Do you remember when displacements above 400 ci were considered big-blocks? do you remember the overwhelming aura surrounding a big-brute Cobra Jet Mach 1 or Torino? When it comes to making power, there really is no replacement for displacement. In our quest to go faster, we've tried to shoehorn more displacement into big-blocks, arriving at nearly 600 ci with some of them. We've done the same thing with small-blocks, pumping as many as 429 ci into a 351W-based block. Aftermarket small-blocks allow even greater numbers, pushing 460 ci. The bonus here is mega-cubes without the penalty of weight. Translated-that's lots of available power from a lightweight package.
So why is it we don't just build a lot of big-inch small-blocks and throw away those old rotund big-blocks. Why do we even mess with an FE- or 385-series big-block anymore when we can stuff a boatload of displacement into something the size of a 351W? We asked Coast High Performance (CHP) this question.
Chris Huff of CHP suggested we build two engines using a nice combination of Coast High Performance and Edelbrock parts, and throw them on one of Vic's dynos. Two engines of similar displacement-a 351W bored and stroked to 427 ci, and a 390ci FE bored and stroked to 428 ci. Which of these engines will make more power and how? Let's find out.
Coast High Performance prides itself on building powerful Ford small-blocks. Truth is, CHP pioneered the modern stroker small-blocks-the legendary 347 and 427ci stroker small-blocks that have stood the world of drag racing on its ear over the past decade. Coast calls its line-up of powerful strokers the Street Fighter and Pro Street Fighter series. These engines were born for the lightweight, FOX-body Mustang crowd, but they're at home in any Ford engine compartment. As the Street Fighter name implies, these potent sticks of dynamite in small packages make all kinds of power right out of the box. Mix in nitrous or a healthy supercharger and numbers become staggering.
So how do we get 427 ci (or 8 liters) into a block designed for 351 ci? First, we increase the bore size a pinch or two. Next, we lay in a crankshaft with a greater rod journal throw, which really pumps up the displacement. Big-cube displacement comes from running the piston deeper into the cylinder bore for greater amounts of air and fuel. With that deep lungful, we also get the mechanical advantage that comes from greater leverage. The longer stroke gives our 351W greater leverage, just like we learned in high school physics class. With a long enough lever, you can move the world.
So what does shoehorning 427 ci into a Windsor block do for performance? It means as much as 500 hp and more than 500 lb-ft of torque when the go pedal is mashed. Depending on how you build your CHP 427W, it can be anything you want it to be. Pick the right camshaft, cylinder heads, and induction for trailer towing with your vintage Ford F-100 truck or Ranch Wagon. Opt for a more radical camshaft and deep-breathing heads for spine-decalcifying performance out of the traffic light. The beauty of a 427W Street Fighter is the versatility. You can build it anyway you desire and without the weight penalty of a big-block.
The 351W block sports five...
The 351W block sports five main bearings, just like the FE block. The advantage here is less weight because there is less iron. The FE's main bearing saddles wrap around the crank for better support.
The CHP 427 Street Fighter is available in two overbores: .030- and .060-inch oversize. We strongly suggest going with the standard 4.000-inch or 4.030-inch bore sizes for best results. Even though the 4.060-inch bore is available, we discourage this selection in the interest of solid engine integrity with a 351W small-block.
What Did It Do?
|Bore: 4.040 inch|
|Stroke: 4.170 inch|
|Facts:Cast Steel CrankshaftProbe SRS Forged PistonsOptional Dished & Blower PistonsCHP Beam Forged Steel Connecting RodsFlat Tappet High-Performance Hydraulic CamshaftEdelbrock Victor Jr. Induction System & HeadsEdelbrock 750-cfm CarburetorMSD Ignition SystemHigh-Volume Oil PumpDynamic BalancedVintage or Late-Model Ford Applications|
|Horsepower Tip: a roller camshaft would have pushed the 427W over 500 hp with over 500 lb-ft. of torque.|
The 351W's mains need the...
The 351W's mains need the lightweight support of a stud girdle if you are going to spin it tight. To accommodate the 427 stroker bottom end, Coast High Performance cuts some iron out of the cylinder skirts to clear the connecting rod bolts.
These bores are 4.060-inc...
These bores are 4.060-inches.
Pumping up the displacement...
Pumping up the displacement comes from a custom-ground cast-steel crankshaft, and forged rods and pistons.
Because we are increasing...
Because we are increasing compression height with greater stroke, we have to dish the piston to control compression.
Camshaft and valvetrain components...
Camshaft and valvetrain components come right off the shelf at Coast High Performance and Probe Industries. This flat tappet hydraulic bumpstick is .520"/.544" 234/244 112 LSA with a bit of a bump at idle. Open the throttle and watch out!
These are CNC-ported heads...
These are CNC-ported heads with 2.05/1.60-inch valves and 60cc chambers available from Coast High Performance.
On top, the 427W is equipped...
On top, the 427W is equipped with Edelbrock Victor Jr. Stage 1 cylinder heads and induction, including an Edelbrock 750-cfm carburetor.
All CHP small-block Ford builds...
All CHP small-block Ford builds get screw-in freeze plugs at these oil galleys. The factory used pressed-in plugs. Why chance it?
