Just throw us in the looney bin. In the realm of cubic inches, 500 is a figure reserved for tall-deck Rat motors and Cadillacs. Any notion of ascertaining that level of displacement out of a small-block-or even most big-blocks-is pure crazy talk.

Sanity and common sense aside, we're here to say that it can be done. In fact, it's already been done and here's the kicker: It's been done with a production LS2 block. The motor in question, built by the School of Automotive Machinists in Houston, kicks out 717 hp and 630 lb-ft on pump gas with a dinky 248/254 at 0.050 inch hydraulic cam. The best news is that this isn't some custom one-off build. Anyone can now assemble a 500ci LS-series motor using off-the-shelf parts.

The mastermind who makes it all possible is ERL Performance, best known for its handiwork in the import drag racing scene. In a high-boost world where displacement is at a premium, ERL has perfected the art of making tiny four-cylinder motors a bit less tiny with its innovate deck plates, essentially a slug of billet aluminum sandwiched between the block's deck surface and cylinder head. The added thickness affords a taller deck height and hence a longer stroke and more cubic inches. While it sounds more like an elaborate IED (improvised explosive device) than a viable engine technology, ERL's deck plate system has been proven time and again under the most grueling conditions. We're talking sub-150ci boosted four-bangers pushing close to 1,000 hp on production blocks.

Aware of ERL's credentials, engine builder extraordinaire and LS1 guru Judson Massingill of SAM asked the obvious question while at an industry trade show. "I saw that ERL was doing these amazing things with Imports and suggested that they should apply this same technology to V-8s," he recollects. "At the time, people were starting to really push the limits of the LS1 architecture, and a common problem with stroker motors was scuffing up the piston skirts as a result of pulling them too far out the bottom of the bores. I pointed out that since the cam is positioned so high in the LS2 block and because it has a 4.000-inch bore, they could get some serious displacement out of it with one of their deck plates. I really can't take any of the credit, because all I did was have one conversation with them and they took care of the rest. ERL's finished product is honestly some of the most beautiful machine work I have ever seen."

By increasing the LS2's deck height from 9.240 to 10.200 inches, ERL's Super Deck II block can swallow up a 4.500-inch stroke. Combined with a 4.202-inch bore, the result is 500 delicious cubes. Considering the Gen IV's bore spacing of 4.400 inches, that much bore may seem to push the envelope of strength on paper, but ERL has done its homework. "We use a Darton ductile iron sleeve, which is three times stronger than stock," explains Sean Ragains of ERL. "Also, our deck plate is designed so that when you torque down the head bolts, they apply clamping pressure right at the top of the cylinder sleeves instead of the deck surface. This directs pressure to a smaller surface area, which results in greater clamping force. The truss design of our deck plate also transmits loads below the deck surface and between the cylinder bores. The result of all this is an extremely strong block with excellent head gasket seal."

So just how much power can it handle? On a 200hp hit of spray, SAM's 500 cranked out 923 hp and 906 lb-ft on the dyno. Furthermore, while ERL suggests backing down to a 4.1250-inch bore on boosted or heavy nitrous applications, its customers are pushing out 1,500 hp in supercharged motors and 1,700 hp with turbos. That's staggering, to say the least, but there's more to ERL's setup than a deck plate, as we'll outline in this story. So enough babbling already and on with the build!

Quick Notes
The Build

A 500ci LS motor!

Bottom Line
717 hp and 630 lb-ft on pump gas

Price (short-block only)
$14,900

Get Your Own 500
If the prospect of 500 all-aluminum rippling cubes has already made you bash open your piggy bank, here's the skinny on how to get an ERL setup in your car. The Super Deck II system is sold as a turnkey short-block assembly for $14,900. If you provide your own LS2 core, ERL will knock $1,000 off the total. That price includes an ERL block, a Callies crankshaft, full internal balancing, Wiseco pistons, rings, bearings, billet main caps, main studs, bushed lifter bores, intake manifold adapter plates, longer head studs and pushrods, and a cam custom-ground to your application. All you need to add are cylinder heads, an intake manifold, and an oil pan. ERL offers bore sizes from 4.000 to 4.200 inches and will tailor compression to whatever ratio you chose.

BUILDSHEET
Block ERL Tall-Deck LS2
Bore 4.202
Stroke 4.500
Displacement 500 ci
Rod length 6.800
Deck height 0
Block height 10.200
Head gasket thickness 0.040
Main bearing clearance 0.0023-0.0025
Rod bearing clearance 0.0022-0.0025
Piston-to-wall clearance 0.005
Piston dome volume -28 cc
Piston compression height 1.150
Top ring gap 0.025
Second ring gap 0.025
Compression ratio 10.8:1
Camshaft (Comp Cams) 248/254-at-0.050; 0.647/0.647; 114
Installed centerline 114 degrees
Rocker ratio 1.7:1
Valves 2.200/1.615 intake/exhaust
Valvespring diameter 1.539
Valvespring seat pressure 150 lb
Valvespring open pressure 440 lb
Intake manifold Factory GM LS7
Fuel 93 octane unleaded
Measurements in inches unless otherwise noted
ON MOTOR
RPM LB-FT HP
4,300 570 466
4,400 582 488
4,500 600 514
4,600 615 538
4,700 622 557
4,800 626 572
4,900 628 586
5,000 629 599
5,100 630 612
5,200 629 623
5,300 627 633
5,400 625 643
5,500 622 651
5,600 618 659
5,700 614 667
5,800 611 675
5,900 609 684
6,000 608 694
6,100 605 703
6,200 601 709
6,300 595 713
6,400 588 716
6,500 579 717
  Avg. Torque 608
  Avg. Power 620
ON SPRAY
RPM LB-FT HP
4,100 597 467
4,200 606 484
4,300 617 506
4,400 626 525
4,500 644 552
4,600 737 646
4,700 866 776
4,800 906 828
4,900 905 845
5,000 904 861
5,100 903 877
5,200 898 889
5,300 889 897
5,400 878 903
5,500 869 910
5,600 857 914
5,700 847 919
5,800 835 922
5,900 821 923
6,000 807 922
6,100 792 920
6,200 777 918
6,300 761 913
  Avg. Torque 797
  Avg. Power 797
Sources
ERL Performance
812.948.8484
erlperformance.com
School of Automotive Machinists
713.683.3817
samracing.com
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