Project Boss 340's powerband tapped out just beyond this incredible reading of 8,002 rpm on the SuperFlow 902 engine dyno at Westech Performance Group. "That thing sounds like a Cup (NASCAR Sprint Cup) engine," said one observer. There won't be any roundy-rounding for our bullet. We plan on using Boss 340 for quarter-mile fun in a drag-only '90 hatchback LX 'Stang that's next in line as a 5.0 Mustang & Super Fords project car.
Horse Sense: Believe us when we tell you, nothing sounds sweeter than our project small-block Ford at full scream. Check out the video clip of Boss 340 at full spin. It's on our website right now, click here to see and hear for yourself, then drop us an email and tell us what you think.
This report on our project engine (Boss 340 Version 2.0) brings a close to the first stage of our effort to resurrect the Boss 302 Mustang theme. (Remember, a full-on drag-'Stang build is yet to come).
Boss 302 'Stangs ruled the roost on the streets and road courses back in the early '70s. The muscle-bound Ponies featured stout, high-winding small-block engines highlighted by high-lift, solid camshafts and big-port/big-valve, cast-iron cylinder heads that flowed like rivers. While all of the parts collectively make original Boss 302s worth a mint these days, the top-half pieces that we commonly refer to as heads/cam/intake on the original Boss 302s are the items that make the engines special.
With that in mind, we decided to build a new-era, Boss-style powerplant around the Boss 302 engine block from Ford Racing Performance Parts. With its 8.2-inch deck height, meaty 4.000-inch Siamese bores and screw-in core plugs, the new Boss block is quite similar to the original, but that's pretty much where the buck stops for similarities. We've definitely gone in a different, more-current direction when it comes to the rest of the engine's major components, especially its heads, camshafts, and intake manifolds.
With Version 1.0 of our Boss 340 completed and dyno-tested (see "Boss Power," Sept '08, p. 60) and its streetwise Edelbrock heads, Comp hydraulic-roller camshaft, and Wilson Manifolds intake all swapped for bigger, better-flowing, more race-oriented H/C/I hardware from Air Flow Dynamics, Comp, and Wilson (see "Top Loaded," p. 58, Nov '08), the stage is set for another round of performance evaluation on the SuperFlow engine dyno at Westech Performance Group in Mira Loma, California-and hopefully some eye-popping horsepower for our 340ci stroker.
The rest of this final engine story is best told through the following photos, captions, and dyno information. Once again, your tech editor and Westech dyno-specialists Ernie Mena and Eugene Walde spent a long, hot, challenging day (see Avoiding Near Disaster) in Westech's dyno cell to give Boss 340 absolute hell.
Although we escalated the Boss' redline far beyond that of any other project engine in our history, we also shot the engine with a few hits of nitrous oxide from Zex's new EFI Perimeter wet system. Not once did it flinch, become erratic, or completely fail during our test session.
Our canted-valve engine is a tremendous success. The new-school Boss is higher revving and far more powerful than its '70 namesake (in Version 1.0 and Version 2.0 trims), and with the availability of modern-day, Boss 302-specific parts such as intake manifolds and headers, it's no longer a fantasy engine for any 'Stangbanger out there who dares to be different and is up to the challenge of building one for their Pony.