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Short-Block Stroker Engines - Popularity Content
If You're Looking For A 302-Based Stroker, We Break Down The Most Popular Short-Blocks On The Market
Paul's Automotive Engineering 347
Paul Faessler has been running his shop for 18 years now, and he is known and respected in vintage road racing, vintage restoration, performance engine building, and chassis setup. Getting into the late-model side of the Mustang market about five years ago, he has built several NMRA combinations and has a 347 short-block that is a strong seller.
One thing Paul wanted us to note here is that PAE is not a high-volume engine assembler. While the company can build a race car from scratch or bend up a custom rollcage, the small-volume, precision engine shop builds one engine at a time. All its engines are machined and built by one person, Steve "Scuba" Barker. And while a short-block can be shipped to any customer, the company prefers to assemble the complete engine, install it, and tune it in-house on its chassis dyno. A wise move, if you ask us.
The Paul's Automotive Engineering 347 takes life from a late-model 5.0 roller block that is chemically stripped, baked, and then shot-peened and Magnafluxed. Once the block is prepared, it is then machined. The cylinders are bored with two deck plates on board, and the mains are align-honed. Clearancing for the stroker connecting rods is, of course, completed at this stage, and the entire block is decked square. Further machining includes lifter-bore honing, deburring of oil passages, and all bolt holes tapped. The internals of the 347 include a cast-steel crank with a 3.400-inch stroke and 5.315-inch, forged I-beam connecting rods that are CNC profiled and fitted with ARP rod bolts. Forged pistons with dual standard and Twisted Wedge valve reliefs machined in are used, along with file-fit piston rings, for a price of $2,690.
Options on the 347 include a Trick Flow race girdle ($325), dished pistons ($70), forged 4340 steel crank and rods ($300), and either the B50 Sportsman block ($700) or the R302 race block ($1,500).
Probe Industries/Coast High Performance 347 Street Fighter
Probe Industries was founded in 1987 as a manufacturer of roller rocker arms for Ford and Chevy engines. Since then, Probe has become a manufacturer of shaft-mount rocker systems, billet oil-pump drives, steel main stud girdles, EFI intakes, and, of course, forged pistons in more than 50 configurations. The company can crank out 300 forged pistons an hour! Probe piston users include John Gullett's 2,100hp turbo Pro 5.0 car, John "Fireball" Urist's 1,900hp Outlaw car, and many others.
The company also manufactures stroker engine kits, short-blocks, long-blocks, and crate engines under the Coast High Performance name, offering crate engines from 306ci small-blocks to 572ci big-blocks. All CHP cranks are finished in-house and come in nodular iron (cast steel), 5140 forged steel, 4340 forged steel, or custom billet-steel options. All CHP stroker kits feature either Probe TrackMaster I-beam or H-beam connecting rods that are fully CNC-machined with ARP rod bolts or cap screws.
When it comes to the company's top seller, it is unquestionably the 347 Street Fighter short-block. George Klass of Probe Industries states that 20 of these babies fly off the shelf for every 1 they sell in another size! That's a lot of strokers out there. The 347 Street Fighter comes in a production 5.0 roller block and features 4.030-inch, forged Probe (naturally) pistons hung on 5.315-inch Probe connecting rods. These rods are bolted up to a 3.400-inch nodular crank. The entire assembly is professionally assembled in-house and can be ordered with numerous options including a main stud girdle, a forged crank, various cam and timing chain sets, and more. The standard 347 Street Fighter short-block will set you back $2,595.99 in dead presidents, or you can opt to let Probe build you a CHP long-block or crate engine.
Can I Get a Warranty with That?
When it comes to many driveline parts, the warranty (if there is any) is relegated to a single part. If your timing chain fails, the warranty will replace it, but that's it. What would you think about a 347 stroker, complete and ready to run, that has a two-year/24,000-mile warranty along with it? Sound interesting? We thought so too. The Blue Oval faithful that is Roush Performance has come up with a 347-based small-block that puts out 430 hp, includes quality materials, and has just such a warranty. Inside the Roush 347R is a forged-steel crankshaft, forged H-beam connecting rods, JE forged pistons, a Comp Cams custom-grind cam, a Cloyes double-roller timing chain, and 1.6:1 extruded aluminum roller rockers. This bounty of speed parts is then topped off by the new Roush 200 cylinder heads to complete the 347R base engine. This setup will run you $6,150 and is limited to a run of just 1,000 engines, all serialized. If you want to go with a complete turnkey, the "deluxe" engine package is what you need at $7,600. This upgrade will get you an Edelbrock Air Gap dual-plane manifold, a Holley 750-cfm carb, an MSD distributor and wires, and polished valve covers with engine serialization on them.