I finally bit the bullet and sent a saw to Chad to run on the dyno. This particular saw was built the same as all of my 461s, not knowing it was going to go on the dyno. Also, this saw is not nearly broken in, as it's still on only is first or second tank of fuel.
This graph does a great job of giving a visual representation of my build style, and why I build like I do. I talk a lot about demanding both RPMs and torque. If a saw doesn't have both, I'm not happy with the build. Notice how the ported saw makes as much or more HP than the max of the stock saw from about 7,500-12,000 RPMs. HP climbs earlier than the stock saw but at the same rate/curve. Once the stock saw maxes out, the ported saw just keeps climbing. Once it peaks, there's no abrupt fall off, and it tapers off nicely. It's making 6+ HP from <7,000 all the way up to almost 12,500.
Even more surprising than the results of my ported saw, are the results of the stock saw. This is the same saw that Chad ran on his dyno before, only this time, it's making 3/4 more HP. Since then, this saw has seen a lot of run time with a 36" bar, so is fully broken in. The same testing methodology was used. This really surprises me. I would have never guessed it would be that much. This would suggest that the ported saw should easily end up at 8.5+HP. I'll take that!
A couple details about how I build a 461. This saw has a .035" popup, resulting in 180-190 PSI compression. It's been several months since I built this saw, so I don't recall exactly what it was. I find that the 461 runs best with lots of intake duration and set the intake port timing at 85°. I've also found that it likes short blowdown, so have that set at 16°. I've tested other configurations, and this is where I find the 461 runs best. This saw is wearing a 046 coil and timing has been advanced about 6°.
This graph does a great job of giving a visual representation of my build style, and why I build like I do. I talk a lot about demanding both RPMs and torque. If a saw doesn't have both, I'm not happy with the build. Notice how the ported saw makes as much or more HP than the max of the stock saw from about 7,500-12,000 RPMs. HP climbs earlier than the stock saw but at the same rate/curve. Once the stock saw maxes out, the ported saw just keeps climbing. Once it peaks, there's no abrupt fall off, and it tapers off nicely. It's making 6+ HP from <7,000 all the way up to almost 12,500.
Even more surprising than the results of my ported saw, are the results of the stock saw. This is the same saw that Chad ran on his dyno before, only this time, it's making 3/4 more HP. Since then, this saw has seen a lot of run time with a 36" bar, so is fully broken in. The same testing methodology was used. This really surprises me. I would have never guessed it would be that much. This would suggest that the ported saw should easily end up at 8.5+HP. I'll take that!
A couple details about how I build a 461. This saw has a .035" popup, resulting in 180-190 PSI compression. It's been several months since I built this saw, so I don't recall exactly what it was. I find that the 461 runs best with lots of intake duration and set the intake port timing at 85°. I've also found that it likes short blowdown, so have that set at 16°. I've tested other configurations, and this is where I find the 461 runs best. This saw is wearing a 046 coil and timing has been advanced about 6°.
That's exactly what I shoot for. Chain speed is what cuts wood.
