Spuds Porting and Tuning Thread

[longblackcoat]

Spud

 

Does a muffler mod always increase the noise level? If so, how much?

 

I'm keen on more power, but not on more noise. This is for a 365 Special, completely stock.

[spudulike]

Spud

 

Does a muffler mod always increase the noise level? If so, how much?

 

I'm keen on more power, but not on more noise. This is for a 365 Special, completely stock.

 

A muffler mod will always increase the sound level just because you are letting the thing flow better. Some are louder than others - did a 362 a while ago and it was REALLY loud.

 

You can do things to keep the noise a bit lower but performance will drop off if you don't open it up much.

[Joe Newton]

Funny, since you made that 357 of mine "really angry", the saw noise has gone up, but everything else seems quieter.

 

Notably requests to hang washing out, or to not get wasted at dinner with her parents...

[spudulike]

Funny, since you made that 357 of mine "really angry", the saw noise has gone up, but everything else seems quieter.

 

Notably requests to hang washing out, or to not get wasted at dinner with her parents...

 

I think the modern expression is that "it is a win win situation":thumbup:

[monkeymoreton]

There is a solution better ear defenders

[Stubby]

What ? Speak up .......

[spudulike]

What ? Speak up .......

 

Not surprised you are stone deaf with your bad boy mufflers:001_rolleyes:

[spudulike]

Been porting another 357XP yesterday, turned out well, thought I would show a comparison of the standard exhaust port and the modded one. Lots can be done to these saws resulting in 30%+ gains.

[Sawchip]

Been porting another 357XP yesterday, turned out well, thought I would show a comparison of the standard exhaust port and the modded one. Lots can be done to these saws resulting in 30%+ gains.

Question if you don't mind me asking....is it a width change in your recipe on the port/ports in general or is it combined with any hight changes. I know there is a lot to describe if you gave a full description including transfer work (if done as well) so just a outline would be cool .

[spudulike]

Question if you don't mind me asking....is it a width change in your recipe on the port/ports in general or is it combined with any hight changes. I know there is a lot to describe if you gave a full description including transfer work (if done as well) so just a outline would be cool .

 

The amount a port can be modified is dictated by the width of the piston skirt, the ring ends and the maximum known safety margin that you work within.

 

The height of the port is only changed if you want to change the revs which the power kicks in, the shape of the port is often changed if there is little width change that can be done.

 

The transfer timing is changed if the manufacturer may have left a bit on the table or the exhaust roof has changed shape to the degree less blow-down time is required.