VP 101-octane unleaded was utilized in the cell (TSP says 93-octane would work just as well), fed to the engine via the shop's Aeromotive fuel pump, and regulated to 58 psi. Please note that the brake-specific fuel curve (BSFC) shown on the dyno graphs is inaccurate, as it is measuring the amount of fuel moved through the dyno's fuel cell rather than through the engine. In order to ensure consistency in the test results, the various combinations were pulled after the engine had recorded 165 degrees on the test cell's DTS model S-1007M engine cooling system. The DTS specific cooling system provides for the cooling requirements of the engine, and no engine accessory belts were required, since a Meziere electric water pump was utilized.
Once the engine reached the proper temperature, the dyno operator took it to 3,800 rpm and then applied a dyno load. Once loaded, the engine was slowly brought up to 3,000 rpm and then pulled until the specified redline. Standardized SAE calculations were used to correct the horsepower and torque to industry standards. Reference temperatures for SAE calculations are 77 degrees Fahrenheit and a barometric pressure of 29.23 inches of mercury.
In order to get the long,...
In order to get the long, 6.125-inch Eagle connecting rods to clear the block when used with a forged 4.10-inch stroke, the bottom of the bores are clearanced with a carbide bit. After the cast-iron is removed, a sanding roll is employed to smooth and radius each cut.
The block is then honed in...
The block is then honed in a Sunnen CV616 Cylinder King honing machine, after which, GM LSX cam bearings are installed. The rotating assembly is balanced on a Sunnen DCF-2000 electronic balancer and then the ACL main bearings and bearing clearances are established. The main bearings are lubricated, the balanced Eagle crank is lowered into position, and then the caps are installed and torqued to spec. Eagle's crank is a non-twist forged unit constructed of 4340 alloy steel and features micropolished journals and a 0.125-inch radius in the oil journals. Jason Mangum, co-owner of Texas Speed notes, "The crank is used for naturally aspirated and forced-induction applications and takes very little preparation to achieve our balance specs. Though it is reasonably priced, it offers high-strength and value."
A set of custom-made Diamond...
A set of custom-made Diamond Racing Products forged pistons are used in combination with Total Seal piston rings to ensure the 11:5.1-compression crate engine will be able to reliably live on the street or at the track. Jason continues, "The pistons use 2618 alloy with 3.8cc valve reliefs and are considered severe-duty and power-adder capable. With the ring pack specified for the pistons, you can reliably run a 150 shot of nitrous. For max-effort naturally aspirated racing or boosted applications, custom Diamond or Wiseco pistons are available for the 454 LSX for an additional $325." The connecting rod is an Eagle H-beam forged 4340 unit that uses a 0.927-inch wristpin supplied by Diamond Racing/Trend Performance. Double Spiralox retainers are employed with the free-floating wristpin.
After installing the pistons...
After installing the pistons and rods with bearings in the oiled cylinders using a tapered ring compressor and assembly lube, the rod caps are retained with ARP 2000 bolts and are torqued to spec, and the bearing-cap side bolts are installed (five on each side) and torqued. Once complete, the crankshaft endplay clearance is verified. A dial indicator is then set up on a bridge over each piston and the piston-to-deck height is measured.
The remaining assembly goes...
The remaining assembly goes to Texas Speed, where lead technician Joseph Potak installs a TSP ported-and-shimmed LS6 oil pump and a stock GM LS2 windage tray, oil pan, filter, LS7 hydraulic rollers, and valley plate. The block is then fitted with two new GM cylinder-head aligning dowels per bank, and Cometic's LSX 4.205-inch-bore head gaskets before lowering on a set of unported LS7 heads. Optional ARP hex-head bolts are lubricated and torqued.
Kooks Custom Headers were...
Kooks Custom Headers were bolted onto the heads with new GM exhaust-manifold gaskets and stock exhaust bolts. The headers utilize 1.875 to 2-inch stepped primaries with a 3-inch collector. Both the primary and collector lengths were increased to 35 and 8-inches, respectively. Once in position, a fresh set of NGK TR6 spark plugs and MSD 8.5mm Superconductor wires were installed, as was a dipstick tube (passenger side). The LS7 heads have cast-in bosses unlike other LS engines that require a rocker pedestal stand. Stock GM LS7 rocker arms are offset on the intake, and both intake and exhaust rockers feature an aggressive 1.8:1 rocker ratio.