SpecsDisplacement: 454ci, bore x stroke- 4.250x4.000Carburetor: 850-cfm Holley HP or Race DemonIntake: Edelbrock Performer RPM Air Gap 2-R, PN 7562Heads: Stock rectangle port iron head, World Product Merlin 310cc rectangle port iron, PN 030030-1 with 2.2.50/1.880-inch valves and 119cc chamber, or Air Flow Research Magnum 305cc aluminum heads with 2.25/1.88-inch valves and 119cc chamber, complete, PN 2100Compression: 9.5:1 (slightly higher with aluminum heads)Camshaft: Comp Cams XS268 mechanical flat-tappet cam, 268/274 adv., 230/236 degrees @ 0.050, 0.553-/0.586-inch lift 110-degree lobe separationHeaders: Hooker 131/44- or 171/48-inch primaryExhaust: 3-inch exhaust with Flowmaster mufflers
Buick 455For the port-hole performance boys, we cornered Jim Burek of Performance Auto Engineering in El Paso, Texas, to get his ideas on building a 500hp Buick 455. Burek says that it's possible to achieve 500 hp with a set of stock iron heads, but that the TA Performance Stage 1 aluminum heads are capable of that feat right out of the box. Burek says that if you clean up the ports on a stock iron head just underneath the intake and exhaust valves you can make 500 hp. However, you may have to spend significant time in order to make that goal. The easier route is with the aluminum TA Performance Stage 1 aluminum casting.
For a camshaft, Burek likes the flat-tappet hydraulics for the Buick since they are much more affordable than the rollers. In order to make 500 hp with the better cylinder heads, you'll need a cam of around 236 degrees at 0.050-inch tappet lift with 248 or so on the exhaust side with a 110-degree lobe separation angle. This will create enough power to get the Buick going without spinning it very fast. On the exhaust side, Burek prefers the 171/48-inch headers and he prefers the X-pipe crossovers over the H-pipes, unless the engine is very mild.
The weak link with the Buick is its small area cam bearings that burn up easily. With a big cam and higher valve spring pressures, go with the back-grooved bearings that will prevent roasting the bearings. The other weakness is the block. Above 600 hp, the crank literally pushes the main webs right out of the block! The ultimate fix is a new iron block from Bulldog that will sell for around $3,600 but will offer over 1,000hp durability.
SpecsDisplacement: 455ci, bore x stroke-4.3125 x 3.90 inchesCarburetor: 750- to 850-cfm Speed DemonIntake: Edelbrock Performer, PN 2146Heads: TA Performance Stage 1 alum., 2.125/1.750-inch valvesCompression: 10:1Camshaft: 236/248 @ 0.050 flat tappet hyd. 0.500/0.520-inch liftHeaders: 171/48-inch full lengthExhaust: 3-inch w/X-pipe
Ford 460When it came time to determine a 500hp street package for the 460 Ford, we found an excellent combination in the Ford Racing catalog with the 460ci Super Cobra Jet crate engine. Ford rates this complete engine system at 500 hp and 495 lb-ft of torque. This is based on a custom-built, 0.030-over remanufactured block spinning all-new rotating pieces.
If you want to build your own, the combo is built around noted Ford engine-builder Jon Kaase's Super Cobra Jet aluminum heads that offer outstanding 330-cfm intake and 225-cfm exhaust flow numbers from a set of heads that use similar components to the previous Ford 429 Super Cobra Jet head. The valve angles have changed, so you may have to cut new notches in existing pistons. These heads will also require new pushrods and guideplates.
The cam for this package is a Ford Racing hydraulic flat-tappet with a relatively mild duration yet still cranking out over 0.550-inch lift. Induction duties are assigned to an Edelbrock Performer RPM 460 dual-plane and, like all the other engines, an 850-cfm carb will probably perform the best. On the exhaust side, a set of 131/44-inch headers may not look racy, but they will contribute to increased torque. They'll more likely fit better in the tight Ford engine compartment as well.