Porting - Performance Measured?

[Eddy_t]

To answer your questions, no, porting does not benefit the saw in the long run, by increasing compression, mixture intake and speed, you get more bang for your buck but it puts more strain and wear on components (mainly bearings) and the more power you gain, the more the wear. The actual % many of the porters give is actually the % decrease in cut time, not the actual gain in power, after all, a 40% power gain on a saw would be quite immense when you think about it


Sent from my iPhone using Tapatalk

 

[moody]

To answer your questions, no, porting does not benefit the saw in the long run, by increasing compression, mixture intake and speed, you get more bang for your buck but it puts more strain and wear on components (mainly bearings) and the more power you gain, the more the wear. The actual % many of the porters give is actually the % decrease in cut time, not the actual gain in power, after all, a 40% power gain on a saw would be quite immense when you think about it


Sent from my iPhone using Tapatalk

Can you show proof of this?

Sent from my SM-N900V using Tapatalk

 

[moody]

Why can't we get traffic like this more often? It take 1 person to step in and fuel conversation. There was a day when this wouldn't have been a problem. Nowadays guys don't seem to hash out information or otherwise educated opinions without being provoked.

Sent from my SM-N900V using Tapatalk

 

[HuskStihl]

Unlike all other internal combustion engines, increasing the performance of chainsaws generally results in less heat, increased longevity, and better efficiency. That's why all my XP saws are ported

 

[Moparmyway]

I do think you have some assumptions built into that comment

Obviously I made those numbers up

I did state that you would "port and tune it properly" ................. obviousely the "blue goo wonder kid" port job wouldnt be a good example to use in any comparison !

Hmmnnn ............... no assumptions on anything I stated, just real world facts from actual use of my own ported saws !!

HOWEVER .............. YOU stating that I made assumptions, then YOU making up numbers takes the cake ................... my hat is off to you - they have streets in NYC named after you .......... "ONE WAY"

 

[Chris-PA]

I did state that you would "port and tune it properly" ................. obviousely the "blue goo wonder kid" port job wouldnt be a good example to use in any comparison !

Hmmnnn ............... no assumptions on anything I stated, just real world facts from actual use of my own ported saws !!

HOWEVER .............. YOU stating that I made assumptions, then YOU making up numbers takes the cake ................... my hat is off to you - they have streets in NYC named after you .......... "ONE WAY"

Wow, I really have no idea why you've got your panties in a twist. My comments were intended as part of a conversation, not an attack on you. This seems to be typical of the way all threads go around here any more. Everyone approaches a polite disagreement as if someone threatened their manhood or insulted their mother.

I dunno, in spite of some really good people here this place is getting more difficult to take - too much noise, not enough signal.

 

[mdavlee]

Chad are you taking the dyno to the PA gtg? I might send a saw up there to be run on the dyno if it's possible. I think a bunch of people need to send saws and have a dyno day like with trucks and stuff.

 

[troylee]

I grew up in Colfax IL, which was the home of A&W dynometer. Every year they would have a dyno day, and all the farmers would bring in their tractors and burn some coal. This not only gave the guys something to brag about, but got A&W caught up with their run time on each unit, before it left the plant. Tractors were hooked up thru their PTO, but they also make chassis dyno's for semi's also.

 

[treesmith]

Yesterday I sectioned down a fat gum stem with my Randymind 660 on spikes.
It is an absolute machine, yeah it drinks fuel but it eats wood faster. When I compare it to my stock 288xp it's obvious it uses fuel quicker but it will also run a foot longer bar easily, cut more wood and has much bigger balls.
Love my 288 though

Sent from my GT-I9210T using Tapatalk

 

[CR888]

l enjoy threads like this and its amazing what can be put on the table by members around the globe from many trades, proffesions and backgrounds of vast experience. We all need to not take things so seriously or personally and do our best not to defame, insult or act in a derogatory manner to our fellow members. What brings allmost all of us here is our passion for saws, not our ability to be rude or pick fights. l'm sure we can disagree, debate and hash things out for not only our benefit, but the collective membership as a whole. With all the talent amoung our members lets do our best to allow everyone to participate without fear of being disgraced.

 

[Moparmyway]

Wow, I really have no idea why .

Your comments arent exactely coming across the right way then ................
1. When you twist what was stated and run with it, it tends to turn up the heat.
2. When you brush off others comments or experiences as "assumptions" - then use made up numbers in your own post .................. it looks like you are asking for trouble

 

[Eddy_t]

Can you show proof of this?

Sent from my SM-N900V using Tapatalk

Could you show otherwise?
No I cannot prove it shortens the life as I don't have a ported and stock model of the same saw to run together until one dies. But basic mechanical science will dictate the ported saw wears out first due to higher speeds and compression putting more strain on bearings, amongst other stuff. An increase from 150psi to 200 is 1/3 more strain, whilst an increase of 1000rpm is going to increase bearing temperature, reguardless if the actual cylinder is cooler, those parts are steel and don't transfer heat as well as aluminium


Sent from my iPhone using Tapatalk

 

[one.man.band]

"no quarter"

-omb

 

[one.man.band]

drag race vs. tractor pull

-omb

 

[one.man.band]

putting 40% more on top of a piston is huge.

