288 Big Bore

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A 288 with a 394 top end. Yes I have already done one. Seems like a cinch at first but it is not. Measure the distance between the crank center line and the deck on the 288. Now measure the same on the 394, big difference. This big difference is expressed in the port timing and ability to get any compression.
I did it and you can too but know this, it is not a bolt together project. Machining is neccessary. Mike (same guy that did "heart of a lion")

I was really hopeing you would come on and give me some serious direction. I haven't had alot of time recently but at least I know what to look at, I was afraid there would be some differences in deck heights, it's not only improtant to share the same stroke, but it also matters where your cylinder base is positioned along that stroke. Im gonna have to do some home work and see what I am up against, again Thanks for showin' up and adding what you know I'm gonna need it. Im still undecided about doing it, but we'll see.
 
Sold 288

I got on with Unit Drilling and in order to make the trip to Casper I was forced to sale the 288, broke my heart that was my favorite saw! I guess that is the difference between men and boys, being willing to sacrafice for the greater good of the family. On the positive side the job is great and going well, and I am making enough that there is another saw already in the future.
 
395 stroke

THAT WAS A AWESOME THREAD!!!! THANK YOU! I don't deal in a lot of hard woods, around here we get alot of cottonwood, locust, and Chinese elm, mostly nusance trees people want removed. They are usually huge, and have a ton of nail, and other assorted iron matter in them from either nailing the old fence to them or Little Jonny and his Buddy's trying to build a tree house in them. The worst and nastiest among them has to be willow, hard as a rock, and the wood tends to heave closed behind your bar, and will literally lock your bar and chain in the tree. I hate the stuff, and have seen more then one 372 go to saw heaven, because of this. Overheat the saw so bad the main bearings sieze, a determined and stupid lot who think the 372 is invincible. I have made good money cutting willow, but I have never approached one with anything smaller then my 288, and I always bring two saws, run one while the other cools.
I was just looking to give my 288 a little more grunt, but It is a winder too, and while I like strokers(gives me a idea of what to do with all the 2100 parts I got laying around) I was just looking to get a little more with a simple piston and cylinder change, I am really beginning to think the best way to go would be to use a 395 cylinder, and rig up a cable throttle set up, I hear the 395 has improved transfers that will help keep top end, problem is the 395 also uses I think a 42 mm stroke, I THINK. This is why I am here to find someone who has really built this kind of thing, I want it to say 288 on the side, and run with the big, big boys!

The stroke on the 395 is 38 mm, The intake is round and won't fit the plastic manifold on a 288.
 
The stroke on the 395 is 38 mm, The intake is round and won't fit the plastic manifold on a 288.

Figured all this out by yourself did you? That was the point the swap has been done. The question was how was it done? Further what was need to complete the swapp the intake is no issue use a 394 cylinder to begin with hard to find but solves a few issues. The 394 uses a intake similar to the 288, or you could figure out how to reroute the impulse line and use a 395 cylinder and intake and fab up a throttle and choke linkage. No the real issue with the swap as I understand it came in the deck height are radically different I know this was over come but I am not sure how it was done. Hopefully who ever it was would be kind enough to shed some light here.
 
Waste of time and money.

Figured all this out by yourself did you? That was the point the swap has been done. The question was how was it done? Further what was need to complete the swapp the intake is no issue use a 394 cylinder to begin with hard to find but solves a few issues. The 394 uses a intake similar to the 288, or you could figure out how to reroute the impulse line and use a 395 cylinder and intake and fab up a throttle and choke linkage. No the real issue with the swap as I understand it came in the deck height are radically different I know this was over come but I am not sure how it was done. Hopefully who ever it was would be kind enough to shed some light here.

Messing around with old parts is a waste of time unless you get enjoyment out of it. The most efficient way to have a great saw is to buy a ported 390 from Madson's.
 
Messing around with old parts is a waste of time unless you get enjoyment out of it. The most efficient way to have a great saw is to buy a ported 390 from Madson's.

