Spuds Porting and Tuning Thread

[wisewood]

I would retune both but it is only the H screw that may cause damage. I would just tach the saw to 13000 - 13500 rpm, without a tach, give the H screw a 1/4 turn anti clockwise and check the plug colour after an hours running - it should be coffee colour!

 

I would be concerned about just putting on a dual port without any retune!

 

Hi Steve,

Got the saw tached just under 13000

But both H and L screws are between 3/4 to 1 turn out so less than factory settings.

Does this sound ok?

New plug only put one tank in and checked.

Will take another look after next tank.

Cheers, Si

[spudulike]

The plug looks a bit light but also hasn't gained much colour yet. If it is tached to 13000rpm, all should be fine.

[wisewood]

The plug looks a bit light but also hasn't gained much colour yet. If it is tached to 13000rpm, all should be fine.

 

Good to hear mate, thanks a lot 👍

I'll keep checking the plug for now.

[jamallio96]

How much difference do you reckon a muffler mod and retune would make to a Husky 445, and would it be worth it?

[spudulike]

How much difference do you reckon a muffler mod and retune would make to a Husky 445, and would it be worth it?

 

A muffler mod would be the simple way to go as the engine is a clam shell type so it makes porting more difficult and gives less options.

[jamallio96]

A muffler mod would be the simple way to go as the engine is a clam shell type so it makes porting more difficult and gives less options.

Aye, but would it make a noticeable difference to the saws performance, or is it not worth it on a small-ish semi-pro saw?

[spudulike]

Aye, but would it make a noticeable difference to the saws performance, or is it not worth it on a small-ish semi-pro saw?

 

Probably not worth your while paying to have it on my bench but if you can do it yourself, it would be worth it.

[Lazurus]

A muffler mod would be the simple way to go as the engine is a clam shell type so it makes porting more difficult and gives less options.

 

Sorry to hi jack the thread Spud, but can you explain a "muffler mod" I hear about it a lot but don't know exactly what it is. Is it similar to exhaust tuning on IC engines for better breathing etc.?

 

S.

[spudulike]

Sorry to hi jack the thread Spud, but can you explain a "muffler mod" I hear about it a lot but don't know exactly what it is. Is it similar to exhaust tuning on IC engines for better breathing etc.?

 

S.

 

All you doing with a muffler mod is getting the exhaust gasses out of the engine a bit quicker by opening up the outlet hole and modifying the baffle plate if present. The exhaust inlet can be matched to the exhaust port in some cases.

 

The muffler mod shouldn't be confused with a "Tuned Pipe" or expansion chamber, these use a tuned chamber to reverberate the exhaust pulse back in to the engine to develop more power and changed power band.

[Lazurus]

All you doing with a muffler mod is getting the exhaust gasses out of the engine a bit quicker by opening up the outlet hole and modifying the baffle plate if present. The exhaust inlet can be matched to the exhaust port in some cases.

 

The muffler mod shouldn't be confused with a "Tuned Pipe" or expansion chamber, these use a tuned chamber to reverberate the exhaust pulse back in to the engine to develop more power and changed power band.

 

This guy is good!