The Fast As Cast cylinder...
The Fast As Cast cylinder heads offer up a 190cc intake runner volume, while the exhaust measures 66 cc.
Rounding out the induction side of the 331 is TFS' 5.0L R manifold, a BBK 75mm throttle body, and a TFS Trackmax Stage 2 camshaft to move the air in and out. Best of all is that you can order all of the parts from just two places, and with the same-day shipping from Competition Products and Summit Racing Equipment, you can have the combination built and shoehorned into your street machine in no time at all.
This month, we're bringing you the buildup of the engine; then we'll follow up with an engine dyno test, a chassis dyno test, and conclude with a quarter-mile drag test. You'll get to see what the parasitic loss is from crank to wheel horsepower, as well as how this stock-block stroke swap performs in a Fox-body Mustang at the track.
The combustion chamber volume...
The combustion chamber volume is still the standard Twisted Wedge 64cc, though the heart-shaped chamber does receive a CNC cut that is said to improve mid-lift numbers.
Cylinder-Head Flow Numbers
Tested on a 4.030-inch bore. Flowed at 28 inches on a Superflow SF-600Lift
| Lift | Intake | Exhaust |
| 0.100 | 71 | 57 |
| 0.200 | 145 | 115 |
| 0.300 | 214 | 150 |
| 0.400 | 257 | 187 |
| 0.500 | 268 | 194 |
| 0.600 | 273 | 197 |
The brain of our stroker engine...
The brain of our stroker engine revolves around a Trick Flow Trackmax Stage 2 hydraulic roller camshaft (PN TFS-51402001) and billet-steel timing chain and gears (TFS-51478520). Trickflow also provided us with a couple sets of pushrods to choose from after we confirmed the correct size using their pushrod length checker (TFS-9000). We ended up using a 6.700-inch pushrod (PN TFS-21406700).
While we could've gone with...
While we could've gone with the Trick Flow Track Heat-intake manifold, we opted for the higher RPM R-series after talking with Trick Flow. Part number TFS-51500003 is the silver powdercoated R manifold for the 5.0L Mustang with a 75mm throttle-body opening. You can also get the R manifold with a 90mm opening, in black or natural aluminum finishes. There's no provision for EGR. Topping off the cylinder heads are Trick Flow's silver valve covers (PN TFS 51400801).
Finishing off our stroker...
Finishing off our stroker buildup are these components from Competition Products. A Melling standard volume oil pump (PN M68), a PRW SFI 157-tooth flexplate (PN PRW1830204), and a Professional Products SFI 28-ounce harmonic damper with pulley spacer (PN PP90006, PP81007). Not shown is our 75mm throttle body from Brothers Performance.
The Trick Flow Trackmax Stage...
The Trick Flow Trackmax Stage 2 hydraulic roller camshaft features a split duration of 224/232 at 0.050, along with a split valve lift of 0.542 inch on the intake and 0.563 inch on the exhaust when using a 1.6:1 rocker arm. Lobe separation is 112 degrees. We installed the cam straight up.
Making sure the timing events...
Making sure the timing events happen when they're supposed to is a Trick Flow billet-steel timing set (PN TFS-51478520). This is a heavy-duty piece that has a three-position key way for running the camshaft straight up, or 4 degrees advanced or retarded.
Making sure our stroker engine...
Making sure our stroker engine maintains a fresh supply of clean oil is this Milodon 7-quart oil pan (PN 31125). It's designed for extreme street or strip applications and features oil-control baffles to subdue any unwanted oil movement. This keeps the oil supply right with the oil pickup tube where it needs to be. The pickup (PN 18380) can be used with Milodon's optional windage tray for even greater power gains.
Make sure you have the oil-pump...
Make sure you have the oil-pump shaft properly seated in the oil pump and block before tightening the oil pump itself. It doesn't hurt to upgrade to a high-performance shaft at this time either, but a stock one will work.
With the oil pump and pickup...
With the oil pump and pickup mounted, you'll need to check the pickup-to-pan clearance. Ideally, you want about a half-inch of space between the two. We used a suitably sized nut to simulate the desired distance and then put the pan on. If it hits, pull the pan off and tweak the pickup and check again. Do this until the nut no longer hits the pan.
The Milodon pan can be used...
The Milodon pan can be used with or without the factory support rails. It also features a leak-free screw in oil dipstick bung to work with Milodon's stainless steel dipstick, and offers front and rear sumps just like your stock pan.