Some engines have a certain sound. Fury. Hate. Anger. They emanate total power. This engine makes that sound. It makes that power. When the throttle goes WFO on this thing, the little hairs on your arm stand straight up, and you get that special feeling that lets you know something really good is happening. Like listening to Metallica's "One," it just builds and builds and you can't help wanting more. Once the final notes have played, the silence that remains is just as deafening.
Like a lot of hot rodders,...
Like a lot of hot rodders, we figured we could do some things ourselves a little cheaper than buying them-like building headers. Wrong. If we had to do it again, we'd buy a set of headers and maybe swap out the collectors for the awesome ones that Edelbrock makes. Our jaws dropped when they picked up 40 horses and an equal amount of torque over 4-2-1 collectors in testing. The one thing we don't regret is having Nitroplate coat our headers. Every time we've used them, we've seen an increase in power as well as bling.
Before breaking down the notes on this engine, let's first take a little trip back in time. In 1967, GM began selling high-performance engines over the counter and their line of offerings has steadily grown into the full-blown GM Performance Parts array of crate engines that we see today. Dr. Jamie Meyer of GMPP says the 572 that they based their build on was originally offered for sale in 2003 and has been a number one hit ever since. He also stresses that GM is the only source for brand-new Chevy engines. "If you buy a 350 Chevy from someone else, you just bought a used engine. That holds true for the big-block series as well-427 and 454. We are still making brand-new Chevy big-blocks every day." As a side note, we just got word that GMPP dropped the pricing of their ZZ427 so that enthusiasts can pick up a modern version of the fabled L88 direct from GM on the cheap. They even have a few of the limited Anniversary Edition 427s floating around in dealer inventory if you want something real special.
The 572 offered from GMPP is designed as a 4.560-inch bore by 4.375-inch stroke combination using rectangle-port aluminum heads on a tall-deck Gen VI block. We built our instrument using a short-deck version of the famous Bow Tie block with the bore and stroke dimensions matching that of the crate engine. Naturally, we used a torque plate to stress the block while honing, simulating the effects of torquing the heads in place. For the honing procedure, it seems like all machine shops have their own secret way of finishing the bores. We've found great results with our Sunnen CK10 by roughing it in to the last thousandth of an inch with a 180-grit stone, using a 220-grit to get to finished size, then running four strokes with a 280-grit and four strokes with a 400-grit. Since we were going for the gusto, we also hit this block with four strokes of a 600-grit stone. Clean honing fluid, the right pressure on the stones, and a good feel for the machine are the tricks to getting the holes round and straight to within a couple ten-thousandths of an inch.
With an engine nearly as big...
With an engine nearly as big as the team, the guys at Revolutionary Performance and Machine were proud of their handiwork. From left, Shannon Carnathan, engine owner Kris Henderson, author Daryl White, Derrick Goodwin, and Michael Schoeder put in a lot of effort to make this piece of heavy metal look like just another crate engine with an intake swap.
The rotating assembly is sort of like the rhythm section of this band. It is always moving, making the cadence and striking the beat that the rest of the players follow. At the very bottom, a Kryptonite crankshaft made from EN30B billet steel spins to the beat. It was a bargain that engine owner Kris Henderson scored from a buddy's blown-up offshore powerboat. A couple hundred bucks for a crank that usually costs close to $3K is a real deal.
Eagle Specialty Products supplied a set of their Armor-coated 6.385-inch-long H-beam rods with the L19 bolt upgrade. Using a rod bolt stretch gauge, we determined that it takes right about 80 ft-lb to give the bolts .0058 inch worth of stretch. That tension on the bolts is what keeps the fasteners from backing out and the added tensile strength of the L19 material keeps the rod bearing bore from elongating and stretching out when the engine is at speed. I'll be honest, I was slightly skeptical of the Armor coating that was on the rods, but really the oil would just about bead up on it, and you could feel how much slicker it was than an untreated rod. For the small amount of
the upgrade price, it was absolutely worth it.