Holley Sniper Stealth EFI - Part 3 (Starting Slowly)

I started today by removing the AutoMeter Sport Comp AFR gauge (ATM-3370) from under the dash that I've used for years to tune the carburetor.  I'd always planned to use it to tune and then remove it.  I was always questioning if it was right so the gauge stayed in place permanently.

I removed the wiring under the dash that fed power to the current electric fuel pump.  Instead of it running to an ignition source at the circuit panel, I ran it out the firewall to connect to the Sniper system.  I had coiled up all the extra wire from connecting it which made it more than long enough to reach under the hood.  The Sniper system will now tell the pump when to run.

Inside the car, I took apart the RAM mount I used to hold my phone on road trips and expect to use it as a mount for the Sniper display.  I used the 3M adhesive pads they provided and fastened the display mount to the RAM mount.  It holds it just under the radio which will be perfect.  When I don't plan to have it out any longer, I can put the cell phone holder back in place.

The last thing I did was pump all the fuel out of the tank, remove the existing fuel tank, and the fuel pump.  I expected to pump all the fuel out without making a mess of the floor but that didn't happen.  It started perfectly as I filled a 5 gallon gas can.  I left the hose in the can while I went to get a funnel to put the gas into another vehicle.  In the minute I walked away, the fuel line came out of the gas can, fell to the floor, and I suppose the siphon effect caused it to just keep pulling fuel as the entire floor was covered.  I thought I had laid the best plan.

I spent quite a while cleaning up the floor so that it didn't overwhelm me with gas fumes.  I'll be gone for work the next few days so I put the gas tank outside to vent and dry out.  When I return, I'll get back after it.  I might order a few small things between now and then to continue making progress.

Holley Sniper Stealth EFI - Part 2 (Parts Arrive)

The Holley Sniper Stealth EFI system arrived in the mail today.  I quickly opened it and spread out all the items that came as part of the kit.  I'll need much more to make this work but everything I expected to receive was included in the box.

I placed the throttle body on the intake and it seemed slightly taller.  With some quick measuring, I found the Sniper unit was a 1/4" taller than the Street Avenger carb.  I placed my air cleaner on and found that it now makes contact with the hood.  I've been using a 1/2" phenolic spacer which I can remove.  I added the spacer to address issues with vapor lock.  Since the Sniper doesn't have bowls to store fuel in, the spacer will have much less benefit.

I also noticed that due to the design of the top of the Sniper, the threaded hole for the air cleaner stud is lower.  As a result, my former air cleaner stud is too small.  I need one that has a 1/4"-20 thread pitch and that is hopefully around 3.5" long.  I'll add that to the list of things to purchase.

Before the Holley Stealth kit arrived, I decided to go ahead and purchase the gas tank I'll use with the Stealth EFI system.  I purchased a Tanks brand kit (TNK-MU-HT-KIT) which includes everything that I will need associated with the fuel tank.  The tank is a 16 gallon tank with internal baffles and is powder coated silver (TNK-MU-HT-KIT).  The tank came with the pump (TNK-GPA-4) and a Ford style sending unit (TNK-TAN-ORG).  Despite ordering the tank several days after the Stealth System, it arrived first.

Holley Sniper Stealth EFI - Part 1

After multiple attempts to adjust the carburetor, I ultimately lost motivation.  I adjusted the high idle screw on at least four different occasions with mixed results on the idle RPM.  Strangely, once it would start, it would often just slowly have the idle increase rather than decrease.  If you were to press the pedal to take it off high idle, it would just stay at the RPM you reached when briefly pressing the pedal.

Besides the high idle, I had another instance in which the accelerator pump didn't want to work with the new carburetor.  I can't explain it as the pump cam is unadjusted and seems fine.  The fuel bowls had fuel in them.  I took the pump nozzle off and then it didn't happen again but I can't imagine it was blocked.  It was another oddity that causes you to lose confidence in the plan.  

I've decided this winter that I'm going to work on upgrading the Mustang with a EFI system rather than continue to work through these carburetor troubles.  The money spent on the carburetor is somewhat wasted with this plan but I don't honestly care.  I'd like to work on the car again and want something that will reliably operate.

There are a few additional benefits beyond reliability.  The car has a hard start problem when hot despite fuel line insulation, carb spacers, and more.  The idle doesn't reliability adjust when the AC turns on.  The high idle has never worked causing the Mustang to often want to die for the first five minutes of driving.  Lastly, I'd rather not worry about adjusting the AFR to be right for the car and instead have a system that adjusts it automatically.

It is hard to continue to invest in the Mustang with the condition of the body and the paint.  However, I've about decided I'm going to get someone to restore the body and paint it.  I do want the car running reliability before I do that.  I'll then decide if I take it all apart to have it painted or how I handle the step in the process.

For today, I started by cleaning up the garage a bit to have a nice work area, removed the carburetor, and checked the wiring a little to pre-plan how the new Holley Sniper Stealth (550-870) will wire into the vehicle.  With those few things done, I placed the order for just the sniper unit as I don't expect to reliably place an order for everything I need and will just work through it bit by bit ordering parts as I need them to go get the job done.

I don't plan to rush and actually expect this to increase in scope and might include some rewiring.  I'll be happy if I the job is done around mid-February or early March when it is a good time to start driving around again.