Explain to me again, please

[SSDiv6]

Originally Posted by L.Fite

The point, however, is that if a 750-850 HP, 358 CID, canted valve, flat tappet engine in a Cup car can run 500 miles at over 9000 rpm with a stock diameter solid lifter, then it's hard to imagine why it can't be done in a stocker that doesn't anywhere near that RPM and is raced a quarter-mile at a time.

You're still comparing apples to grapes...

The technology used to make a NASCAR engine live is so for advanced it makes a SS engine look like a high school mechanics class project.

I worked for a period of time for the former engine shop director for Robert Yates, Penske Racing and later on, Richard Petty. He spent lots of time sharing tidbits of the technology used in NASCAR on racing engine building. The only aspects that I see are advanced in NASCAR is the machining processes, equipment and materials used in the parts for longevity. Of course, they also spend millions on R&D and testing, and yes, we run more radical camshafts. Nevertheless, some of the qualifying engine cams have radical profiles and spent lots of hours and days doing Spintron testing, learning to control the valvetrain that is one of the main keys for making power.

As regards to camshafts, the cores are billet and treated. The camshafts are not broken in th engine. Every camshaft is broken-in by installing the cam in a specific machine the simulates the lifter contact and load, and different RPM levels and temperatures, being sprayed with engine oil during the operation. After the camshaft was broken in, then it would go into the assigned engine. The choice of hardened steel solid lifters made by either Trend, PPPC, Isky and Crower.

The other key for making power in NASCAR is sealing the engine, spending lots of time testing hone finishes and piston ring materials and configurations. All the torque plates we had in the shop, were custom made. The thickness of the torque plates mirrored the height of the actual cylinder head, with all the fasteners and hardware having the same length and diameter as the ones used in the engine. They were not the normal thickness of torque plates used by most shops, and many of the torque plates had provisions for hot honing.

There is more to building a fast engine than putting a big cam and stiffer valve springs.