What we learn from both of these engines is what's possible from original equipment Ford castings, and it gives us a strong sense of what Ford engineers faced a half century ago. Though we have rare and desirable parts among these beasty 427s, imagine what they could do with better cylinder heads and induction. Ford's own 427 High Riser heads and induction would be a good start, though you'd lose torque on the low end.
The aftermarket offers a wealth of great cylinder heads and induction systems for the FE depending on your expectations and budget. Because these 427s had to be assembled as original-appearing FE mills utlizing factory castings, they suffer from the limitations of Medium Riser dimensions (2.18-/1.72-inch valves with 2.78x1.38-inch intake and 1.78x1.30-inch exhaust ports. With these heads, you get good low to mid-range torque, but not the full potential on the high end because they are basically a street/race head. The aluminum "XE" advantage isn't so much breathing, but instead great heat sink capability to where you can run a pinch more timing, higher compression, and a slightly leaner mixture depending upon what you get for a plug reading. This is where dyno time is money well spent before placing your FE between the shock towers. But that is another story. Check out the captions to see just how these two vintage V-8s faired in the dyno cell.
5 While we're not at liberty...
5 While we're not at liberty to tell you about the specs of the Comp Cams custom ground cam (you'll have to pry those out of the JGM folks), we can tell you that the moly coat goes on the lifter-to-lobe contact surfaces only. Engine assembly lube goes on the lifter bores and cam journals.
6 This is the FE's valley...
6 This is the FE's valley pan, which is designed to keep intake charge cooler by keeping hot oil away from the intake manifold. We've seen FE engines with and without these pans. It is suggested you use one in order to keep the manifold temperatures as low as possible.
7 This is an experimental...
7 This is an experimental magnesium dual-plane intake manifold void of part or casting numbers aside from firing order, which leaves a lot to the imagination. We've learned from a number of sources that Shelby used these on competition Cobras. The problem with magnesium is corrosion and distortion. JGM had to use an epoxy resin to repair damaged areas including one coolant leak.
Two FEs--One Polygraph Room
This was an opportunity to dress a 427 up in its original clothing void of special modifications--basically Ford's legendary Cobra FE 427 as it was in the mid-1960s when it powered the world's fastest production automobile. We wound up with 510 hp and 503 lb-ft of torque. This is what JGM got from a basically stock 427 FE with rare metal on top. Horsepower and torque numbers aren't much different than you would have seen in 1966, and the gains aren't all that significant with the aluminum heads and magnesium intake. Aluminum heads allow us to run more timing and less jetting in an effort to gain power. Further gains could have been achieved with a more aggressive roller mechanical camshaft, larger carburetor, and richer jetting. Jim and Jeff followed instinct and went with what they knew works. Here are some of the more significant pieces JGM specified for this circa '66 427.
|JE custom forged pistons with race ring set||(No Part Numbers)|
|ARP connecting rod bolts||200-6001|
|Fel-Pro gaskets and seals throughout||
|Comp Cams flat tappet mechanical camshaft custom grind||33-000-5|
|Comp Cams valvesprings||972-16|
|Comp Cams lifters||810-16|
|Sealed power rocker shaft||RS-621|
|Pro-Gear high-performance timing set||PG4108|
|Melling high-volume oil pump||M-57HV|
|ARP oil pump shaft||154-7902|
|AMK Products cylinder head bolt kit||F-1771|
|AMK Products engine bolt kit||660-427HP|
|C5AE-H experimental aluminum heads||2.18/1.72-inch intake/exhaust|
|C6AE-J 427 side-oiler block with SOHC drain holes||
|Magnesium dual-plane medium riser induction||No Part Number|
|"XE132391" steel crankshaft with Welsh oil galley plugs and C-clips|
|C6AE-E cap-screw connecting rods with ARP bolts||also 428 SCJ|
8a We've found through experience...
8a We've found through experience that Fel-Pro Print-O-Seal intake manifold and head gaskets work well on just about any engine type. This revolutionary gasket design seals intake ports and cooling passages very well without sealer.
8b If you feel you must use...
8b If you feel you must use sealer, opt for Permatex's The Right Stuff and keep your application hair thin around cooling passages only.
9a If you think torquing...
9a If you think torquing iron and aluminum intake manifolds is tricky, try magnesium, which requires extraordinary caution.
9b Torque should be a properly...
9b Torque should be a properly sequenced 25 ft-lbs beginning in the center and working outward. Though very tedious, this is something you do in one-third incremental torque values.
10 Though you're probably...
10 Though you're probably never going to encounter a magnesium manifold, the only way corrosion damage can be repaired is a good industrial grade epoxy resin. Magnesium can't be welded unless you really enjoy out-of-control fire. Once magnesium begins to burn, it can't be stopped.
11 We're running the old...
11 We're running the old valvesprings for break-in only. During break-in at 2,500 rpm for the first 30 minutes, we work-harden the cam lobes. Stiff valvesprings can wipe the cam.