porting help!!!

[Grapple Man]

hi all,

my first post. :

i have been virtually living on this site for the past 6 months or so reading everything i could find about saw mods. i have officially tackled my first mod as of a couple nites ago. it is a husky 55. i understand there is much less to gain from an open transfer saw but it is one of our least treasured pieces so i thought i would start there. i am not quite ready to tie into the 372.

i first completed the muffler mod on this saw and after seeing the increase in response in power after carb adjustment i was officially hooked. so i have widened and raised the exhaust a bit. cleaned up the imperfections and polished nicely. lowered the intake and put a very lite polish on. i am planning on taking out the base gasket to increase the squish which was very wide.

my question is what exactly to do if anything to the transfers i have cleaned them up, but being somewhat inexperienced and having read how important the angles of the transfers are, i am a little nervous about widening them. on the 55 not sure if all open ports are the same, but they have a steep angle from the cylinder wall back down into the outside of the cylinder a very pinched area and to do much widening would most likely require this to be altered in some way. even with small dremel cutters it will be tough to get into this area to provide a nicely finished product.

i am a novice so would appreciate good descriptions, but i have endlessly abused the search function on here, so i am not attempting this blindly.
i have really enjoyed reading everything you guys write and it is nice to get to hear information from people who actually use the saws they are talking about. the dealers of this part of the country are not so well informed.

thanks in advance for any help you can afford me. i really appreciate it.:greenchainsaw:

 

[JT78]

I dont know much about transfers so I leave them alone because you can really screw a saw up if you dont do them just right.

 

[Grapple Man]

thanks i am kinda feeling the same.

 

[drmiller100]

you really have a great attitude about it all, and are on the right path.

(1)

do not ever grind the transfer that doesn't point the intake charge towards the intake side.

then, grind the transfer to increase charge towards the intake side.

learn about what is "normal" in other 2 strokes as far as port timing duration.

measure your own saw, and scratch your head about the discrepancy.

start grinding.

Refer to (1), and start reading.

 

[Grapple Man]

thank for the info

i did do some rough timing numbers of the saw, so i will begin comparing the numbers of other motors to increase my knowledge base.

thanks

 

[Four Paws]

i understand there is much less to gain from an open transfer saw

Open transfers make big gains - I am not convinced that there is ANY drawback to them. In fact, I have seen cylinders ported by the big timers of saw racing and some have transfer bridges cut out of the jug. If you look at some of the heavy hitters (Husky 372 and Dolmar 7900) their transfers feed from the base - pretty much just like open transfers, but with a thin cylinder wall in place seaparating the piston from the transfer port. The shape is nearly the same though.

Transfers can be tricky. If you don't have the right tools to do a good job, don't touch the roof of the transfer ports. As far as the rest of the port (lower portion - sides, back wall, bottom, etc.) accentuate the factory shape.

Good luck - building saws gets addictive once you realize some serious gains!

Josh

 

[troutfisher]

Open transfers make big gains - I am not convinced that there is ANY drawback to them. In fact, I have seen cylinders ported by the big timers of saw racing and some have transfer bridges cut out of the jug. If you look at some of the heavy hitters (Husky 372 and Dolmar 7900) their transfers feed from the base - pretty much just like open transfers, but with a thin cylinder wall in place seaparating the piston from the transfer port. The shape is nearly the same though.

Transfers can be tricky. If you don't have the right tools to do a good job, don't touch the roof of the transfer ports. As far as the rest of the port (lower portion - sides, back wall, bottom, etc.) accentuate the factory shape.

Good luck - building saws gets addictive once you realize some serious gains!

Josh

I think the closed transfer jugs tend to have a real deep transfer port, lots of "roof" to the port. I think that's what matters......I think when the charge comes out of the base, up the transfers, the roof of the port needs to catch it, turn it, and send it across the top of the piston toward the rear of the cylinder. It needs space to do that. The closed transfer cylinder just adds ring support. And removing it reduces friction. So, .....I agree.

