Installing Edelbrock’s Performer Truck 5.0 Intake And BBK’s Twin Power Plus Series Throttle Body On A 5.0L 1991 BroncoPosted in How To: Engine on October 5, 2016
Ford truck engines back in the late ’80s through the mid-’90s were pretty sorry performers compared to today’s offerings, but they were competitive at the time. Base model F-150s and Broncos came stock with a 150hp 4.9L (300ci) I-6 through 1993, while Eddie Bauer editions came with the 185hp 5.0L (302ci) V-8. Those with a penchant for more horsepower opted for the 210hp 5.8L (351ci) V-8. By the end of Bronco production in 1996 the 302 was cranking out 205 ponies, only 5 hp behind the 351. We laugh at those numbers today.
Despite the low horsepower output, those early EFI Ford V-8s are good engines. They just couldn’t breathe well. That’s why Edelbrock came out with a 50-state-legal, direct replacement Performer Truck intakes for EGR-equipped 5.0L/5.8L EFI engines, which are claimed to add 35 hp on the top-end with a considerable gain in mid-range torque over the stock setup.
Getting that kind of bolt-on power boost from the stock 5.0L in our ’91 Bronco piqued our interest, as did the idea of replacing the stock 56mm twin-bore throttle body with BBK’s twin 61mm Power Plus Series throttle body, which could bring another 10 hp to the performance table.
Perfect Performance PairEdelbrock gets those power gains with a modular-designed CNC-port-matched aluminum upper and lower intake. The lower manifold is taller and its ports are rectangular instead of having the odd semi-curved shape of the factory intake. Those aspects, combined with porting to match the upper manifold, creates a considerable increase in airflow through the longer, equal-length Edelbrock runners.
The Edelbrock Performer Truck 5.0/5.8L EFI plenum is also larger with additional porting into the long runners. The design and machining of the two-part intake is all part of Edelbrock’s latest airflow design and CAD technology, which helps feed considerably more air into the heads than the stock intake. More air means the 5.0/5.8L can breathe a whole lot easier, which means more fuel can be added for more power. What’s nice about this bolt-on performance upgrade is the two-piece Performer Truck intake is a straight swap for the stock system, including all the components to keep the engine 50-state compliant for those who have to pass emissions testing.
The same is true for BBK’s twin 61mm Power Plus Series throttle body, which is CNC-machined from a 356 aluminum casting. The high-flow throttle body is built with double-sealed bearings, an O-ringed throttle shaft, and die-stamped throttle linkage so it exceeds OEM quality as the airflow gatekeeper for the intake. BBK’s throttle body is a bolt-for-bolt, smog-legal replacement for the stock unit, and it’s a perfect performance companion for the Edelbrock intake upgrade on an F-150/Bronco 5.0/5.8L engine.
Making The Power SwapSwapping out throttle bodies on an older Ford truck EFI takes about 30 minutes. Changing the intake takes the better part of a day. That was the scenario when we rolled a ’91 Bronco into Dunks Performance’s shop to have the mods done on its 5.0L engine.
What made the intake upgrade a real pain is these Fords had every smog-related hose, vacuum line, pipe, valve and switch known to man at the time attached to the engine, making it a mechanic’s nightmare. Once Dunk’s technician Scott Blanchard dug through the smog wiring and plumbing, the task at hand was the basic intake swap. Reassembly included new gaskets along with replacing almost every smog-related component on the 25-year-old engine.
When everything was back in place, we cranked up the engine, let it come up to operating temp, then turned it off. The Idle Air Bypass (IAB) connector was disconnected and the engine was restarted so the idle could be adjusted manually, all per BBK’s instructions. Then we plugged the IAB back in and went for a test drive.
The change in overall driving performance was quickly noticed. Our aged Eddie Bauer Bronco accelerated considerably stronger than it did before the Edelbrock/BBK upgrade with a slight whine from under the hood as the high-flow throttle body and intake sucked in volumes of fresh air. True to Edelbrock’s claims, the biggest performance boost seems to be in the 2,500-5,000 rpm range, where the added torque helps get the heavy Bronco rolling. It responds quicker to throttle too.
Looking to the future of this Bronco, we can imagine how sweet the Edelbrock/BBK combo would be if it were installed as part of a 5.0/5.8L rebuild running a mild cam and a freer-flowing performance exhaust system.