Frank Savage
ArboristSite Operative
I have some noname 50mm topend to play with and I´m wondering about this:
To make the Aux transfers opening a wee bit before the mains. To get more uniform wash of the chamber with maybe less washout of the fresh mix. Maybe even with a realy slight sloping top, to open the utmost rear corner first.
I did a real torque monster before, with fingerports, capable of cutting through nails, wire ropes and fences in the wood with no indication in the sound or revs (only chain dulled and chipping pieces of teeth were flying off). But it had only a very narrow powerband, was a real gas guzzler and quite useless dog outside the optimal rev range. So quickly I went back to only slightly modded factory topend setup.
I don´t want to get the same result as with the fingerports. Preferably rise the power by some 10-12%, boost the mileage a bit and to get as little fresh mix washout as possible-for occasions when I work with the saw up in the tree, just in front of my nose.
The timing will be like In 80°, Ex 100°, Transfers around 120°, Blowdown 22-23°. Probably a slight shelf in the exhaust, shooting for like 0,015-0,018 squish.
Experiences, coments, ideas?
To make the Aux transfers opening a wee bit before the mains. To get more uniform wash of the chamber with maybe less washout of the fresh mix. Maybe even with a realy slight sloping top, to open the utmost rear corner first.
I did a real torque monster before, with fingerports, capable of cutting through nails, wire ropes and fences in the wood with no indication in the sound or revs (only chain dulled and chipping pieces of teeth were flying off). But it had only a very narrow powerband, was a real gas guzzler and quite useless dog outside the optimal rev range. So quickly I went back to only slightly modded factory topend setup.
I don´t want to get the same result as with the fingerports. Preferably rise the power by some 10-12%, boost the mileage a bit and to get as little fresh mix washout as possible-for occasions when I work with the saw up in the tree, just in front of my nose.
The timing will be like In 80°, Ex 100°, Transfers around 120°, Blowdown 22-23°. Probably a slight shelf in the exhaust, shooting for like 0,015-0,018 squish.
Experiences, coments, ideas?