The Powerjection III installs...
The Powerjection III installs just like a regular square-bore four-barrel carburetor. Check out the nice fuel rail that comes pre-installed on the PN 70026 and PN 70027 systems. The included fuel-pressure gauge is a nice feature, as is that little nipple on the fuel-pressure regulator, which can be hooked up to offer boost-referenced fuel metering for turbo or supercharged applications. The system can also be programmed to step up the fuel for nitrous, run E85 blended fuels, and countless other options.
| Engine |
Test 1 |
Test 2 |
| Speed |
| (rpm) |
Hp |
Tq |
Hp |
Tq |
| 3000 |
208 |
367 |
212 |
359 |
| 3200 |
220 |
361 |
219 |
360 |
| 3400 |
242 |
374 |
241 |
372 |
| 3600 |
262 |
383 |
264 |
385 |
| 3800 |
281 |
389 |
283 |
391 |
| 4000 |
301 |
395 |
303 |
398 |
| 4200 |
319 |
398 |
318 |
399 |
| 4400 |
332 |
397 |
330 |
394 |
| 4600 |
346 |
395 |
340 |
388 |
| 4800 |
359 |
393 |
353 |
386 |
| 5000 |
371 |
389 |
369 |
387 |
| 5200 |
381 |
384 |
378 |
382 |
| 5400 |
385 |
374 |
383 |
373 |
| 5600 |
386 |
362 |
385 |
361 |
| 5800 |
383 |
345 |
384 |
348 |
| 6000 |
383 |
336 |
387 |
339 |
| 6200 |
381 |
323 |
388 |
334 |
| 6400 |
375 |
308 |
380 |
311 |
We initially installed the...
We initially installed the PN 70026 Powerjection III on a Wieand dual-plenum Air Strike manifold, but experienced some fuel distribution problems we suspect stemmed from the intake charge stacking up at higher rpms with our stock cylinder heads and high-lift camshaft, so we swapped on this Professional Products single-plenum Hurricane manifold. Although the Hurricane shaved off a little torque, the upper rpm horsepower went up and the increased plenum volume helped mitigate our fuel puddling issues.
Test 1: Chevy 350 engine: Lunati Voodoo 227/233 @ 0.050, .489/.504 camshaft, Professional Products Hurricane intake, 1/2-inch phenolic carb spacer, Holley 4779 Double-Pumper carb, 37 degrees ignition timing, 13/4-inch long-tube headers
Test 2: Same as above with carburetor substituted for Powerjection III fuel injection
Peak values are in bold
Although you can crack into...
Although you can crack into the Powerjection III's software to manually tune the system, we didn't. Instead, we chose to let the system self-learn for a few minutes as the engine ran on the dyno to see how it stacked up against the dyno carburetor. However, if the need ever arises, we'll be able to compensate fuel delivery to adjust overall air/fuel ratio for a poorly-operating cylinder, run in open- or closed-loop mode, adjust fuel delivery in any given rpm range, compensate for different camshafts, intakes, or any tuning scenario you can imagine.
Top Twelve Tricks
The advantages are many, but here are our favorite points about the Powerjection III.
•There's no need to change out your ignition system. A tach signal from the ignition coil or ignition box is all that's required.
•There's no need to swap your intake manifold. The unit uses a standard four-barrel mounting flange, so you can use an affordable one- or two-barrel-to-four-barrel adapter if your intake manifold doesn't already have a square-bore, four-barrel flange.
•The throttle body works with standard carburetor throttle linkage and any off-the-shelf air cleaner with a 55/8-inch carb neck.
•There's no bulky computer to mount, since the computer is located in the throttle body itself.
•The wiring harness consists of only six wires, and technically you only need three of those to make the engine run.
•Comes with the fuel rail, adjustable pressure regulator, and fuel gauge already installed on the throttle body, as well as the correct fuel pump and filter supplied with the PN 70026 or PN 70027 systems. The regulator is pre-set at the required 45psi.
•If the engine stops running, the computer shuts off the fuel pump when the tach signal is lost, which can be beneficial if there's a rollover or crash.
•Four 62lb/hr injectors in the 930cfm throttle body supply enough fuel to feed 550hp, but can also work on small V-8 or V-6 engines. Injectors can be swapped out for smaller units to work with small four-cylinder engines or ordered with four 75lb/hr injectors for up to 600hp.
•It's designed to be installed by the home-hobbyist, so installation and setup are simple and almost everything is included (fuel lines and fittings aren't included, but can be ordered under PN 70107 from Professional Products). There's also no welding required to install the supplied O2 sensor in the exhaust.
•Parts are of high-quality and not Chinese-built junk.
•At roughly $1,500, it's one of the less-expensive systems available.
•There's no tuning necessary! Plug in your laptop , answer a couple of questions such as number of engine cylinders and peak torque, then just drive it. The system self-learns by itself.