High Quality Chainsaw Bars Husqvarna Toys

That is interesting

Red97

Mastermind Approved!
GoldMember
Local time
7:37 PM
User ID
385
Joined
Jan 2, 2016
Messages
7,452
Reaction score
53,843
Location
MI
Country flag
Just something I noticed with these strato saws, figured it could start a good discussion.

20230328_110433.jpg

One of these makes about 10hp and the other is around 4.5hp

Knew the intake was small, but didn't realize it was that small.

881 right, 550xp left
 

Stump Shot

Disciple of Monkey's
GoldMember
Local time
6:37 PM
User ID
1377
Joined
Jun 5, 2016
Messages
30,974
Reaction score
193,740
Location
Northwoods of Wisconsin
Country flag
Look to the strato's and their butterfly valves to make up the difference in volume. The carburetor doesn't need to be bigger, just needs to be able to meter the extra amount of fuel out so when it finally gets all mixed up it ends up at the proper amount. As with bigger strato's the cleaner, more efficient the whole process is.
 

Mastermind

Chief Cat Herder
Staff member
GoldMember
Local time
6:37 PM
User ID
4
Joined
Dec 3, 2015
Messages
47,628
Reaction score
308,434
Location
Banner Springs Tennessee
Country flag
Just something I noticed with these strato saws, figured it could start a good discussion.

View attachment 371599

One of these makes about 10hp and the other is around 4.5hp

Knew the intake was small, but didn't realize it was that small.

881 right, 550xp left
Look at the transfer inlet AND the intake port. Then ask yourself how it makes 10hp using those small passages.

Hint....it ain't the fuel side of the system that makes the power.

Strato engines often have over 100% of the bore in total intake width.
 

Stump Shot

Disciple of Monkey's
GoldMember
Local time
6:37 PM
User ID
1377
Joined
Jun 5, 2016
Messages
30,974
Reaction score
193,740
Location
Northwoods of Wisconsin
Country flag
Yes, bigger carb, but split design, as well as the big one doesn't go anywhere near the RPM of the little one reducing its requirements in that respect. A bunch of math will explain it best, I believe.
 

Mastermind

Chief Cat Herder
Staff member
GoldMember
Local time
6:37 PM
User ID
4
Joined
Dec 3, 2015
Messages
47,628
Reaction score
308,434
Location
Banner Springs Tennessee
Country flag
Yes, bigger carb, but split design, as well as the big one doesn't go anywhere near the RPM of the little one reducing its requirements in that respect. A bunch of math will explain it best, I believe.
Carb isn't divided. Intake is though.
 

Red97

Mastermind Approved!
GoldMember
Local time
7:37 PM
User ID
385
Joined
Jan 2, 2016
Messages
7,452
Reaction score
53,843
Location
MI
Country flag
20230329_104732.jpg

The strato inlet area appears similar.

The outlet area is for sure smaller on the 550.

I just found it mighty interesting is all
 

Red97

Mastermind Approved!
GoldMember
Local time
7:37 PM
User ID
385
Joined
Jan 2, 2016
Messages
7,452
Reaction score
53,843
Location
MI
Country flag
Like Randy said, it's the length. I can imagine it taking less than a blink in time to fill.
Yeh the 550 has a longer strato length. From the boot to the first entry to the cylinder wall.
 

Ketchup

Epoxy member
Local time
5:37 PM
User ID
5594
Joined
Mar 12, 2018
Messages
1,756
Reaction score
4,853
Location
Colorado
Country flag
Just something I noticed with these strato saws, figured it could start a good discussion.

View attachment 371599

One of these makes about 10hp and the other is around 4.5hp

Knew the intake was small, but didn't realize it was that small.

881 right, 550xp left
Look at the transfer lowers.
 

Ketchup

Epoxy member
Local time
5:37 PM
User ID
5594
Joined
Mar 12, 2018
Messages
1,756
Reaction score
4,853
Location
Colorado
Country flag
550 has large lowers for sure. All the 5 series husky are rather large.
Yeah, I think the stuffed huskies hold a lot of their case volume in the transfers. They also push the flow out to the sides a lot more abruptly.

Does the case gasket divide the transfer feed in a 881 case like it does in a 462?
 
Top