High Quality Chainsaw Bars Husqvarna Toys

Chainsaw Porting Theory

Mastermind

Chief Cat Herder
Staff member
GoldMember
Local time
9:43 AM
User ID
4
Joined
Dec 3, 2015
Messages
47,904
Reaction score
310,726
Location
Banner Springs Tennessee
Country flag
A lot of guys ask me why we choose the port timing numbers we do.....or why we would want to lower an exhaust port, when all the two stroke tuners books clearly say a higher exhaust will provide more horsepower....

Let's kick some of these things around......

Questions?
 

idiotwithasaw

Super OPE Member
Local time
9:43 AM
User ID
370
Joined
Dec 31, 2015
Messages
1,004
Reaction score
1,322
Location
Ky
Subbed

Sent from my HTC One using Tapatalk
 

pud

Well-Known OPE Member
Local time
10:43 PM
User ID
618
Joined
Jan 20, 2016
Messages
17
Reaction score
59
Location
Albany Western Australia
Im always curious to know how u decide what way to go when u run a stock saw , for example this saw needs more intake or higher transfers ? Is it traits that u pick up on from running lots of saws and studying them and a lot of trial and error ... Lower exhaust makes sense to me , longer stroke build more compression ect
 

smokey7

Pinnacle OPE Member
Local time
10:43 AM
User ID
761
Joined
Feb 3, 2016
Messages
1,537
Reaction score
3,553
Location
Detroit
Country flag
Awesome I am following closely.
 

Moparmyway

Its just a saw
GoldMember
Local time
10:43 AM
User ID
21
Joined
Dec 4, 2015
Messages
5,237
Reaction score
28,046
Location
In a meeting
Country flag
Im always curious to know how u decide what way to go when u run a stock saw , for example this saw needs more intake or higher transfers ? Is it traits that u pick up on from running lots of saws and studying them and a lot of trial and error ... Lower exhaust makes sense to me , longer stroke build more compression ect

I'd say its about 40% traits from running lots of saws after the 60% of trial and errors

The best way to answer most porting questions is to be saw specific, as what works with one saw does not necessarily work with another saw.
Yes, some theories do apply to all saws, but the best way to see what works is to change one thing, then run the saw.
If you gain, make a note and keep going ........... if you lose, chalk it up, make a note, and dont go further in that one area

Just because Homer Simpson hogs out his lower transferrs does not mean that everyone should do the same thing. Homer might be doing other things to the motor that allow the lowers to respond better to being hogged out

Here is where the rubber meets the road .................the more you know about 2 strokes, the more you realize that you dont know squat about them.
Just when you begin to understand what youre doing, someone will come along and throw an idea at you, which makes you think that what you were origionally thinking about shouldnt or wont work.
 

quietfly

Pinnacle OPE Member
Local time
10:43 AM
User ID
791
Joined
Feb 5, 2016
Messages
557
Reaction score
2,085
Location
Northern NJ
Country flag
So ill be the first to admit i know nothing about non nitro methane running 2 strokes. The little high revving whiny motors im used to porting polishing and tuning, are way different than our larger displacement wood killing ones, and im out of my comfort zone. When porting a large displacement saw like an 084, what sweet spot are you looking for?
Is it just your previous knowledge of past work that lets you know where you are and how far you can go?
 

Simondo

Here For The Long Haul!
Local time
3:43 PM
User ID
821
Joined
Feb 7, 2016
Messages
3,425
Reaction score
10,659
Location
UK
A lot of guys ask me why we choose the port timing numbers we do.....or why we would want to lower an exhaust port, when all the two stroke tuners books clearly say a higher exhaust will provide more horsepower....

Let's kick some of these things around......

Questions?
Brilliant thread to start Mr M !!!
My question is based around that thing.. what sets you off in a direction with a cylinder ? Can one be looked over as to how its been designed and that would tell you how it lends its self to work and what the appropriate treatment may be along with how far you want to take things ..OR.. is it Numbers ,numbers Numbers ..first and that can start the brain a ticking. Is there a basic.. GO TO.. start point to build on. :)
 

Ray Bell

Well-Known OPE Member
Local time
7:43 AM
User ID
823
Joined
Feb 7, 2016
Messages
21
Reaction score
36
Location
Washington
I am always curious about the use of epoxies, jb weld, etc used to buildup/reconfigure. Does this ever come loose or fall out? Granted I have limited experience with these materials, but seems the heat and vibrations would eventually break this loose.
 

jmssaws

Banneded
Local time
9:43 AM
User ID
291
Joined
Dec 28, 2015
Messages
10,024
Reaction score
37,288
Location
Missouri
I am always curious about the use of epoxies, jb weld, etc used to buildup/reconfigure. Does this ever come loose or fall out? Granted I have limited experience with these materials, but seems the heat and vibrations would eventually break this loose.
I've used jb weld for a long while and haven't had any problems. Vibration is about all that can cause trouble.
 
Top