55mike
07-30-2023, 07:54 PM
lt's been a bit of time since I've posted anything. Figured it was about time to give an update on my latest significant project on my 55. After much research, i decided to update my fuel delivery system with a Holley Sniper fuel injection system. I found EFI Systems Pro to be a good source for both the hardware and their subsequent tuning (at no extra charge). I am NOT an expert with FI, but, I reasoned I could install the system myself. EFI Systems Pro recommended the in-tank fuel module (sending unit, pump etc) , an Earl's fuel pressure gauge to be installed on the actual unit, and various fittings and hoses. Having this fuel module eliminates the need to a return line.
The install was pretty straightforward although I did end up using a relay directly from the battery (which is in the trunk) to power the (famous) "pink" wire that activates the computer. The issue was getting enough voltage during cranking. I read, and then studied the instructions, even printing the entire 70 page on-line manual. I had to extend some the wires to the battery, and I chose to use the temperature port in the cylinder head which meant extending that wire. The Sniper also controls the twin spal fans. I also chose to just use my MSD distributor, 6a box and master blaster coil. In other words, the Sniper doesn't control the timing.
It took me several weeks to install mainly due to retro-fitting to a running car, and the fact I really took my time. I used Grote brand connectors (they are both crimp and heat shrink) plus I put extra heat shrink on every joint along with Faraday cloth on several of the joints. I spent considerable time to route wires away from any RF sources.
The system is working flawlessly. EFI Systems Pro has done two remote tunes (via SD card and email attachments). i am very pleased with how the engine runs. Tip-in is smooth and drama-free. The WOT power seems to be on par with the Demon carb I was running. MPG are about the same, but, I'm hoping as it is tuned and "learns" it will improve. So far, I've seen about 16 or so MPG on the hwy. Not terrible for my combination. .. but I'm hoping for better.
Lessons learned... I needed to update the alternator to a 140 amp model to keep up with the A/C, EFI, headlights, stereo system etc...
The old harmonic balancer was failing. Yes, failing. The mark on the balancer when on the strobe would "walk" making a true timing reading impossible. I replaced the balancer, and that fixed that. Although I had the 02 bung welded in, I had an exhaust leak both at the bung and at the header collector. EFI Systems Pro could see this when I sent my first data file for their tune. To check this, I pressurized the pipe with my wet/dry vacuum and sprayed soap water around and sure enough found bubbles. This was all repaired.
My message is, Sniper FI isn't a bad choice.. I've read where others hate them, but, for me, I'm loving it. Holley has come out with "Sniper-2" which is supposed to correct some of the issues as well.
The install was pretty straightforward although I did end up using a relay directly from the battery (which is in the trunk) to power the (famous) "pink" wire that activates the computer. The issue was getting enough voltage during cranking. I read, and then studied the instructions, even printing the entire 70 page on-line manual. I had to extend some the wires to the battery, and I chose to use the temperature port in the cylinder head which meant extending that wire. The Sniper also controls the twin spal fans. I also chose to just use my MSD distributor, 6a box and master blaster coil. In other words, the Sniper doesn't control the timing.
It took me several weeks to install mainly due to retro-fitting to a running car, and the fact I really took my time. I used Grote brand connectors (they are both crimp and heat shrink) plus I put extra heat shrink on every joint along with Faraday cloth on several of the joints. I spent considerable time to route wires away from any RF sources.
The system is working flawlessly. EFI Systems Pro has done two remote tunes (via SD card and email attachments). i am very pleased with how the engine runs. Tip-in is smooth and drama-free. The WOT power seems to be on par with the Demon carb I was running. MPG are about the same, but, I'm hoping as it is tuned and "learns" it will improve. So far, I've seen about 16 or so MPG on the hwy. Not terrible for my combination. .. but I'm hoping for better.
Lessons learned... I needed to update the alternator to a 140 amp model to keep up with the A/C, EFI, headlights, stereo system etc...
The old harmonic balancer was failing. Yes, failing. The mark on the balancer when on the strobe would "walk" making a true timing reading impossible. I replaced the balancer, and that fixed that. Although I had the 02 bung welded in, I had an exhaust leak both at the bung and at the header collector. EFI Systems Pro could see this when I sent my first data file for their tune. To check this, I pressurized the pipe with my wet/dry vacuum and sprayed soap water around and sure enough found bubbles. This was all repaired.
My message is, Sniper FI isn't a bad choice.. I've read where others hate them, but, for me, I'm loving it. Holley has come out with "Sniper-2" which is supposed to correct some of the issues as well.