Snellerized MS461 on the dyno

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OK guys. I went back through some of my papers and found I changed my calculations that are in my spreadsheet. Duh stupid me. I guess I'd figure the stock 461 of mine did gain a little but not that much. Still the gain over stock still stands true. Do not compare my old graphs with new ones.
Naturally my dyno has some drag and the hp lower than expected on all saws. I ran multiple stock saws and reviewed my results and compared them to Stihls hp specs. I then did some calculations and came up with a # that all my hp #s get multiplied by to get a more realistic #. I'm sticking with this calculation now.
 
Wasn't that change before any of the 461 tests? I believe you sorted that out when testing the 660. Before that, your numbers were coming out too high. Your numbers were matching factory specs well before your last 461 run. Factory spec is 5.9, almost exactly what yours ran in August.

ENGINE POWER
4.4 kW (5.9 bhp)
 
I'm working now so I'll have to wait till I get home to check. I think I might have picked the wrong saved spreadsheet on my laptop. If I can I'll run the data again in the same spreadsheet I was using before
 
I'm working now so I'll have to wait till I get home to check. I think I might have picked the wrong saved spreadsheet on my laptop. If I can I'll run the data again in the same spreadsheet I was using before

I can see a stock saw loosening up quite a bit. Heck, I've seen it myself. But .75hp increase? That's a crap ton...
 
I looked back in the weather archives and found the weather data for the August date when I tested it and yesterdays data and entered it in the calculator. .944 correction brings yesterdays stock 461 max hp to 6.4hp. 8/22/14 has a correction of 1.008 bringing its max hp to 6.04 hp
So with the corrections added my stock 461 gained .36 hp since it was last tested. That could have very well been from a good thorough break in.
I can see a stock saw loosening up quite a bit. Heck, I've seen it myself. But .75hp increase? That's a crap ton...
It was only .36 HP gain after weather corrections. That I can see.
 
Ok I've got a question and I'm not trying to burst anyone's bubble here.

So when I broke in my 461 (bought brand new). Honestly it was just a DOG for the first 3-5 tanks. Around tank 6-8 it just became a totally different saw.

So if the dyno is saying broken in 461 gained just ~.4 more horsepower over a new saw.... then there has to be something missing here? Cuz a .4 horsepower gain...to me anyway, doesn't explain the difference I saw.
Your opinion is smelly...like butthole. Don't you have some bars to sell. :happybanana::cheers:
 
.4 hp on the total is only about a 5% gain. Going from dog to wow this is pretty nice ...gotta be more than just 5%.

There should be like a 10 tank min before any saw is tested. IMHO :) That way we know it's all broken in etc etc etc.
I would like to have them all broken in before I get them.
Ok I've got a question and I'm not trying to burst anyone's bubble here.

So when I broke in my 461 (bought brand new). Honestly it was just a DOG for the first 3-5 tanks. Around tank 6-8 it just became a totally different saw.

So if the dyno is saying broken in 461 gained just ~.4 more horsepower over a new saw.... then there has to be something missing here? Cuz a .4 horsepower gain...to me anyway, doesn't explain the difference I saw.
.4 HP on a 6 HP saw is 6.6% gain. That would be like boosting a 300 HP engine to 320 HP
 
Get a chance to figure it out?
Yep. My #'s stand true. I went back to the saved spreadsheet from the ported 461 I tested back in August and input my stock #'s from this past weekend and come up with the same #'s. So there was only a .36 HP gain after the #'s were plugged into the Weather calculator. I'm guessing the stock gain of .36 HP came from the heavy use of my 461 with a 36" bar since it was last tested.
 
I'm home with my sick three year old today so I'll probably be here a bunch today.

I did a couple calculations that might put some things into perspective.

Stock 461 VS Snellrized 461
9,000 rpms = 15.1% gain= 300 HP engine boosted to 345 HP
10,000 rpms = 20.8% gain= 300 HP engine boosted to 362 HP
11,000 rpms = 26.8% gain= 300 HP engine boosted to 380 HP
12,000 rpms = 49.2% gain= 300 HP engine boosted to 447 HP
13,000 rpms = 58.6% gain= 300 HP engine boosted to 476 HP
 
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