Spuds Porting and Tuning Thread

[jnoon]

Nice vid Josh, pretty much bang on 20 seconds per saw - pretty impressive a 50cc saw keeping up with a 70cc one:thumbup:

 

 

I timed it at 20 secs per saw both full chiz hand sharpened very impressed mate, can you do the 372 when you get time 👍

[spudulike]

Ive not read the whole thread but have scanned through so apologies if this has already been raised.

how would a potential insurance claim be effected if a wee balls up occurred whilst using a modded saw.

would you have to tell the insurers like if you were driving a modded XR2?

i dont remember there being a 'using a modified saw' section in my insurance application

 

From my side, I do point out that if the saw is to be used by employees then a modded saw would probably not be suitable down to the H&S if there were an accident, but for your own use, it is your own personal choice.

 

I had a motorbike tuned once - the choice was mine - the tuning shop just did what I asked of them!

 

I am NOT taking H&S lightly, I see many machines come in with chain catchers missing or damaged chainbrake handles used by pro users........which get repaired:001_rolleyes:

[spudulike]

I timed it at 20 secs per saw both full chiz hand sharpened very impressed mate, can you do the 372 when you get time 👍

 

You are on the list with the 372XT- thanks for the vid, I rarely get to time, compare and use many of the saws I do so having comparisons like this, teally help:thumbup: Sounds like it is pulling good revs through the cut!

[jnoon]

You are on the list with the 372XT- thanks for the vid, I rarely get to time, compare and use many of the saws I do so having comparisons like this, teally help:thumbup: Sounds like it is

pulling good revs through the cut!

 

 

 

Yes it does very well, I lifted the saw near the end of the cut and you can hear it four stroking lovely

[wyk]

So here's sumfin completely different. This is my carving saw. A bud of mine got an Echo 330EVL about 8 months ago and put up a thread on AS repairing and porting it start to finish. I took interest as I needed a tiny saw for detail work on furniture. When one came my way for dirt cheap, I jumped on it. Since I only needed it for carving, I didn't bother porting it. I didn't even bother removing the lower gasket. Still, after seeing his vids and the lackluster stock performance, I did have to make a couple of mods. I spent a solid hour and a half gutting the muffler, and smoothing the intake passages and exhaust gaskets. I then advanced the timing nearly 50% of the key. This turned out to be too much at first since Echo was using some pretty aggressive timing to start, and got me detonation after a few long cuts. I set her back to about 25% of the key and she's much happier now. For a lil 33cc saw with a 14" bar, she has a load of torque. This is her in some very hard seasoned beech with straight out of the box Oregon 91VXL chain, which turned out to be pretty grabby in this wood:

 

https://www.youtube.com/watch?v=AYWoIr9xzlU

[wyk]

Some folks have asked me if I could explain what a saw does when it detonates. I happened to have caught it on video. Since this is a lil cheaper ECHO, I decided to run it a bit and show folks what to expect with severe detonation on a saw since I had little to lose.

 

[spudulike]

Some folks have asked me if I could explain what a saw does when it detonates. I happened to have caught it on video. Since this is a lil cheaper ECHO, I decided to run it a bit and show folks what to expect with severe detonation on a saw since I had little to lose.

 

 

And if left will end up with a piston crown that looks like the surface of the moon:thumbdown:

 

Only had it in on one saw and that was the 066 when I was messing around with ignition timing - the only time you are likely to get pre ignition or detonation.

 

The 066 just didn't rev right and sounded like it was about to blow so switched it off quickly!

[spudulike]

Started porting a 357XP, put the timing wheel on it and got some surprising figures - never pulled the figures from one of these saws before -

 

Exhaust port Duration - 148*

Transfer Duration - 122*

Inlet duration - 144*

Blowdown - 13*

 

Interesting figures, I am guessing Husqvarna developed this saw to work on high crankcase pressure and have a very short blowdown period - there is a lot that can be done to the ports as the piston is "Non windowed" so the ports can be widened a lot:thumbup:

[Acg128]

Big thanks again Steve for porting my saw while I waited yesterday! Got a bearing on route so will let you know how I get on. Top bloke, nice one bud.

[spudulike]

Big thanks again Steve for porting my saw while I waited yesterday! Got a bearing on route so will let you know how I get on. Top bloke, nice one bud.

 

No worries, a pleasure to help and hope you get the bearing sorted soon:thumbup: