Jim Smart
January 1, 2001
Photos By: Mustang Monthly Archives

Making more power boils down to how much energy we can glean from the compressed air/fuel mix. The more volume we can huff into the chamber, the more power our engine is going to produce. We compress more air and fuel with a supercharger, a larger carburetor or throttle body, bigger valves, or a greater amount of displacement. Greater displacement is likely the cheapest way to pull power from a given block–and–cylinder head combination.

Strokers have always been the swiftest path to displacement and power. And engine builders have been building strokers for ages. Take the 289/302 engine block, for example. Did you know that you can infuse up to 355 ci into this block? The nimble 351W can be pumped up to 429 ci. Just imagine, big-block power from a small-block. Larger mills, such as the 429ci big-block, can be stroked up to more than 500 ci—talk about power!

The groovy thing about a stroker is what you don't see externally. This is a 302 small-block. Unless someone told you, would you know it was a stroker-displacing 347 ci? It sounds like a 302. It looks like a 302. Just imagine the fun you could have with the invisible displacement advantage.

When you’re rebuilding a Mustang’s V-8 engine, you can increase the displacement with a stroker kit without anyone being the wiser. What’s more, stroker kits don’t cost any more to build. Add to this their convenience and you’re ready to build in cubes. Stroker kits are available already machined and ready for assembly. In some cases, all you have to do is prep the block, which can be accomplished through your local machine shop. In fact, we suggest that your machine shop handle the entire build-up, checking all tolerances before complete assembly.

What Is a Stroker?
As its name implies, a stroker is where we increase engine displacement by increasing piston stroke. When we increase stroke, we take the piston deeper in the cylinder bore, which increases displacement. The longer the stroke, the greater the fuel/air charge. Because mechanical advantage or leverage comes with stroke, torque does too. Think of stroke as you would using a breaker bar instead of a ratchet to remove a stubborn bolt. The longer the lever--or stroke--the greater the mechanical advantage.

We can stroke an engine in a number of ways. One way is to offset-grind the crankshaft rod journals, adding some meat at the top of the rod journal, then grinding the journal true again. This adds stroke, even if it's just 0.020 inch. This might not seem like much, but it can add up to significant displacement increases. Remember, Ford stroked the 289 0.013 inch to achieve 302 ci.

Another way to achieve stroke is to machine a larger crankshaft down to fit a smaller block. The 347ci stroker is designed this way. We take a 351W crankshaft, machine the main journals and counterweights to fit the 289/302 block, and we end up with a 347ci stroker. The same is true for the 408ci stroker from a 351W block. A 400M crankshaft is machined down to fit the 351W block. Stroker kits often go even further, using Chrysler or Chevrolet connecting rods to achieve stroke. Piston wrist-pin height is another means, which calls for the use of custom pistons.

Stroker kits make obtaining displacement a no-brainer, because all you provide is the block--and in many cases, the manufacturer provides the already machined block, making short work of displacement.

Step By Step

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289/302 Small-Block Stroker Kits
Stroker kits for the 289/302 are plentiful, ranging from low-buck budget to the high-priced spreads for racing applications. Your mission and your budget directly determine what kit is best for you. Resist the temptation to order the greatest displacement available for your block, because it may not be appropriate. If you're going to push the engine, opt for better rods, pistons, and a steel crank. Weekend racers and cruisers will live fine with a cast crank and factory-style I-beam connecting rods.

Ford Performance Solutions 317 ci

  • 302 block
  • 3.100-inch stroke
  • High-nodular-iron early 302 crankshaft
  • Eagle 5.400-inch connecting rods
  • Ross ultralite forged pistons
  • Clevite 77 main and rod bearings
  • Childs & Albert piston rings
  • Kit price: Starting at less than $1,800

Nowak Racing Engines 327 ci

  • 302 block
  • 3.200-inch stroke
  • Australian 302 nodular-iron crankshaft
  • Eagle 5.400-inch connecting rods
  • Nowak forged-aluminum pistons
  • Michigan 77 main and rod bearings
  • Childs & Albert or Speed-Pro piston rings
  • Kit price: Starting at less than $2,500

Coast High Performance 331 ci

  • 302 block
  • 3.235-inch stroke
  • Early 302 nodular-iron crankshaft
  • English Ford 1,600cc engine
  • 5.200-inch connecting rods
  • Probe forged-aluminum pistons
  • Clevite 77 main and rod bearings
  • Kit price: Starting at less than $2,000

Ford Racing Technology 347 ci

  • 302 block
  • 3.400-inch stroke
  • Cast-steel crankshaft
  • 4340 steel 5.315-inch connecting rods
  • Wiseco forged-aluminum flat-top pistons
  • Clevite 77 main and rod bearings
  • Childs & Albert piston rings
  • Kit price: Starting at less than $2,000

