avatar
glparrish
3rd Gear
 
Joined: Jul 2018
Posts: 3
Likes: 0
Default

Have a few questions about fuel and return line, along with gas tank.

What gas tank did you go with, or did you adapt the existing one to make it work?

Did you run fuel lines down the rails with the flex hose, or connect it to the factory hard lines running down the passenger side?

What did you do for return line?

About to pull the trigger on this and these are quesitons i have.

THANKS!
Old Jul 19, 2018 | 05:50 AM
  #13  
OzzyTom's Avatar
OzzyTom
Burning Brakes
20 Year Member
Liked
 
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
Default

You could you have a blocked vent port on the tank.
remove the gas tank cap and see if the fuel pressure rises....
just a quick simple check to eliminate that as the issue.
Old Jul 19, 2018 | 07:31 AM
  #14  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Efi

Originally Posted by glparrish
Have a few questions about fuel and return line, along with gas tank.

What gas tank did you go with, or did you adapt the existing one to make it work?

Did you run fuel lines down the rails with the flex hose, or connect it to the factory hard lines running down the passenger side?

What did you do for return line?

About to pull the trigger on this and these are quesitons i have.

THANKS!
I used the factory fuel lines and connected where the tank lines and metal lines coming from rail meet. Used the factory tank and return line I used the factory 5/16 line that runs along with the fuel line.
Old Jul 19, 2018 | 07:44 AM
  #15  
2mnyvets's Avatar
2mnyvets
Racer
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2015
Posts: 396
Likes: 101
From: Lehigh Valley Pennsylvania
Default

Can you run the pump inlet hose to a 2 gal portable gas tank and try it? This would eliminate all the screens, connections and vents in the tank itself. Sounds like it is either 2 bad pumps or a restriction in the tank/ inlet. .
Old Jul 19, 2018 | 10:06 AM
  #16  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Efi

Originally Posted by 2mnyvets
Can you run the pump inlet hose to a 2 gal portable gas tank and try it? This would eliminate all the screens, connections and vents in the tank itself. Sounds like it is either 2 bad pumps or a restriction in the tank/ inlet. .
I did just what you said and had 97psi and blew in tank line and connected back and got 40psi. Pump is sucking strainer closed. Draining tank now so I can drop it and put new strainer on. Thanks for your reply to my frustration Sir. I feel better now at least knowing whats wrong.

Last edited by edusmc1; Jul 19, 2018 at 10:07 AM.
Old Jul 19, 2018 | 11:58 AM
  #17  
79 C3's Avatar
79 C3
Advanced
 
Joined: May 2015
Posts: 72
Likes: 4
From: Alvin Texas
Default

I sometimes have the same problem with my Fitech. I have my pump and filter like yours and my lines coming from my tank from the original outlet. If the pump does not have a good head pressure on it I get a vapor lock in the pump. I have to take the line off and prime the pump to get the pressure back up to EFI pressures. I will soon be replacing the intake screen with a Holley Fuel Mat to see if this helps and low tank levels.

Get notified of new replies

To Holley sniper efi

Old Jul 19, 2018 | 12:01 PM
  #18  
Rescue Rogers's Avatar
Rescue Rogers
Is my vette stock?? HAHA
Supporting Lifetime Gold
Veteran: Navy
10 Year Member
Community Builder
Loved
 
Joined: Oct 2015
Posts: 20,287
Likes: 9,418
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Default

let me know how the stock return line works. I've read it should be 3/8s but if the 5/16 will work that is less to change
Old Jul 19, 2018 | 02:35 PM
  #19  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default REturn line

Originally Posted by Rescue Rogers
let me know how the stock return line works. I've read it should be 3/8s but if the 5/16 will work that is less to change
I called Holley first and they said as long as you have at least 5/16 line there’s no problem. That’s why I used it. It just for return fuel from Tbilisi to tank and has little to no psi on it.
Old Jul 19, 2018 | 02:38 PM
  #20  
edusmc1's Avatar
edusmc1
Thread Starter
Instructor
10 Year Member
 
Joined: Apr 2009
Posts: 175
Likes: 12
From: Jacksonville NC
Default Efi

Originally Posted by Rescue Rogers
let me know how the stock return line works. I've read it should be 3/8s but if the 5/16 will work that is less to change
Originally Posted by 79 C3
I sometimes have the same problem with my Fitech. I have my pump and filter like yours and my lines coming from my tank from the original outlet. If the pump does not have a good head pressure on it I get a vapor lock in the pump. I have to take the line off and prime the pump to get the pressure back up to EFI pressures. I will soon be replacing the intake screen with a Holley Fuel Mat to see if this helps and low tank levels.
i believe my problem is the pick up strainer in tank collapse when pump kick on shouts down fuel flow because the suction make strainer collapse.


Last edited by edusmc1; Jul 20, 2018 at 07:52 AM.



All times are GMT -4. The time now is 08:56 AM.

story-0
10 Corvettes to Drive Before You Die!

Slideshow: 10 Corvettes to drive before you die.

By Joe Kucinski | 2026-06-23 08:31:12


VIEW MORE
story-1
Corvette & Porsche 911: How Two Icons Conquered the Last 25 Years

Slideshow: Corvette and Porsche 911, how two icons conquered the last 25 years.

By Joe Kucinski | 2026-06-23 08:18:33


VIEW MORE
story-2
2027 Chevrolet Silverado 1500 First Look: Everything You NEED to Know!

Slideshow: Is the 2027 Chevrolet Silverado 1500 the best Silverado yet?

By Michael S. Palmer | 2026-06-16 08:01:12


VIEW MORE
story-3
5 Best & 5 Worst Corvette Daily Drivers

Slideshow: 5 best and 5 worst Corvette daily drivers

By Joe Kucinski | 2026-06-15 10:32:13


VIEW MORE
story-4
The Headlights of Every Corvette Generation Explained

Slideshow: The headlights of every Corvette generation explained

By Joe Kucinski | 2026-06-15 10:17:14


VIEW MORE
story-5
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-6
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-7
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-8
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-9
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE