Guys. Had a great time at the Engine Masters Challenge and would definitely do it again. I entered a 375 inch Y which ended up being too big an engine for the iron heads to have a really good score. At 6700 rpms, the engine was just out of air. Good peak numbers though and that’s what I was counting on. The 316 incher I readied for last years competition would have had a much better score at the expense of reduced peak numbers. The big numbers did not rule at this competition as there were several 800 plus horsepower engines but their average scores were down compared to the smaller engines. Triple thanks goes to the other Y team members who assisted me at the EMC site which included Jody Orsag, Harry Hutten, Jerry Christenson, and Royce Brechler.
The 375 got that way by way of a 3.859” bore with a 4.00” stroke. Pistons with a 9cc dish gave me a 10.1:1 static compression ratio and 9.0:1 dynamic compression ratio. And the engine idled like a champ with a healthy rumble at 900 rpms through the mufflers. The original plan was to enter the 4.00” bore X 4.00” stroke combination (403 CID) but the block just ended up not being strong enough once the cylinders were bored out and replaced with sleeves. That engine ultimately twisted the block on a moderate dyno pull to the point the camshaft was difficult to remove. A new set of pistons arrived in the middle of September for the 375” combination at which point the assembly of a new and smaller sized Y started going back together.
On my dyno, the 375 incher was peaking 462-464HP and 446-449 lbs/ft torque. At the EMC competition, I lost numbers like the other competitors. The best EMC numbers after tuning changes in preparation for the qualifying session netted the Y team 433HP and 416 lbs/ft torque peak values. Still not too shabby for an engine We could have put back in a car (or truck) and driven back home on pump gas. Although I tested the engine at 7000 rpms on my end, it was pushed to 7400-7500 rpms during the competition. It held up just fine to the surprise of everyone at the competition. After 49 pulls on my own dyno, I was reasonably confident that the engine was not going to be easy to hurt. I had already increased the over the nose valve spring pressure from 330 lbs to 388 lbs during the course of testing just to insure that the rpm capability was going to be there. The Isky cam and lifters are showing no signs of wear after all of this abuse.
The electric water pump is an Ebay big block scrub electric pump that I gutted and then made an aluminum plate to adapt it to the Y engine. Although I had reservations about using it in the competition due to some air lock issues that were cropping up, it worked just fine in the competition. In fact, the engine temperatures with each qualifying pull were consecutively dropping and the last pull was at 136°F which was in itself a performance deterrent. When I build a new version of the electric pump, I do have a plan on how to make the pump self priming and eliminate the air block issue.
And that’s the short story of what happened at the Engine Masters Challenge.
Lorena, Texas (South of Waco)