Vetting the Value Short-Block
After following the assembly of our Value Short-Block project, we were more than a little curious about its potential as a complete engine.
"No problem," Katech's Caleb Newman said. "Follow me."He led us to one of the company's several engine dynamometers-Katech builds racing engines for the C6.R effort, remember-where a fully dressed Value Short-Block-based 427 was getting a workout. It was an engine built to a customer's specifications, but the block and reciprocating assembly were the same as we outlined in our main story.
On top of that, this engine also featured:
11.1:1 compression
L92 ported cylinder heads
L76 intake manifold
GM Stage III camshaft with 0.595/0.595-inch lift and233/277 degrees of duration; 107 LSA and 103-degree timing
1.7-ratio rockers
LS7 fuel injectors and ignition coils
90mm throttle body
MEFI-4 controller (for dyno use)
This combination of off-the-shelf parts demonstrated once again that, unlike modern engine families from other manufacturers, LS-based engines don't need a power adder to make killer dyno numbers. In this case, the naturally aspirated 427 made 604 hp and 566 lb-ft of torque.
And the peak numbers are only part of the story. Peak horsepower occurred past the 6,000-rpm mark, but the engine was making more than 500 horses before 4,800 rpm, and never dropped below 580 horses between approximately 5,550 and 6,800 rpm.
The torque story was equally compelling: 500 lb-ft was achieved at a low 3,100 rpm and held above that mark past 6,100 rpm. Yes, the phrase "stump puller" is tossed around liberally in car magazines, but how else could this engine be described? A "forest puller"?
Crank journal roundness is checked at Katech not with a caliper, but a sophisticated air tool that uses air pressure to provide a more accurate "picture" of the journals' dimensions. In the case of the Value Short-Block's 4.00-inch crank, the rod journals need to come in between 2.0989 and 2.0994 inches, while mains' spec range is between 2.5590 and 2.5595 inches. | 
Here's a close-up look at the Air Gage tool used during several blueprinting steps in the Value Short-Block's assembly. It is shown being calibrated for the crankshaft journals. Once the correct specification is achieved during calibration, the tool is placed on the crankshaft and new measurements are taken. And just like using a caliper, the builder looks for a measurement within the manufacturer's specification range. | 
With crankshaft balancing and blueprinting finished, work moves to assembling the short-block. First, the factory-type main bearings are installed. |