Stihl 026 Stock / Ported Comparison Pics

[wyk]

Wow, you weren't kidding about the clean part. Nice work! You gonna send me an image of the PSI?

 

[pops21]

How do you do the transfer work? Will a dremel fit, or do you have a 90 degree one.
Perfect timing, I am doing an 026 now as a gift and will port it. I have never messed with transfers before.
and if all works well, I will do my old 026 the same way later.

Transfers can be done with a dremel but boy oh boy is it HARD to make perfect. 90 degree tool is where its at for transfer work.

 

[Mastermind]

I have some angled handpieces but use a cutoff wheel in the 026 for the uppers, I do then blend it out smooth with a rt angle handpiece and a burr.

Sorry Wes, this saw killed my tester a bit ago. It would be at 190psi or so though.

 

[kevin j]

forgot to ask: what fuel line & filter fit. Have to change them anyway, may as well upsize.
and +1 on the 'what carb mods' question.

Might be time to look into the 90d tools.

 

[Log Hogger]

I've found that raising the upper transfers a few degrees with other mods allows an engine to hold the rpm in the cut. The higher the exhaust and transfers go in relation to each other the high the rpm seems to go. I'm sure that there's a point when it starts going the other way though. Too much exhaust without the compression to support it and an engine is just a screamer that has no useable torque.

So would it be correct to say that maintaining the same blowdown by raising the exhaust and transfers together will produce gains in both rpms and torque, up until the point that the height of the exhaust lowers compression too much?

 

[DSS]

I knew I shoulda kept that damn saw....:biggrin:

 

[parrisw]

So would it be correct to say that maintaining the same blowdown by raising the exhaust and transfers together will produce gains in both rpms and torque, up until the point that the height of the exhaust lowers compression too much?

Sorta ya. Just don't go raising things too high. The transfer timing can have a fine line, its not hard to go too far.

you know you raised the ex too high when you reach the squish band.:hmm3grin2orange:

 

[woodyman]

Very nice reading,thanks.I have a free straight gassed 026 on my bench which I will be porting in a month or so.I will just be widening the intake and exhaust ports,opening up the muffler and no base gasket.I do all my porting now with hand files and wet/dry sandpaper.The first saw I ported was an 026 heres a pic of the ports(don't laugh too hard).

 

[Mastermind]

forgot to ask: what fuel line & filter fit. Have to change them anyway, may as well upsize.
and +1 on the 'what carb mods' question.

Might be time to look into the 90d tools.

This is a upgrade line for the 026. I used the one for the MS260, Stihl part #1121 358 7700
MS660 fuel pickup body, # 0000 350 3504

I'm waiting on a carb....but it will be a wt194 with thinned throttle shafts and polished bore. I hate the see these saws butchered up and the 044 carb swap, while a powerful way to go ends up making the saw hard to use daily. I would love to find a carb that swaps well and uses a filter in the box properly. So far I've not.

So would it be correct to say that maintaining the same blowdown by raising the exhaust and transfers together will produce gains in both rpms and torque, up until the point that the height of the exhaust lowers compression too much?

The transfers are where you can ruin a saw or make one that is great. The exhaust on this saw is at 98°...that's pretty high for a stock jug, and will allow this engine to rev high. I raised the transfer port on an angle (higher on the intake side) to 116° At one time I would have never tried to go so high. For one thing.....since they are angled they open progressively, not all the way open at 116°. We have Brad Snelling to thank for sharing this one with me.

This will not work on every engine BTW, modding a two-stroke is not a one size fits all thing in the least. This saw has much more compression than a stock saw, plus all the other mods. I know the 026 fairly well, I've done 8 or 10 and am starting to get an idea what they like.

The intake timing is at 78°, in my experience with the 026 any more and you start losing case pressure, and just causes more spit back......at least in the configuration. Remember, I've never played with full blown race saws, and can't speak to that.