 

[brncreeper]

Open transfers make big gains - I am not convinced that there is ANY drawback to them. In fact, I have seen cylinders ported by the big timers of saw racing and some have transfer bridges cut out of the jug. If you look at some of the heavy hitters (Husky 372 and Dolmar 7900) their transfers feed from the base - pretty much just like open transfers, but with a thin cylinder wall in place seaparating the piston from the transfer port. The shape is nearly the same though.

Transfers can be tricky. If you don't have the right tools to do a good job, don't touch the roof of the transfer ports. As far as the rest of the port (lower portion - sides, back wall, bottom, etc.) accentuate the factory shape.

Good luck - building saws gets addictive once you realize some serious gains!

Josh

How do you find a port's area? Do you use same method Jenning uses or is there an easier way?

 

[blsnelling]

Some good info here. My ears are open. On Stihl jugs, I taper the lower all the way to the base. Sometimes I also angle the upper transfer a little more towards the intake. Other than that, I don't do much to them. I don't want to ruin the jug with lack of knowledge and it's worked for me. I'm sure I'm leaving a lot on the table though. I just don't know enough about transfer porting to do much more.

 

[Tree Sling'r]

This what I do, obviously not finished. This is SILogger's jug.

 

[blsnelling]

This what I do, obviously not finished. This is SILogger's jug.

You definately opened that bad boy up! That's a lot more transfer work than I've ever attempted. I'm a little chicken on the transfers for some reason. I'm sure a lot of that has to do with the fact that you need a good right angle grinder to get in there and I don't have one.

 

[Four Paws]

This what I do, obviously not finished. This is SILogger's jug.

Lookin' good!

 

[Tree Sling'r]

You definately opened that bad boy up! That's a lot more transfer work than I've ever attempted. I'm a little chicken on the transfers for some reason. I'm sure a lot of that has to do with the fact that you need a good right angle grinder to get in there and I don't have one.

For sure. I have a CC Specialty right angle handpiece (90) for my Foredom and it makes upper transfer work a dream. That and obviously other tooling, special vises and lighting.
But, like I have stated, trial and error - big gains vs little gains it is a because of experimentation.

 

[forestryworks]

just curious - jasha, brad, fourpaws, how do you guys clean the little bits of metal from the jugs when you're done with the work?

sounds like a juvenile question, but...

 

[Tree Sling'r]

just curious - jasha, brad, fourpaws, how do you guys clean the little bits of metal from the jugs when you're done with the work?

sounds like a juvenile question, but...

Air, brush, hone then hot soap and water.

 

[056kid]

I want to do a test run on my old 288 jug, what is this 90 grinder thing, would sears... have one.
I can see that a demel will only reach the bottom and outside part of the transfers.

 

[brncreeper]

I want to do a test run on my old 288 jug, what is this 90 grinder thing, would sears... have one.
I can see that a demel will only reach the bottom and outside part of the transfers.

You mean this?

 

[Grapple Man]

Open transfers make big gains - I am not convinced that there is ANY drawback to them. In fact, I have seen cylinders ported by the big timers of saw racing and some have transfer bridges cut out of the jug. If you look at some of the heavy hitters (Husky 372 and Dolmar 7900) their transfers feed from the base - pretty much just like open transfers, but with a thin cylinder wall in place seaparating the piston from the transfer port. The shape is nearly the same though.

Transfers can be tricky. If you don't have the right tools to do a good job, don't touch the roof of the transfer ports. As far as the rest of the port (lower portion - sides, back wall, bottom, etc.) accentuate the factory shape.

Good luck - building saws gets addictive once you realize some serious gains!

Josh

you guys are great. i really appreciate everything you offered to me for advice. i followed and the saw is back together and running freaking great. i just posted a thread about my new RPM's looking forward to what i am going to learn today.
thanks again. i am definitely addicted. looking at our 372 already!!! :greenchainsaw:

 

[blsnelling]

Air, brush, hone then hot soap and water.

+1. All of the above.