-omb

 

[one.man.band]

web search:

dynamic bearing loads and life - skf

loads - skf

some bearing load and service life calulators there as well for those inclined.

have not heard of any saws getting into 'detonation' shock loading conditions, but guess it may be an outside possibility.

enjoy the day folks.

-omb

 

[chadihman]

Chadiham,

You said on the first page you put your porteds to wood first, then on the dyno. What are you looking for in your dyno numbers, and from whence are these derived? Do you finish your work based on the wood or the dyno? Guess I'm just confused, first as to why you'd begin in the wood at all, then as to how you know your dyno readings are where you want them. And do you take pre-port stock dyno readings for a baseline?

As for the only real question I posted here, I guess there's no evidence to show that porting benefits the saw health-/longevity-wise?

Guess I'm also wondering whether the dynamics of a single piston two-stroke are sufficient to warrant a dyno that seems better suited to more sophisticated engines.

I built the dyno about a year ago. I was off work for 6 weeks and light duty work for another 6 weeks. It was during this time in my absolute boredom I did lots of thinking. I planned out my dyno and started ordering parts. I couldn't get to work to build the heavy dyno so I worked on saws in my garage very gingerly. I ported quite a few and my brother helped me with timed cuts. I then recovered and started assembling the dyno. I dyno tested my ported saws and tested them against stock saws. I have not ported any saws since then but I have done lots of fuel, air filter, muffler mod and timing advance tests. I just don't have time to port saws anymore and the dyno has been sitting a while also. I had big plans for before and after porting runs. I wanted to test every little change in port timing and test after each mod but I just didn't have the time. Two young kids and work keep me busy. I can't wait till Randy gets this dyno as I think he will make very good use of it. It just may take porting to the next level. I almost forgot to tell you that I always test a base line saw against the saw that gets mod testing. This gives me accurate #'s every time. It doesn't matter the HP of the base saw its just there to compare #'s against. If my base saw has 3 HP at 9000 rpms and my mod saw has 6 HP at 9000 rpms its 100% stronger. I then zero the #'s and make a mod change. I test both saws again and compare the #'s. Very easy to see a gain or loss that's accurate. I test at rpms from 6000- 11000 in 500 rpm increments and record torque and HP at every 500 rpms.

 

[moody]

Could you show otherwise?
No I cannot prove it shortens the life as I don't have a ported and stock model of the same saw to run together until one dies. But basic mechanical science will dictate the ported saw wears out first due to higher speeds and compression putting more strain on bearings, amongst other stuff. An increase from 150psi to 200 is 1/3 more strain, whilst an increase of 1000rpm is going to increase bearing temperature, reguardless if the actual cylinder is cooler, those parts are steel and don't transfer heat as well as aluminium


Sent from my iPhone using Tapatalk

Basic 2 stroke knowledge more fuel better lubrication. Better lubrication means less heat. When you increase flow you evacuate heat faster. What makes you think that every saw has 200 psi?

Sent from my SM-N900V using Tapatalk

 

[Chris-PA]

Your comments arent exactely coming across the right way then ................
1. When you twist what was stated and run with it, it tends to turn up the heat.
2. When you brush off others comments or experiences as "assumptions" - then use made up numbers in your own post .................. it looks like you are asking for trouble

What did I twist? The word "assumption" is not a negative, it is how we reason things out, it is the ideas hidden inside the statements you made. All these theories are sets of assumptions and the conclusion may not hold if the assumptions change. What I did is to re-state what you wrote in a different way in the hope that it would lead to better understanding. That was not an attack on you, just a discussion of the ideas.

That a saw puts out more power does not mean it is more efficient. Perhaps in a world where all pros use saws with "proper" ports jobs - meaning that they are at least equally efficient as wen they were stock - then ported saws always are more effective. But there are many people porting saws, few using any of the techniques and tools available to the groups that designed them, and I'm betting the results vary a lot. Just reading here will confirm that. Some guys go for rpm, some go for a wider powerband.

In turn, those terms - efficiency, fuel consumption, hp/torque curves are things that can be measured on a dyno, although an experienced person can determine some of it by feel (fuel consumption needs to be measured).

 

[CR888]

l have never been to Masdens saw shop but l believe they have been servicing loggers for many years. l also believe but may be wrong that they used to build competition race saws and had some pretty clever qualified techs. They believe a dyno is the best testing device for modified and stock saws. Just thought l'd through this info into the thread. l suppose it would be very impractical to go outside and cut a cookie and have another qualified tech standing there with a stopwatch everytime they wanted to varify/test a saw.lol. They would have lots of cookies if they did & have a very well rehersed stopwatch man with very saw fingers. l think the cookie test can give you a rough idea of whats going on but when being paid to build competition winning saws, l understand why they have a dyno.