High Quality Chainsaw Bars Husqvarna Toys Hockfire Saws

Preparing to port first saw - which one, and what method?

MG porting

Pinnacle OPE Member
Local time
9:38 PM
User ID
6543
Joined
Jun 28, 2018
Messages
2,491
Reaction score
7,105
Location
Wa
Country flag
Ok, my wife was out of town and I had time, so I ported my older 266 last night. It had the SE Mahle cylinder on it, labeled 50ZN11. I had an extra XP cylinder (50ZN13), so I decided to do that one.

Without base gasket, the numbers for the XP cylinder were:
Exhaust: 106
Uppers: 122
Intake: 70
Squish: .017"

I took down the ridges on the lower transfers and smoothed them out, being careful not to go deep towards the case. I removed some material inside the transfers behind the "bridge" to skinny them up as well.

Raised exhaust roof slightly to 102, really widened it up and funnelled it outwards. Exhaust roof was pretty flat from the factory, so I followed the factory contour. Polished everything up very nicely afterwards with aluminum oxide stone, then emery paper in a mandrel, then polishing compound and a felt wheel. Port matched muffler and gasket. Muffler was already modded.

Lowered intake to 78, widened, and cleaned up. Left it rough.

Went over edges with diamond ball, and then ball honed both directions.

Advanced timing 0.025" off the key.

Now it's sitting at:
Exhaust: 102
Uppers: 122
Intake: 78
Squish: .017"

I heat cycled it a couple of times, and then put it in the wood this morning. Pulled a 25" full comp with low rakers in some 20" green pine with way more power than before. Throttle response is way better. Tunes at WOT @13.2k. Holds 9.5k in the cut. Sounds great.

I'm happy. I used the full-circle piston that was in it, but I think I will tear it down and replace it with the windowed Meteor piston sometime in the near future. I'll share some pics then.

I think I will use this recipe for the 266 build that I am working on in the other thread.
I would leave the full circle piston in it but that's just me glad it worked out for you tho now you'll be finding saw to port just because 😆
 

mainer_in_ak

Pinnacle OPE Member
Yearly GoldMember
Local time
8:38 PM
User ID
22880
Joined
Mar 13, 2022
Messages
581
Reaction score
2,366
Location
Interior Alaska
Country flag
Dang, nice work! You chose the right saw to port. The older dual port 67 cc saws are dirt cheap, and when woods ported at home, slap all of the current 60 cc saws silly. Parts are cheap and readily available.

I too started porting on the older 67 cc saws, and they sing a sweet song! They out-cut my stock jonsered 2172 and the neighbors stock stihl 044.

The 67 cc saws were 1/4 the price of my more modern 70 cc saws. Old, cheap woods ported 67 cc saws actually resulted in me quitting 40-50 cc saws. Gave em all away.

Never heavy in weight, and ideal for everyday cutting and most typical wood. Most smiles per dollar.
 
Last edited:

mainer_in_ak

Pinnacle OPE Member
Yearly GoldMember
Local time
8:38 PM
User ID
22880
Joined
Mar 13, 2022
Messages
581
Reaction score
2,366
Location
Interior Alaska
Country flag
Ok, my wife was out of town and I had time, so I ported my older 266 last night. It had the SE Mahle cylinder on it, labeled 50ZN11. I had an extra XP cylinder (50ZN13), so I decided to do that one.

Without base gasket, the numbers for the XP cylinder were:
Exhaust: 106
Uppers: 122
Intake: 70
Squish: .017"

I took down the ridges on the lower transfers and smoothed them out, being careful not to go deep towards the case. I removed some material inside the transfers behind the "bridge" to skinny them up as well.

Raised exhaust roof slightly to 102, really widened it up and funnelled it outwards. Exhaust roof was pretty flat from the factory, so I followed the factory contour. Polished everything up very nicely afterwards

Advanced timing 0.025" off the key.

Now it's sitting at:
Exhaust: 102
Uppers: 122
Intake: 78
Squish: .017"

Pulled a 25" full comp with low rakers in some 20" green pine with way more power than before. Throttle response is way better. Tunes at WOT @13.2k. Holds 9.5k in the cut. Sounds great.

9500 rpms in pine is a bit slow. Check the compression, that squish is a bit tight and might be fighting yah.

Pull the cylinder and raise the exuahst roof a couple more degrees. Should gain some rpms in the cut.
 

huskihl

Muh fingers look really big
GoldMember
Local time
12:38 AM
User ID
360
Joined
Dec 31, 2015
Messages
23,032
Reaction score
147,036
Location
East Jordan, MI
Country flag
9500 rpms in pine is a bit slow. Check the compression, that squish is a bit tight and might be fighting yah.

Pull the cylinder and raise the exuahst roof a couple more degrees. Should gain some rpms in the cut.
It needs the transfers raised 4° in order to get those RPMs back.
 

huskihl

Muh fingers look really big
GoldMember
Local time
12:38 AM
User ID
360
Joined
Dec 31, 2015
Messages
23,032
Reaction score
147,036
Location
East Jordan, MI
Country flag
Stacking cutting disks OK?

I think everybody that has ever ported a saw has done it once or twice. I have cut the line I wanted and then smoothed it out with a round ball in a straight hand piece. Just be careful of the plating next to the port
 
Top