Ford Performance Solutions 347 ci

  • 302 block
  • 3.400-inch stroke
  • High-nodular 351C crankshaft
  • Eagle 5.400-inch H-beam rods
  • Ross ultralite forged-aluminum pistons
  • Clevite 77 main and rod bearings
  • Childs & Albert piston rings
  • Kit price: Starting at less than $2,500

Coast High Performance 347 ci

  • 302 block
  • 3.400-inch stroke
  • Cast-steel crankshaft
  • Blue Thunder 5.315-inch I-beam rods
  • Probe forged-aluminum pistons
  • Clevite 77 main and rod bearings
  • Childs & Albert piston rings
  • Kit price: Starting at less than $2,000

Speed-O-Motive 357ci

  • 302 block
  • 3.500-inch stroke
  • 351C nodular-iron crankshaft
  • Eagle 5.400-inch connecting rods
  • Ross custom-forged pistons
  • Clevite 77 main and rod bearings
  • Speed-Pro piston rings
  • Kit price: Starting at less than $2,500

351W Stroker Kits
It's nearly impossible for us to believe that you can almost stuff a 430 ci into a 351 Windsor small-block. Just imagine, big-block power from an engine the size and weight of a 351W. It gets us excited too. You can keep your '69 Mach 1 looking dead stock outside, while breathing big-block cubes inside. Just imagine the bewilderment your buddy in the Camaro is going to feel when you spank his 350ci RS/SS, while going through the traps Saturday night. This is the beauty of a stealthy stroker.

Nowak Racing Engines 377 ci

  • 351W block
  • 3.680-inch stroke
  • 351W nodular-iron crankshaft/offset ground
  • Chrysler I-beam 6.125-inch connecting rods
  • Nowak forged-aluminum pistons
  • Michigan 77 main and rod bearings
  • Childs & Albert or Speed-Pro moly piston rings
  • Kit price: Starting at less than $1,500

Coast High Performance 408 ci

  • 351W block
  • 4.000-inch stroke
  • Nodular-iron 400M crankshaft
  • Eagle 6.200-inch connecting rods
  • Probe custom-forged pistons
  • Clevite 77 main and rod bearings
  • Childs & Albert piston rings
  • Kit price: Starting at less than $2,200

Ford Performance Solutions 408 ci

  • 351W block
  • 4.000-inch stroke
  • High-nodular 400M crankshaft
  • Pro H-beam 6.125-inch connecting rods
  • Ross ultralite forged pistons
  • Clevite 77 main and rod bearings
  • Kit price: Starting at less than $1,800

Ford Performance Solutions 426 ci

  • 351W block
  • 4.170-inch stroke
  • High-nodular 400M crankshaft
  • Pro H-beam 6.125-inch connecting rods
  • Ross ultralite forged pistons
  • Clevite 77 main and rod bearings
  • Kit price: Starting at less than $1,800

Speed-O-Motive 426 ci

  • 351W block
  • 4.170-inch stroke
  • Nodular-iron 400M crankshaft
  • Eagle 6.125-inch connecting rods
  • Ross forged-aluminum pistons
  • Clevite 77 main and rod bearings
  • Speed-Pro piston rings
  • Kit price: Starting at less than $2,000

Performance Automotive Warehouse (PAW) 427 ci

  • 351W block
  • 4.125-inch stroke
  • 400M crankshaft
  • I-beam forged-steel connecting rods
  • Clevite 77 main and rod bearings
  • Sealed power moly piston rings
  • Kit price: Starting at less than $2,500

385-SERIES BIG-BLOCK Strokers
If your objective is ground-pounding twist and shout, there's nothing quite like a big bore and long stroke to get the job done. The 385-series engine family can handle upward of 550 ci--given your budget, a custom crank, rods, and pistons. Because we understand the importance of budget for your mild-mannered street stormer, we're going to focus on affordable stroker performance.

Coast High Performance 501 ci

  • 429/460 block
  • 4.160-inch stroke
  • 460 nodular-iron crankshaft
  • Eagle 6.800-inch connecting rods
  • Probe forged-aluminum pistons
  • Clevite 77 main and rod bearings
  • Kit price: Starting at less than $2,500

What About the FE?
If your Mustang has an FE-series 390 or 428 Cobra Jet, you're likely wondering what's available to pump displacement into these classic big-blocks' time that the aftermarket seems to have forgotten. You can stroke a 390 High Performance using a 428 crankshaft to achieve 410 ci, just as Mercury did in 1966-'67. If your dear and late Uncle Ned left you boatloads of cash when he punched out recently, you can stroke the 427 block using a 428 crank to round up to 454 ci.

Because most FE blocks have experienced at least one rebuild in their service life, you can count on at least one overbore to 0.030 inch oversize. The FE big-blocks--except for the 427--will accept generous overbores up to 0.060-inch oversize. Because the 427 reaches the limits of the FE block with a 4.23-inch cylinder bore, the most they will accept is 0.020-0.030-inch oversize without flash floods. By the way, the 428 crank can be offset-ground to achieve a modest stroke increase.