I Ported my 346XP

[JSFGreig]

then I have definately over done it ive gone way further than 1mm thanks anyway and don't worry too much as the saw was given to me as a box of parts by a neighbour, I had a look over it and decided it wasn't worth the money rebuilding and buying new parts it needed so it was just a practice really! definately should have done a bit of research before I started but I will enjoy my new ashtray and don't worry I would never try it on a running saw without properly researching up on it.

[Megatron]

To be honest I would leave the squish as it is such that you don't have to worry about the changes in timing. You can always go back to it. Then you will know exactly what the porting has done and how much of an affect the lower squish has. I think you will find there are bigger gains to be had from the increased flow than the increased compression. Remember you want to leave the intake (and transfers) even but rough to promote atomisation whereas you want to smooth out the exhaust.

 

[spudulike]

To be honest I would leave the squish as it is such that you don't have to worry about the changes in timing. You can always go back to it. Then you will know exactly what the porting has done and how much of an affect the lower squish has. I think you will find there are bigger gains to be had from the increased flow than the increased compression. Remember you want to leave the intake (and transfers) even but rough to promote atomisation whereas you want to smooth out the exhaust.

 

 

Sounds about right - the lower edge of the intake will drop by the thickness reduction of the base gasket and that should increase intake duration, the upper edge of the exhaust port was taken up by the difference in gasket thickness to preserve original timing and hopefully the reduced squish will increase compression by 5-10psi after all a higher compression always pulls better then a well worn one.

 

I pollished the exhaust and left the intake port but didn't spend hours on them.

 

Didn't get round to taching it as I was up at Mallory Park watching the Build Base Championship - a couple of TZ250s showing 600 and 1000cc fours a thing or two:thumbup:

[Old WoodChip]

Spud, did you ever play around with Bantam 175's in your younger days? you could port them and a good learning curve. Kids these days dont know their born:lol:

[spudulike]

Flippin eck M8 - how old do you think I am:thumbup: In my days it was the Yamaha FS1E (Fissie) but never owned one appart from one I did up and never took a portig file to it - I was always more in to fourstrokes.

My brother had a BSA C15, Royal Enfield Bullet and a Triumph Trophy 6 - I just played with my Honda 400/4 - lovely little rice burner!

 

I still havent had time to tach the saw - just too busy but hope I can do it over the next week. Got a 15" bar and a full chisel chain on it now and it sounds great.

 

Have had problems with my compression gauge and am currently resolving them - it measures 165 on my new gauge but a saw thet did read 175 on my old gauge now reads 160 on the new one so estimate it at 180psi+ and feels like it. Should pull really well soon:thumbup:

[spudulike]

At long last, a video, compression is running at 175psi, I have tached it at around 14,600 - had a few problems in this area, the carb was metering a tad too much fuel but a tweak to the metering needle sorted that out.

 

It runs, revs and idles spot on - very loud, my wife could hear me tuning it up a mile away.....or so she says:001_rolleyes:

 

Need to cut some logs for the log store in a while so will do another video then but it sounds glorious:thumbup:

[ame=http://www.youtube.com/watch?v=scqsPvclNdw]Muffler Mod and Ported 14,600RPM.MOV - YouTube[/ame]

[spudulike]

Mmmmm - thought I may get one or two comments about the vid - or even my dodgy PPE:001_rolleyes:

[burrell_]

have u cut any wood with it yet spud

[ben lightfoot]

She sounds awesome just waiting on the wood cutting vid to see the true performance

[spudulike]

have u cut any wood with it yet spud

 

No not yet - out yesterday and now halfway through a MS200T rebuild for another member - just pressure checked it - 100%, and am reassembling it now - looking good and should run like a champ soon.

 

Will try and cut some wood over the next week or two - pretty busy as usual!