How is it a waste of time? We do this type of stuff because we DO enjoy it. If a little cutting, grinding, tinkering and tweeking can increase power then why not? Plus a good portion of us don't have the $ to go blow $1400 on a new ported 390. Madson's would also be my bottom of the barrel choice to get a new ported saw. I would rather give my money to a arborist site sponsor that I can personally get to know.

Terry it seems like rupedoggy is the only one that we know has done this. He is still active here with his last login being yesterday. Maybe just maybe he can shed some more light on just how much difference there is. If he remembers.
 
I've bought a lot of stuff from Madsens including saws but there's better places to get ported saws out west and in the east. I prefer doing my own port work any way.
 
I am really beginning to think the best way to go would be to use a 395 cylinder, and rig up a cable throttle set up, I hear the 395 has improved transfers that will help keep top end, problem is the 395 also uses I think a 42 mm stroke, I THINK. This is why I am here to find someone who has really built this kind of thing, I want it to say 288 on the side, and run with the big, big boys!

As far as I know the 394 and 395 have the same bore and stroke, 56mmx38mm. Their cases are the same. Check the part numbers. So they bolt up. When rebuilding a 394 one has the option of using a 395 top end. You have to change the intake side, between carb and cylinder, because the 395 uses an impulse hose instead of internal passage but the throttle cable works. The extra parts cost about $60. Don't know how you would adapt the 288 throttle linkage. Might be simpler to use the 394 cylinder.
 
You need a milling maching and a lathe. You need tools that will give you exact readings. You need knowledge of port timing and squish. You need a degree wheel. You need a 394 piston and a 395 cylinder. Then the boot from a stihl 084 cut in half and a HT1 carb. Put the throttle from a 50 husky on the handle and fab up some linkage for the throttle rod. The muffler from the 288 will work but that takes a little fabrication work too. The top cover requires extensive modification and a relocate on the plug wire. That's what I remember off the top of my head. There are probably other things as well. If all this does not make you come to your senses then go ahead and do it, or come over and get mine and run it and see what you will possibly end with. I will also trade you mine for something else that way you won't have to go through all the things I did. It is not easy or everyone would have done it by now, and what do you end up with? A light weight 395 that looks like a 281. Mike
 
Messing around with old parts is a waste of time unless you get enjoyment out of it. The most efficient way to have a great saw is to buy a ported 390 from Madson's.

You remind me of a saying I once heard it was told to me as advice I am gonna pass it to you as advice, "It is better to stand in silence in a crowd and make people wonder if you are a fool then to open your mouth and remove all doubt." There are hunderds of years of combined knowledge and experience here on this sight, I am here to learn from that. I don't like every thread or agree with everything posted, but people have a right to there opinions, and I have a obligation to them to respect their right to their opinion and there thoughts, besides what business is it of yours what I do in my spare time, you don't like the thread then please feel free to leave it and allow those of us with interest in it to go peacefully about our business.
 
Hello Mike Good to see you still hanging out, and thanks for reminding me why I kinda gave up on this idea, I don't have the mill Or lathe(yet), and I think your right some ideas seem like winners when in reality, you are better off leaving the 288 for what it is a 85cc bad boy, and if you want more just go out and get a 395. I still kick semi stupid ideas around and then if I am thinking about it enough I bring the idea here just so someone with logic, can set me straight thanks.
 
You need a milling maching and a lathe. You need tools that will give you exact readings. You need knowledge of port timing and squish. You need a degree wheel. You need a 394 piston and a 395 cylinder. Then the boot from a stihl 084 cut in half and a HT1 carb. Put the throttle from a 50 husky on the handle and fab up some linkage for the throttle rod. The muffler from the 288 will work but that takes a little fabrication work too. The top cover requires extensive modification and a relocate on the plug wire. That's what I remember off the top of my head. There are probably other things as well. If all this does not make you come to your senses then go ahead and do it, or come over and get mine and run it and see what you will possibly end with. I will also trade you mine for something else that way you won't have to go through all the things I did. It is not easy or everyone would have done it by now, and what do you end up with? A light weight 395 that looks like a 281. Mike
Still got it? I’d like to do one. Have a GTG coming up in Placerville…
 
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