Whenever possible, opt for...
Whenever possible, opt for a late-model 351W block with the one-piece rear main seal.
Plenty of assembly lube at...
Plenty of assembly lube at the main bearings and on the cylinder walls ensure lubrication during start-up.
We like the 351W huge main...
We like the 351W huge main bearings, which make the Windsor a great candidate for displacement.
To keep this comparison fair,...
To keep this comparison fair, we're giving the 427W a flat-tappet hydraulic camshaft.
Anatomy of an FE stroker for...
Anatomy of an FE stroker for the new millennium: a cast-steel crank, H-beam connecting rods, and forged dish pistons. This assembly is dynamic balanced for smoothness. Slugs are custom Probe pieces.
Our foundation is a '61 vintage...
Our foundation is a '61 vintage 390 block that has been bored .060-inch oversize.
The nice thing about an old...
The nice thing about an old FE block is the support system-five main bearings in a Y-block configuration. Lots of support going on here. This makes it stronger than the small-block.
Good old-fashioned hydraulic...
Good old-fashioned hydraulic flat tappet tech here. Edelbrock's Performer camshaft, .572L/236D/108LS, will deliver an ever-so-slight lumpy idle with good, crisp throttle response.
As you might expect with any...
As you might expect with any professional engine build, ARP fasteners are the only way to go when it comes to keeping an engine glued together. Both big-cube powerplants are held together with ARP.
This is a Scat cast steel...
This is a Scat cast steel crankshaft with a 3.98-inch stroke. What may surprise you is the main bearing size. The FE has smaller main bearing journals than the 351W.
A dual-roller timing set is...
A dual-roller timing set is fitted to the FE big-block for solid reliability at all rpm ranges.
The bottom end and camshaft...
The bottom end and camshaft are dialed-in as shown to determine integrity. Here, we are looking at camshaft specs and piston position mostly. We did this on number one bore, but it's a good idea to do it on all eight.
A high-volume oil pump feeds...
A high-volume oil pump feeds the FE's healthy oiling system. The FE-series big-block was blessed with a good oiling system to begin with. When Ford went racing, it learned the hard way where this system needed tuning. For street engines, it is more than adequate.
Doing It FE - The Old Gun SlingerWhen we think about the 427/428ci Windsor small-blocks, it is easy to define them as cocky, young upstarts ready to take on the old man. What the old man has on his side is wisdom and size. In the world of Ford, the old man couldn't be anything less than a big-cube FE-series big-block-the mill that won LeMans and kicked Ferrar's ass 40 years ago. It also spanked more than its share of GM and Chrysler musclecars in NHRA competition.
So why an FE instead of a Windsor? The answer is simple-we like the massive demeanor of a vintage Ford big-block. It's like an elephant in the living room; you just can't ignore this beast. Aside from size, there is no ignoring the amount of momentum that exists across five main journals in the Y-block design.
That's a lot of crankshaft married to larger connecting rods. It is going to make a lot of torque.
We're about to show you why there really is a difference between small-blocks and big-blocks with identical displacements. You have to think of the big-inch small-block as the lean, but powerful tough guy down the block. By the same token, you have to think of the FE big-block as rotund as a Greyhound bus, but every bit the old football player who can still hold his own against the bad guys.
CHP has topped the FE with...
CHP has topped the FE with an Edelbrock Performer induction system, cylinder heads, and an 800-cfm carburetor. These are good, healthy street heads with 2.09/1.66-inch valves and 72cc chambers. With some good port work, they work well. CHP does nice CNC-porting on these heads.
The FE big-block has the weight and moment advantage here. Translated-more torque from a huge crankshaft. Lots of kinetic energy going on here.
What Did It Do?
|Bore: 4.113 inch|
|Stroke: 3.980 inch|
|Facts:Custom Cast Steel CrankshaftProbe Forged Custom PistonsH-Beam Forged Steel Connecting RodsEdelbrock Performer Flat TappetHydraulic High-Performance CamshaftHigh-Volume Oil PumpDual-Roller Timing ChainEdelbrock Performer RPM Induction & Cylinder HeadsEdelbrock 800-cfm CarburetorMSD Ignition System|
It Really Is All About Size Small-block versus big-block. Which is better? It depends on how you measure "better." The small-block has the advantage of less weight. But the big-block has the momentum and leverage advantage in a larger crank with larger counterweights and longer connecting rods. Each engine makes power in its own way. The small-block tends to make more horsepower. The big-block tends to make more torque. This doesn't always mean this will be the result on the dyno.
We're going to fire the mixture...
We're going to fire the mixture with an MSD billet distributor and wires.
Fel-Pro gaskets are an industry...
Fel-Pro gaskets are an industry standard. Coast High Performance uses Fel-Pro on all of its engine packages.
Small-block and big-block...
Small-block and big-block cranks side by side. The 427W crank on the left yields nearly the same stroke as the 428 FE crank on the right. The FE advantage is in those huge counterweights that maintain momentum. The 427W's longer stroke sports the mechanical advantage when the piston begins to lean on the rod.
Let's look at the pistons...
Let's look at the pistons and rods. The FE big-block rod/piston combo on the right has the size advantage-better rod ratio.