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Our second segment in this two-part build series starts off right where we ended off. Blue Sky Performance and Restoration of Budd Lake, New jersey installed a complete Holley Sniper EFI upgrade into this Paxton huffed, 360ci powered 1965 Plymouth Barracuda. Jeff Manzella, head mechanic and co-owner of Blue Sky showed why he’s the best at what he does. Now Jeff will do his best to tame this beast by tuning this Mopar A-Body up with the newfound fuel injection to reach peak performance perfection!
In the first segment of our Super Sniper EFI Stealth installation, we showed how we upgraded our formerly carbureted 360 with a complete set-up of choice Holley products. We started by added a Holley Dominator single plane intake to the block, and then installed the new throttle body up top. We went with the Sniper fuel tank out back and finished it all off with a Holley Hyperspark coil, a Holley bypass fuel regulator, and a Holley Pro Billet distributor.
How can I convert my classic car to electronic fuel injection?
With all of the installation complete, we have a Barracuda that’s ready to finally move as fast as the fish it is named after. Now that we have got the car running under naturally aspirated conditions, we are now ready to button everything up and see what the Paxton supercharger can do.
Jeff will first get the Barracuda running consistently and then tune the car on their in-house dynamometer, hoping to squeeze a few more horsepower from this small-block predator. Knowing what Jeff and the guys at Blue Sky have done in the past, we know this A-body is in good hands. Let’s see what happens!
This is where we left off from the last installment. We had just finished the installation of the Holley Super Sniper EFI Stealth and were preparing to get the engine running. Here, Manzella uses the tuning wizard in the Holley handheld to set up the initial engine and ignition settings.
Manzella checks the base setting with the desktop software to confirm everything has generated correctly.
You’ll find that there are options when setting up your kit. Here we switch the map sensor to read in PSI from KPA, which is the shop’s personal preference.
Amazingly, it only took just a little coaxing for the engine to spring to life, as it hasn’t ran much over the last few years. Manzella now checks the base timing so we can make sure the computer and the engine are synced properly.
After checking the timing, Manzella discovers that the engine timing is not correctly synced with the computer timing. Using the computer, Manzella offsets the timing to sync the engine to the computer. He then flashes the changes made on the computer to the Holley Sniper throttle body.
Manzella once again checks the timing to confirm the changes made on the computer followed to the engine.
Because of interference from the throttle body float adjustment screws, Manzella needed to grind out more clearance on the top hat base using a mini-belt sander. This step is a must as a good seal between the throttle body and air cleaner base is needed to keep all the boost in the engine.
Tightening the silicone coupler to the charge pipe and battening down the hatches on the Paxton set-up…we are almost ready to make some boost!
Here’s the finished product. Everything fits nicely under the hood. Hard to tell we made any changes as the Super Sniper EFI Stealth blends in well.
Manzella readies the in-house dynamometer. All the vehicle information needs to be entered before we do any pulls and engine tuning.
After the first dyno run, Manzella pulls the plugs on the Barracuda to do a read on them. We can tell by the coloring of each plug that we have the proper fuel mixture. Also, we are looking at the strap on the spark plug to verify that ignition timing is in a safe area. Everything looks as good as it’s gonna get.
Since it was determined that we were in a “safe zone”. Manzella says we can now add two degrees of ignition timing to hopefully make more power.
On to the dyno pulls. From here it is a combination of first tuning the fueling to the engine and then adjusting the timing to get the most reliable power we can out of the engine. We did approximately 12 runs over the course of the afternoon.
The final numbers are in! We made we made 322 horsepower and 379.5 lb-ft of torque to the tires running on only 4 PSI of boost. Typically, we will see automatic drivetrains lose about 15-20% of their engine horsepower through parasitic drivetrain loss. With the engine previously charting at 402 crank horsepower when first built, everything seems happy on our front.
Driving this revamped Barracuda has become a series of thrills instead of a cycle of ills. The 360 starts right up without hesitation now and idles like a dream. Stop lights and stop signs are no longer a horror show using two feet and the throttle response is nothing but stellar.
We’d like to thank Blue Sky Performance and Restoration for helping with this build.