I knew I shoulda kept that damn saw....:biggrin:

I have an 038 Magnum under my bench with DDS written on over it my brother.

Sorta ya. Just don't go raising things too high. The transfer timing can have a fine line, its not hard to go too far.

you know you raised the ex too high when you reach the squish band.:hmm3grin2orange:

Well said. I've got a box of jugs that I went too far on. It ain't cheap to learn this stuff.

 

[Mastermind]

Very nice reading,thanks.I have a free straight gassed 026 on my bench which I will be porting in a month or so.I will just be widening the intake and exhaust ports,opening up the muffler and no base gasket.I do all my porting now with hand files and wet/dry sandpaper.The first saw I ported was an 026 heres a pic of the ports(don't laugh too hard).

No laughing here. That looks great. I can appreciate the work it takes to do all that by hand.

I add more and better tools every chance I get. I bought a Foredom knock off from Harbor Freight a few days ago. It's a 1/4 HP with a foot pedal. When I first spun it the thing sounded like crap. Like all their stuff it needed some love......I took it all apart, cleaned and lubed it. It works great now. For 60.00 shipped, it's way better than a flex shaft Dremel tool.

 

[MechanicMatt]

8-10 026's hmm???? Randy, you do some nice work. Looking at a engine as a air pump, its no wonder your saws run so well. You make that air travel very smooth my friend. Move more air in and more out. Younger guys at work look at me like Im nuts when I tell them a engine is just a pump, and needs air fuel spark. Your work is top notch, "MasterMind".

 

[stihl038x2]

On the carb question, has anyone tried boring one out ?

Steve

 

[parrisw]

No laughing here. That looks great. I can appreciate the work it takes to do all that by hand.

I add more and better tools every chance I get. I bought a Foredom knock off from Harbor Freight a few days ago. It's a 1/4 HP with a foot pedal. When I first spun it the thing sounded like crap. Like all their stuff it needed some love......I took it all apart, cleaned and lubed it. It works great now. For 60.00 shipped, it's way better than a flex shaft Dremel tool.

I love tools, that's a whole different disorder which I wont talk about now. I bought a used Foredom off ebay and am very happy with it. I wish I had the right angle tool for it.

 

[parrisw]

On the carb question, has anyone tried boring one out ?

Steve

Yes many do just that.

 

[stihl038x2]

Yes many do just that.

Do share !!

Steve

 

[w8ye]

The carbs on a 026 are 13.49mm. That's as big as a WT series carb comes. There's just nothing left to bore and still have a venturi?

You would need a HDA series? or a carb from a 044 or something?

 

[parrisw]

Do share !!

Steve

I'm talking in general, don't know how much room there is on the 026 carb, its likely you could take the venturi out a little. Some people just bore the venturi and some do the whole carb and make new butterfly's, I myself have not bored a carb yet, been wanting to.

 

[rms61moparman]

No laughing here. That looks great. I can appreciate the work it takes to do all that by hand.

I add more and better tools every chance I get. I bought a Foredom knock off from Harbor Freight a few days ago. It's a 1/4 HP with a foot pedal. When I first spun it the thing sounded like crap. Like all their stuff it needed some love......I took it all apart, cleaned and lubed it. It works great now. For 60.00 shipped, it's way better than a flex shaft Dremel tool.

That is exactly what I have.
I got mine several years ago when they were on sale for $35.00.
Still runs great.


Mike

 

[cowroy]

Randy, if you clean up the inside of the bore what do use to do so? The cylinder I am workin on doesn't have any transfer so no need for acid I just want to make it look like it has never had a piston in it without honing it. If it doesn't matter then I won't worry bout it. Thanks!

 

[parrisw]

Randy, if you clean up the inside of the bore what do use to do so? The cylinder I am workin on doesn't have any transfer so no need for acid I just want to make it look like it has never had a piston in it without honing it. If it doesn't matter then I won't worry bout it. Thanks!

If its clean then don't worry about it.