dyno pulls changing everything that we could think of, Jim was not happy with
the blow thru carb's ability to maintain a satisfactory A/F ratio across the
RPM range. While we were able to wring out over 500 RWHP at about 5500 RPM
with ~9 psi boost, the low speed off boost was really rich and the engine
would always go lean above some point as the boost continued to rise with
RPM (characteristic of a cent-supercharged engine). I have in the past been
able to get reasonable A/F control on a turbo engine with the carb, but turbos
can maintain a specified boost level. Centrifugal supercharged engines for
the most part never have a flat boost curve.
Jim wanted it fixed, and he know that EFI would cure all of his issues...but he needed an intake for his 460. He wasn't about to use a truck intake - so he made one....
Planning happened pretty quick, it didn't take long for Jim to figure out how he wanted this intake to look, he ran the ideas by Rory and I for a quick sanity check and started hogging the 6061. As can be seen in the photos above it was created with a 6" diameter tube for the plenum and 2.5" diameter runners feeding the 460 EFI cylinder heads.
Next up was the reducer needed attach the throttle body backer plate. This was created out of a piece of billet with allot of hogging time involved.
Now the intake was beginning to take shape. Holes were machined in the runner tubes and bungs welded in to support the 77lb/hr injectors that will be used to feed this ride.
Finally the last bit of welding by Jim brought everything together. The throttle body used was a 75mm piece from the late model LS1 chevy truck engines. It features an integrated idle air motor so that starting and idling of this older fairmont can now be absolutely perfect.
I was in charge of creating a custom harness for this fairmont from the EEC-IV harness that we removed from an 1988 5.0 cougar. Since this application would be running a distributor less ignition the factory harness was extensively modified to extract the full potential from the AEM engine controller that we were installing. Any additional wires that were no longer required were also removed. Since the fairmont did not have a hole in the firewall for the EEC harness, we cut one in the same location as all other EFI fox bodies to maintain an OEM appearance.
Since Jim's intake was designed to keep this big 460 hidden under a stock hood, a custom cam sensor was designed and built to squeeze into place. This custom piece utilizes a factory ford camshaft sensor to ensure OEM reliability.
The AEM controller found it's way under the factory dash onto a mounting pad previously used to retain an MSD 6AL ignition system. Thanks to the wasted spark direct ignition system that we are now installing there was no reason to retain the MSD.
A new engine harness was also required to be fabricated due to the additional length and width of the 460 when compared to the 302 that the harness was removed from.
Early Ford 4.6 modular coil packs are used to provide the jolt to the spark plugs. Jim built some mounting bosses on his custom valve covers to retain the coils.
On the left is the SEM 4 channel ignition driver that amplifies the AEM's signal to a high enough level to drive the coils. We also used one of our 12 tooth crankshaft wheels to ensure the AEM received the most accurate engine speed signal possible. The stability of the ignition system is nothing short of amazing when these components are combined with the AEM.
Here it's just about ready to run, still some little items to tidy up, but it's starting to look like a complete package. We ended up using a set of 4.6L modular spark plug wires and just modified the length to make them fit this one-off combination.
An AEM 2 channel wide band was the finishing touch to round our the engine management system. From these pictures you can see the super low profile of the intake manifold that allow the factor hood to be put back on the car, not to mention that Jim's new induction system weighs about 30 lbs less than the carb setup that it replaces.
Geez, sure looks sweet. eh?
And the answer to the question that everyone has -how does it run?.... With the carb setup and 9 psi boost (30 degrees total timing), the best pass was an 11.4 @ 120 MPH.
Now with the EFI and the same 9 psi the car has run a 10.46 @ 131 MPH with a modest 24 degrees total timing. We are changing to a smaller blower pulley over the winter as well as planning to get back on the dyno to optimize our timing map, I expect it to be an even stronger running street car next year.
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