Engine

 

With 1500 miles on it at the time of this writing (April, 1999), the 406 is now fully broken in and running very well.  The 280H cam and choke-less Quadrajet make it a little uncivilized, but it starts and drives fine.  It's got more power than the fat (275) tires and locker differential can handle and pulls hard all the way up to 5500 rpm (I haven't had the guts to go past that, since I keep hearing these horror stories about 400s vaporizing the instant they get past 5500).  Of course, there's that great "da-WHOOOOOOOOO" Q-Jet sound...

Block:  1971 4-bolt main 400 Chevrolet, bored .030" over for a total of 406 cubic inches.  I bought the block and crank fully-machined from a dirt-track racer near Sacramento.

Heads:  1965 3782461 "camel hump" castings, originally installed on a high-performance 327.  1.94" intake/1.50" exhaust valves.  New HD valves, Crane valve springs, Crane 1.5:1 ratio roller-tipped rocker arms.  3-angle valve job, hardened exhaust valve seats and full rebuild by Al Hubbard Machine Shop in Hayward, CA.

Pistons/Rods:  Forged TRW pistons (9.9:1 compression) with Speed-Pro moly rings.  Stock 400 rods rebuilt by Al Hubbard Machine Shop.  ARP rod bolts.

Camshaft:  Competition Cams 280H Magnum.  230º intake & exhaust duration @.050".  .480" intake & exhaust lift.  This cam sounds very mean, while (barely) giving the car enough vacuum to have power brakes.

Water Pump:  Milodon high-volume cast-iron pump, moving coolant through a Modine big-block radiator.

Fuel Pump:  Carter 120gph mechanical.

Intake:  Edelbrock Performer RPM Q-Jet (I know, that's an SP2P in the photo; I just used this engine-starving so-called gas-mileage intake to break the engine in with, since I had it sitting around at the time).

Flexplate/Damper:  Stock, balanced (along with the rods, pistons, etc.) by Ashland Grinding in Hayward, CA.

 

Carburetor:  Modified Quadrajet from 1970 500 cid Cadilliac Eldorado engine.  Dual cold-air induction system (see photos above) with air intakes on either side of the radiator.

Distributor:  1978 GM HEI, recurved with aftermarket weights & springs.

Exhaust:  Mystery Headers (from swap meet), 2-1/2" dual exhaust with crossover pipe, Flowmaster 2-chamber mufflers.  No tailpipes (tailpipes just slow you down!), just turndowns.  It's loud.