509 Aluminum Big Block Engine Build - Retro Hilborn Fuel Injection Unit

The rocker pedestal boss on the head is machined for the dowel to locate the pedestal, which is secured by the rocker bolt.
The rocker pedestal boss on the head is machined for the dowel to locate the pedestal, whi
Note the funky angles of the rocker arms. Walden's -690 heads are based on the factory 425-horse street heads, but have had improvements made to the valve location and ports, influenced by the factory Z11 heads.
Note the funky angles of the rocker arms. Walden's -690 heads are based on the factory 425
Lamar designed lifter bodies with offset pushrod cups to gain extra clearance and improve pushrod angles.
Lamar designed lifter bodies with offset pushrod cups to gain extra clearance and improve

Walden's billet timing chain cover, with integral cam button, was installed. Big-block Chevy and 409 timing covers aren't interchangeable, but they are on the new aluminum block, opening up the possibilities for much easier-to-find BBC covers, and readily-available belt drives and crank-trigger ignition systems.
Walden's billet timing chain cover, with integral cam button, was installed. Big-block Che
Nothing looks like a 409 water pump, and keeping that unique piece was a prerequisite for the aluminum block, though a standard BBC piece would have been less work in the design phase. Walden has had his own aluminum pumps cast for years, with a reinforced bearing housing.
Nothing looks like a 409 water pump, and keeping that unique piece was a prerequisite for
After the aluminum 509 block was announced, Hilborn contacted Lamar and wanted to do a retro fuel injection unit. The Hilborn unit has bosses for mechanical or electronic fuel injection, and three sizes of butterflies. This is the first, and uses 2.5-inch butterflies, 60-pound injectors, and is controlled by a FAST computer system and distributor. The 3-piece intake (injector banks and a separate valley cover) was powder coated black.
After the aluminum 509 block was announced, Hilborn contacted Lamar and wanted to do a ret

Finishing the prototype engine is a new serpentine belt-drive system. Unlike other systems on the market, this can be tailored to mount any combination of power steering, A/C, or dual alternators, without a bunch of additional "dummy" idlers. Lamar reversed the water pump to work with these. Note the humped spokes in the pulleys, inspired by the valve cover's shape. This set-up was hours old when we shot it, and wasn't completely finished.
Finishing the prototype engine is a new serpentine belt-drive system. Unlike other systems

RPM - HP - TQ
3,300 - 251 - 533 / 3,400 - 262 - 545 / 3,500 - 273 - 552
3,600 - 273 - 532 / 3,700 - 281 - 531 / 3,800 - 293 - 532
3,900 - 304 - 534 / 4,000 - 314 - 539 / 4,100 - 330 - 550
4,200 - 342 - 556 / 4,300 - 366 - 571 / 4,400 - 384 - 578
4,500 - 411 - 591 / 4,600 - 439 - 609 / 4,700 - 450 - 618
4,800 - 487 - 629 / 4,900 - 486 - 639 / 5,000 - 496 - 643
5,100 - 506 - 648 / 5,200 - 527 - 655 / 5,300 - 543 - 659
5,400 - 555 - 662 / 5,500 - 573 - 667 / 5,600 - 584 - 665
5,700 - 589 - 660 / 5,800 - 603 - 660 / 5,900 - 619 - 660
6,000 - 627 - 656 / 6,100 - 636 - 653 / 6,200 - 642 - 649
6,300 - 643 - 634 / 6,400 - 648 - 630 / 6,500 - 655 - 628

SOURCES
World Products 51 Trade Zone Court Ronkonkoma NY 11779 631-981-1918 www.worldcastings.com	Lamar Walden Automotive 6 Steve Drive #B Doraville GA 30340 770-449-0315 www.lamarwaldenautomotive.com