Our Ford Racing Performance...
Our Ford Racing Performance Parts EFI harness is connected to the battery on the dyno for 12-volt constant and ground. The dyno also has a provision for a switched ignition 12-volt, which we also connected to the harness.
In taking advantage of everything the engine dynamometer has to offer, one can extract horsepower and torque numbers, as well as exhaust gas temperatures, air and fuel consumption figures, water and oil flow, in and out water temperatures, and more. Plus, the engine dyno make it much easier to swap out major engine parts for testing, such as cams, heads, and headers.
The more high-strung your powerplant, the more you need an engine dyno to dial in the tuneup. Formula 1 teams even use engine dynos that can simulate the engine loads from a specific racetrack on a turn-by-turn or lap-by-lap basis. With this level of information, F1 teams can tailor engine specifications to each track, and also (attempt to) ensure reliability over a race season.
Since we plan to add a power...
Since we plan to add a power adder in the near future, we know we need more fuel volume than the stock fuel rails could offer. That being said, we ordered Trick Flow's TFX EFI fuel-rail kit. It comes with the rails, an adjustable regulator, fittings, and plenty of braided-steel fuel line. We also employed a set of 30-lb/hr fuel injectors.
In this engine test, we're not going to such an extreme, but we wanted to break in the engine on the Horsepower by Hedrick dynamometer, and then tune it for optimal power and torque. We'll follow this test next month with more dyno testing on a different induction system, and finally the aforementioned chassis dyno test so we can determine the exact loss through the drivetrain.
As you are able to extract more data from an engine dyno, it is a bit more laborious when it comes to bolting the powerplant up to the dyno. We spent several hours sorting out throttle actuation, header clearance, and other assorted issues.
We intended to use a stock A9L Ford EEC-IV computer to run the EFI system, and so we could do that on the engine dyno, we ordered one of Ford Racing Performance Parts' new M-12071-A50 electronic fuel-injection harnesses. It's designed with the crate motor guy in mind, who wants to run the factory electronics in his hotrod but doesn't want to modify an old, crusty harness. It has provisions for an electric fan, tachometer lead, fuel pump power, air conditioning switch, and more. The harness comes with great instructions on how to get your engine up and running in no time flat, and if you have a Fox-body or SN-95 Mustang, it will easily replace your factory harness as most of the harness extensions are designed with those chassis in mind.
Since we intend to run a lot...
Since we intend to run a lot of fuel-injected engines on the Horsepower By Hedrick dyno in the future, we called Aeromotive and ordered one of the company's A1000 electric fuel pumps, along with the associated fuel filters. The A1000 is more than capable of anything we intend on building/testing in the future. Should we need more fuel, Aeromotive offers it's Eliminator pump.
Tuning the EEC-IV box was handled by Tony Gonyon of HP Performance in Orange Park, Florida. Gonyon uses SCT software to write the program and burn it to one of SCT's computer chips. In addition to the tuning software, Gonyon also employs a SnEEC EEC-IV datalogger from Race Systems. It's a piece of hardware that is no longer produced, but it allows for optimal tuning of EEC-IV-controlled engines.
After entering the engine specifications into the dyno software, we cranked up the stroked small-block Ford and Mark Hedrick performed a break-in regiment, which loads and unloads the engine and alters the engine rpm. Having the dynamometer do this rather than having a human manually operate the dyno makes the process much more accurate and less tedious for the dyno operator. With the break-in complete, Hedrick made a few low-rpm, full-throttle pulls to creep up on the max rpm he had set at 5,500.
With the air/fuel ratio looking good, the oil temperature reading a steady 150 degrees, and the water temp at 140, our first 5,500-rpm pull netted 390.4 hp and 378.1 lb-ft of torque. This came with 29 degrees of total timing. For the next pull, we raised engine rpm to 6,000; peak power went to 398.3 and peak torque arrived at 378.3. Average power and torque was up thanks to a better air/fuel ratio. For the third pull, fuel was trimmed between 4,000 and 4,700 rpm, and ignition timing was increased to 31 degrees total. Peak power came in at 396.7 and the torque logged at a peak of 377.3 lb-ft.
We were thinking the tuneup was dialed in, so we made another pull to back the third run up. But this time at 5,600 rpm, power and torque dropped off by some 70 hp and 70 lb-ft! After a quick inspection, we tried again but the engine coughed at 3,800 rpm and we aborted the pull.
 Our 331 stroker is going into...  Our 331 stroker is going into Fox-body coupe that will see more strip than street action. To cut down on rotational drag and to make sure we had adequate water flow, we ordered this Moroso electric water pump (PN MOR-63585) from Summit Racing Equipment; It's capable of flowing 30-37 gpm. If you're using a stock water pump hose like we are, you'll need to order part number MOR-63543 for the billet, threaded hose outlet. Moroso also offers fittings for braided stainless steel lines, as well as smaller diameter hoses. |  We adjusted the Trick Flow...  We adjusted the Trick Flow fuel-pressure regulator to 40 psi. |  To connect our late-model...  To connect our late-model throttle body to the Superflow 901 engine dynamometer, we used this adjustable throttle cable, made by Lokar and sold through Summit Racing. Set aside the carb stud and the cable snaps on the throttle body just like the stocker. |
 For our induction, we mocked...  For our induction, we mocked up a 4-inch elbow from a cold-air kit, and attached it to a C&L Performance 76mm mass air meter with the sample tube calibrated for 30-lb/hr injectors. A K&N filter cleans the atmosphere up before it enters the engine. |  With the engine ready to run...  With the engine ready to run on the engine dyno, Mark Hedrick entered the engine's build information into the dyno software. |  With the software dialed in,...  With the software dialed in, we fired up our home-built 331 stroker. Horsepower By Hedrick's Mark Hedrick (far) ran a break-in program on the engine dyno to seat the piston rings and get the engine up to temperature. HP Performance Inc.'s Tony Gonyon (Near) connected the SnEEC datalogger to help build a base computer profile to which he will make more tuning changes off of. |