To the casual observer, it appears that Hollywood has found favor with a new type of TV format: the reality show. I would assume this is in contrast to a fabricated show with a script and paid actors. Within the car hobby, HPP is one of the few reality magazines. The pages are not filled with outlandish claims driven by advertising dollars or text that alludes to our editors having extraordinary success in getting Pontiacs to go fast and make big power with a simple turn of a screw and a few bolt-on parts. Our success is based on the fact that we live in the Pontiac world, and more often than not, it leads to the same level of frustration that you, our readers, endure. Technical stories and engine builds in some publications seem to go off without a hitch, while in contrast, we find every rusted bolt and cracked engine block. No, HPP is not the home of the hard-luck editors, we just report the truth as it appears without candy coating.
With that established, this article and thus, the author's assignment, was never supposed to exist. It's the direct byproduct of a series of events that will be all too familiar to anyone involved in this hobby.
How It All Began
As EFI has become more popular in recent years, our interest was piqued when HPP was contacted by Mass-Flo about its auto-tuning EFI system for PMD cars. Though Third- and Fourth-Generation Firebirds were factory-equipped with EFI, we are all well aware that the Chevy V-8 that was under the hood shared no DNA with a true Poncho powerplant. This left the question, would Pontiac engine technology respond as favorably to electronic engine controls as those from the other divisions of GM? To this cause, HPP technical contributor and '74 SD-455 Trans-Am owner Melvin Benzaquen volunteered his car as a testbed.
The original concept was to chassis-dyno the Firebird with the stock Rochester-carb and cast-iron-intake induction system and then switch over to the EFI and retest. This would provide an A-to-B comparison of not only the power and torque, but driveability and fuel economy as well. Finally, a Pontiac EFI story that would have relevance to a hobbyist with a pure-Pontiac engine. Simple, right?
For the chassis-dyno testing, we enlisted the help of Bob Ida of Ida Automotive in Morganville, New Jersey. Bob has a long history of tuning and drag racing, and over the years, has been a valuable asset to HPP, offering his knowledge and test equipment. The game plan was to dyno the SD at Ida, go back to Melvin's shop and install the EFI system, then go back to Ida for a retest. But first you need to know a little history about the engine in our subject T/A.
Based on Melvin's own admission, the car has been a hard-luck story. It has endured multiple "one-in-a-million" events but is still very much intact. During a restoration project, the engine was pulled and sent to a machine shop that claimed to wave the Pontiac flag. Almost one year later it was pronounced completely rebuilt and returned with a hefty price tag. Much to Melvin's dismay, it lasted 25 miles before a rod knock appeared and the cherry-picker hook was back over the intake manifold. The same engine builder took the Super Duty back and gladly made the necessary repairs in short order: six months instead of a year. Installed in the T/A and only driven on the street for a total of 250 miles, it sounded good and seemed to run well for a mostly stock rebuild. Then we went to the dyno.
When the T/A arrived at Ida...
When the T/A arrived at Ida Automotive, it looked as if it were 1974 all over again. Bob Ida uses Dynojet brand test equipment, which is inertia-based. The tires are on drums, and the dyno measures how quickly the drum accelerates and mathematically calculates horsepower and torque from that data. It is able to do that because the software knows exactly how much the dyno drum weighs. Though we experienced bad luck, an inertia-based dyno actually puts less stress on the driveline than a full-throttle pass at the dragstrip. The engine in the T/A was on borrowed time; the dyno test had nothing to do with its failure.
Melvin's Super Duty had been...
Melvin's Super Duty had been built to original specifications with the exception of a R/A-IV-spec cam and looked completely stock under the hood. The Q-Jet carburetor proved to be a little too rich on the top end, which gave away a few ponies. In that respect, the EFI might have an advantage in the carburetor's current tune. But since the engine is apart, Bob Wise, who is a Q-Jet magician, will blueprint the 33-year-old carburetor to correct the fueling issues. Not only will this improve the performance and driveability, it will make for a more accurate comparison to the Mass-Flo EFI system. It would not be proper to compare an untuned carburetor to a tuned EFI.
The cylinder-boring operation...
The cylinder-boring operation is accomplished with a machine called a boring bar. A tool bit attached to a rotating cutter-head enlarges the cylinder diameter to fit a new, larger piston. Most boring-bar machines attach to and reference off the block-deck surface. So if the deck isn't made perfect, the boring operation will be crooked as it was with our engine. A shop such as RaceKrafters that specializes in high-performance engine building has a machine that centers off the main bearing saddles, a more accurate fixturing location.