Dyno tested....Mastermind's ported 261cm vs Stock 261cm Gotta see this one.

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The gains are great, but I'm more impressed with the plateau of power from 10,000 - 11,500 RPM. Hopefully, the engine will stay in that range "in the cut".

That range is so dramatically different from the stock saw that you would not know the two were related.

Great job Randy. This graph is just further validation of what everyone says about your work, and your own internal testing.

And Chad, you can have a new career if you want it (full or part time). There will be no end to builders and customers who want to see what their saw can do.

You may need to "climate control" your testing area so that all results are comparable.
 
Good job on the saw and the dyno!

As for the "dip", there is no way to tell if it is even there. Those numbers are probably well within the margin of error and the resolution of the dyno (no denigration intended at all). What you see in these graphs is the characteristics of the saw superimposed on the characteristics of the dyno. The dyno must have some error curve to it as few things are perfect, and since it would be quite difficult to baseline the dyno characteristic by itself then the best use is to compare the two saws rather than as a absolute HP output from one saw.
 
Good job on the saw and the dyno!

As for the "dip", there is no way to tell if it is even there. Those numbers are probably well within the margin of error and the resolution of the dyno (no denigration intended at all). What you see in these graphs is the characteristics of the saw superimposed on the characteristics of the dyno. The dyno must have some error curve to it as few things are perfect, and since it would be quite difficult to baseline the dyno characteristic by itself then the best use is to compare the two saws rather than as a absolute HP output from one saw.

His dyno is very accurate. Stihl factory specs for a stock 261 is 3.8 HP. His graph shows the stock 261 peaking at 3.8 HP.
 
For all of you guys that say to run a stock saw 10000 to 12000 rpm in the cut you are full of bs and these HP charts prove it, modded is a different story. I'll be reminding you any time I hear my saw holds 12000 rpm in the cut unless it's been modded. Steve
 
His dyno is very accurate. Stihl factory specs for a stock 261 is 3.8 HP. His graph shows the stock 261 peaking at 3.8 HP.
No my dyno reads lower HP than Stihl states. I have some drag that I account for. There's lots of calculations from testing to line graph making. Good thing I paid attention in math class. Every dyno has #s to add.
 
For all of you guys that say to run a stock saw 10000 to 12000 rpm in the cut you are full of bs and these HP charts prove it, modded is a different story. I'll be reminding you any time I hear my saw holds 12000 rpm in the cut unless it's been modded. Steve
Unless it's an Echo. I hear those will hold 12k in the cut if you mod the muffler and ditch the H jet limiter.:D
 
Unless it's an Echo. I hear those will hold 12k in the cut if you mod the muffler and ditch the H jet limiter.:D
You got that backwards, ditch the limiter and crank in the h needle till she's running on fumes. She'll hold 12k in the cut for at least half a tank.
 
You won't find one tread about me bragging that my saw holds 11000 to 12000 rpm in the cut, I run them where they cut the fastest around 9000 to 9500 Rpm. If anyone is running a stock saw at 11000 to 12000 lean on it a little and it will get down to 9000 to 9500 and cut faster.. The same mountain lake Steve
 
You won't find one tread about me bragging that my saw holds 11000 to 12000 rpm in the cut, I run them where they cut the fastest around 9000 to 9500 Rpm. If anyone is running a stock saw at 11000 to 12000 lean on it a little and it will get down to 9000 to 9500 and cut faster.. The same mountain lake Steve
I was merely jesting about your passionate saw preference. No offense intended, and I was not implying you ever made 12k in the wood claims
 
My guess would be that there isn't as much magic going on with these chips as we imagine. They are after all, Gen. 1. Processors. What are the claims? Temp, altitude, fuel quality. That's about it. I'm sure they went with reliability over sophistication for their first rodeo.
Not even that much magic. The ignition module senses RPM and crankcase temp. That's it.
 
Not even that much magic. The ignition module senses RPM and crankcase temp. That's it.
I think the system is really quite clever, mainly because it is so darn simple - no sensors! I think its biggest drawback is that it can only work at a fixed (WOT) throttle position, but this is OK for a saw.
 

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