Back up saw

[burrell_]

lol i lost ur pic of ur port and the 2nd reasion is time (2 many projects)

[White Noise]

lol i lost ur pic of ur port and the 2nd reasion is time (2 many projects)

 

To many projects I can relate to lol:biggrin:

[Pete Tattam]

I be you ain't ported that exhaust yet eh ? You'll be amazed at the extra hp

 

I've read several comments on other threads about increasing saw power but don't know what is being suggested (sorry but I'm a simple sort). What is "porting an exhaust"?

[spudulike]

I've read several comments on other threads about increasing saw power but don't know what is being suggested (sorry but I'm a simple sort). What is "porting an exhaust"?

 

Saw tuning can be done in stages, the "muffler mod" in basic terms is forgetting about the 114db limit and opening up the outlet and baffle plates to 80% of the exhaust port area. This mod has greater effect on more modern restrictive exhausts than older free breathing ones.

 

This can be followed by opening up the exhaust PORT and inlet PORT, this increases the flow of vapour and exhaust in and out of the engine. Transfers can be worked on increasing the flow from the crankcase to the combustion chamber.

 

Squish height can be decreased with a mix of lower gasket, pop up piston or machining the cylinder to lower the squish height to increase the compression.

 

Timing of the engine can be changed by adjusting duration and port height but leave this for the real experts.

[Pete Tattam]

Saw tuning can be done in stages, the "muffler mod" in basic terms is forgetting about the 114db limit and opening up the outlet and baffle plates to 80% of the exhaust port area. This mod has greater effect on more modern restrictive exhausts than older free breathing ones.

 

This can be followed by opening up the exhaust PORT and inlet PORT, this increases the flow of vapour and exhaust in and out of the engine. Transfers can be worked on increasing the flow from the crankcase to the combustion chamber.

 

Squish height can be decreased with a mix of lower gasket, pop up piston or machining the cylinder to lower the squish height to increase the compression.

 

Timing of the engine can be changed by adjusting duration and port height but leave this for the real experts.

 

Thanks Spudulike but you may as well have been writing in Chinese 'cos I didn't understand a word of it! Obviously you need a modicum of engineering knowledge to do this and I very definitely don't. I thought it may have been a process that even a dozy idiot like me could undertake. Wrong again!

[swinny]

As said buy a secondhand stihl or husky.... whats your budget?

 

what size of saw/cc are you after also?

[Pete Tattam]

As said buy a secondhand stihl or husky.... whats your budget?

 

what size of saw/cc are you after also?

 

Just been offered semi-permanent loan of MS260 so happy as a pig in muck at the moment. thanks for advice

[spudulike]

Just been offered semi-permanent loan of MS260 so happy as a pig in muck at the moment. thanks for advice

 

That saw should do the job - will refrain from talking Chinese in future - always wondered why people glaze over when I start talking saws - and why Burrel has never visited:lol: