More dyno #'s Ported vs oem 100 vs 92 and ignition advance

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Diesel torque. Obviously oil is fuel. Why do those things run forever on oil fuel instead of solvent fuel. Is oil a cushion for the pushin. Hmmm. I think so.

Obviously oil has more carbon or you wouldn't limit it's mix ever. Carbon versus Cushion.

I really enjoyed that piece on drone/rc plane engines, but i don't have the link.
 

It is a mixture of slightly heavy iso-alkanes, methylcyclopentadienyl manganese tricarbonyl (like a lead substitute, this is a big molecule), and napthenic compounds. I too bet it works as advertised.

Randy, you should try a couple boosters I could recommend. I need to track them down first. They have a high percentage of nitrated compounds, but still mixes in gas.

About the more oil stuff. You guys do know the oil burns too yes? It doesn't just go out the muff into thin air. And lastly, when a saw is burbling at full throttle and only cleans up under load, that motor is running pig rich. It isn't as easy to change jets as in a snogo, which I do when there are wide swings of temperature. Wide meaning +/- 10*F. And no I do not follow the thermometer. But if there are going to be a few days when temps are down or up, yes I will spend 15 minutes to changes the main jets in my snogo. It is 570cc of air-cooled fun, so it relates.

Try tuning your saw to just barely four-stroke then go do some cuts. The best way to test this will be to have a nice long thick log so you can have the saw under load for a minute or so, then just shut it off. Look at the plug and the wash. This will tell you more than anything else (unless you have EGT), how your saw is tuned.
 
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Diesel torque. Obviously oil is fuel. Why do those things run forever on oil fuel instead of solvent fuel. Is oil a cushion for the pushin. Hmmm. I think so.

Obviously oil has more carbon or you wouldn't limit it's mix ever. Carbon versus Cushion.

I really enjoyed that piece on drone/rc plane engines, but i don't have the link.

Diesel also has more BTU than Gasoline. About 13-15,000 BTU more per gallon.
 
The higher the compression the more heat they make. Feel it with your hand above the chain cover when you rev up the saw.
 
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So what if you had a saw with stupid hi compression (275) run it on heavier gasoline, or blend there of, would it make more power? or just burn up?

Thinking out loud here .......

At about 240 psi on the blend of juice I run, the saw I was testing on started running lean and acting funny at wide open throttle. I think it was pre-igniting the mix and running out of fuel before the combustion process was complete. Remember.....I said, I think. :D
 
So what if you had a saw with stupid hi compression (275) run it on heavier gasoline, or blend there of, would it make more power? or just burn up?

Thinking out loud here .......

More likely it would just ventilate(blow up)before it burnt up.Engines that run higher energy fuels(like diesel)are of much more robust construction than a two stroke saw engine.
 
At about 240 psi on the blend of juice I run, the saw I was testing on started running lean and acting funny at wide open throttle. I think it was pre-igniting the mix and running out of fuel before the combustion process was complete. Remember.....I said, I think. :D

My 444SE started to detonate at 245psi cold(never measured it broken in...it was detonating, afterall). It would start, do one cut fine, then detonate on the third or fourth cut. WOT for a fraction for a second, then it would die or just totally lose power. I showed the piston to Nathan, and it looked like detonation.

That was 40:1 94 octane non-ethanol, btw.
 
If the motor gets too hot, you'll begin to see aluminum transfer on the top of the piston and combustion chamber. It looks like tiny bright specks of aluminum. These are the remains of molten aluminum droplets forming and fusing to whatever they hit.
 
At about 240 psi on the blend of juice I run, the saw I was testing on started running lean and acting funny at wide open throttle. I think it was pre-igniting the mix and running out of fuel before the combustion process was complete. Remember.....I said, I think. :D

Do you still have that saw? I bet higher octane would have made that thing rip.
 
Do you still have that saw? I bet higher octane would have made that thing rip.

According to Torco's info I should have been at 102.....

I dropped the compression back down. After 200 - 210 they just make too much heat. I had to know how much was too much though.
 
How do you drop the compression once you're up that high?

Several ways. You can raise the exhaust a couple of degrees, take a bit more out of the squish band, or add a thin gasket under the base. On this one, I cut .010 more from the squish and raised the exhaust two degrees.
 
I changed that a bit for the 372...

91 non-E
4 oz WD40
3 oz per gallon Tobasco sauce.
28 grains IMR 4350 smokeless powder

Made it run mean as a junkyard dog...

For a GTG, substitute your 4350 for 15grs of Bullseye.
 
According to Torco's info I should have been at 102.....

I dropped the compression back down. After 200 - 210 they just make too much heat. I had to know how much was too much though.


Just askin cause I don't know the answer. Would running av gas have helped the heat problem. A friend of mine is a helo tech and told me to run it in my RM 250 when I brought the compression too high and it was getting too hot. I ended lowering it down again after a few weeks because I couldn't always get the av gas, but it ''seamed'' to help, but then again, I ran a bit heavier mix because I knew the higher octane would allow it.

Another please.
I just opened up a friends redmax g561avg, and it has true signes of detonation, so I'm trying to figure out the cause. There was a fair amount of carbon buildup on the exhaust side of the piston, and both the squish band and piston have divots. The piston has lost about 1mm on the exhaust side, but the rings and skirts look really good with very little wear. Carb set too rich or mixed too rich is what I was thinking. I was leaning more towards mixed too rich or the wrong oil used because it can cause carbon build up, increasing compression, causing detonation.... These saws already have high compression because they have a longer stroke than many saws and have a domed piston. Am I on the right track. I'm doing this one as a favor for a friend in a bad financial situation, so he asked me to just get it to work better for as cheap as possible and asked me to tear it apart and redneck it to last another year. He passed me the saw and said ''It has a loose muffler, broken pull cord, broken brake with missing parts, revs slow and not running like it used to. Can you fix it for me buddy'' I'm a sucker for a friend in need.....even when he doesn't take care of his stuff.
 
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