Last month, we started on an unusually large small-block Ford engine. The short-block was built in collaboration with Rich Groh Racing and Pro Power Performance Parts, and the massive Windsor is being constructed with complete street worthiness in mind.
To accomplish the goal, the parties involved came up with a 445ci solution to our problem. They took a World Products Man O' War block and bored the cylinders to 4.155 inches. The Man O' War block is one of the few on the Ford market capable of handling a huge bore without filling in the cooling passages with concrete or block fill for added strength.
They also stuffed a Prime One 4.100-inch crankshaft into the crankcase to jump the cubes even more. The short-block is sure to handle almost anything we throw at it-within reason, of course. The short-block is the foundation on which we will build a street beast that will hang with even the most hard-core '03-'04 Cobras and other nasty street machines lurking around our neighborhood. This mill will also benefit from a Vortech YSi-Trim supercharger that will breathe 12-14 psi of boost into the Edelbrock Super Victor intake manifold.
Some may argue that running such a long stroke puts undue stress on the piston skirts due to side load. Side load can come from a short connecting rod coupled with a long-stroke crankshaft. There is an angle that pushes excessively on one side of the piston. With those theories out and about in the engine-building community, why would anyone want to build an engine with such a big stroker crankshaft? It is easily explained: "Side load comes from poor rod-to-stroke ratios. What is an acceptable ratio before there is a problem? The rod-to-stroke ratio of this combination is 1.51:1. To put that into perspective, there are OE engines that have worse rod-to-stroke ratios than the one in this engine," says Dale Metlika of Pro Power. He discussed with us the finer points of side loading and explained that our engine buildup was not excessive.
Metlika also brought up the importance of oiling and how it helps prevent excessive wear in a short rod, long-stroke engine. For those who read Part 1, you may remember us discussing the finer points of oiling with this engine. One of the features Groh incorporated was a medium plateau hone. It was meant to promote better oil retention on the cylinder walls. The bore surface was flat, but there are microscopic grooves to help retain oil on the walls. A piston does not rub against the wall. Rather, it glides on a film of oil, so the piston is technically not smashing into the side of the bore with every up and down motion. The Prime One/Pro Power pistons also have provisions for oil retention on the skirts, so there is no shortage of oil as the pistons move up and down. Another hot topic is ring wear because of side load. Pro Power includes rings in its stroker kits that are beefy and long lasting.
A Superflow SF-600 has been...
A Superflow SF-600 has been properly calibrated for the shop location of Rich Groh Racing. The CNC-ported TFS heads were bolted to this machine, and the intake and exhaust ports were flowed.
Procedure is critical when...
Procedure is critical when flowing cylinder heads. Groh (shown) prides himself on being consistent and accurate with his testing. The flow bench has been calibrated by Superflow, and he continually checks it for accuracy through a standard procedure.
In the old days, head porters...
In the old days, head porters relied on bubbles and scales to read the results. Those results would then be plotted into a formula, and flow numbers were the outcome. Errors or misstated numbers were common because of inherent problems when reading the test tubes. Times are changing thanks to FlowCom. This tool is a digital readout that accurately reads the flow and converts it to the cfm reading we all recognize. It removes human reading and calculation errors from the equation so that the information is accurate.