A lot of people who port a lot don't talk because most of it has already been said.
People like me just hack until they get something good. We're not experts, so what are we qualified to talk about?
There are good threads out there on porting 372. Some have good numbers. The loss of photos is a huge bummer, please post yours!
I think what Huskihl was saying was don't buy the 268 popup. You're just going to cut it off. That's what Trappermike said too. I think a normal 268 piston has enough on it to make a tall popup if you deck the cylinder.
If there is a known brand of BB 372 cylinder that has good plating, please post it. Not being able to reliably port AM cylinders is a disappointment to us all, so please name names! I can vouch for Meteor jugs having nice plating. Casting is sometimes worse than OEM and my meteor jugs have very aggressive chamfers on the ports. I don't believe Meteor makes a 52mm jug.
Related to the 52mm big bores, the OEM 51.4mm XPW cylinder is available for $150+ if you want a guaranteed quality cylinder, though they require a lot of grinding to perform. I don't know of a popup option for that jug (maybe Dominant) but I bet it's been done.
@mixxer a 50mm used oem jug can be ported very successfully to make a 372 pull a 28" through almost anything. If you're after torque and ease of operation 50mm OEM may be cheaper and more reliable ported. If a 372 isn't handling your trees a 390 is pretty great!
People like me just hack until they get something good. We're not experts, so what are we qualified to talk about?
There are good threads out there on porting 372. Some have good numbers. The loss of photos is a huge bummer, please post yours!
Interesting you would say that. The research and conversations I've had with people on the subject suggest the opposite. Bump in compression, added intake, and a lighter piston. I generally hear it'll make a strong saw without any port work done.
I personally have not done the 268 mod myself as of yet.
I think what Huskihl was saying was don't buy the 268 popup. You're just going to cut it off. That's what Trappermike said too. I think a normal 268 piston has enough on it to make a tall popup if you deck the cylinder.
If there is a known brand of BB 372 cylinder that has good plating, please post it. Not being able to reliably port AM cylinders is a disappointment to us all, so please name names! I can vouch for Meteor jugs having nice plating. Casting is sometimes worse than OEM and my meteor jugs have very aggressive chamfers on the ports. I don't believe Meteor makes a 52mm jug.
Related to the 52mm big bores, the OEM 51.4mm XPW cylinder is available for $150+ if you want a guaranteed quality cylinder, though they require a lot of grinding to perform. I don't know of a popup option for that jug (maybe Dominant) but I bet it's been done.
@mixxer a 50mm used oem jug can be ported very successfully to make a 372 pull a 28" through almost anything. If you're after torque and ease of operation 50mm OEM may be cheaper and more reliable ported. If a 372 isn't handling your trees a 390 is pretty great!