OK I answered the question of what engine is better. 2bbl or 1bb. (in my mind anyway) The 2bbl is a far better engine. I just ran one tonight I built for a guy that needed one ASAP. It turned an APC 16x8 prop at 8320 rpm. That is amazing for a new engine. The 1bbl models are doing around 7800+ when new. The 2bbl models seem to be consistantly higher. Usually over 8000. Keeping in mind they will pick up 600+ rpm as they break in. I think the reason is the transfer ports. I mill them deeper on the 2bbl engine. The 1bbl has a huge intake port but very small transfer ports. A poulan 25cc has larger ones. That is the only reason I can come up with for the increased power. I open up the intake, exahust, and transfer ports on the 2bbl. Just the exahust on the 1bbl. No real way to safley open the transfer ports on the 1bbl. I still didn't get the bad engine back so I am taking a chance with the milling. The worst that will happen is I will have to build another one.
So to sum up, the 2bbl, even with the smaller intake, even after milling it open, still has more power than the 1bbl. That is what i am finding and I have converted 27 of them so far. About half 2bbl and half 1bbl.

Hi Scott,
The smaller 2bbl intake must compensate through higher volocity. That small transfers were the first thing that I noticed when I diassembled my first 1bbl. After converting so many engines with great success, that one engine problem may be something unrelated to your mods. Thanks for sharing your experience.

Dave

Hello Dave, Forgive for jumping in here, I have a Mac' 22 (10-12 years old)and have it installed in an NOS RC boat.(Found in freinds attic!) How do I break-in this type of engine? I have Nitro engines that have lasted for years with proper break-in, do these act the same? Can I make a type of custom exhaust to vent the exhaust out of the boat hull?(instead of pointing down inside hull) Also I have read that I should use "Camp Fuel" ie. White Gas mixed with Amsoil, 4-6oz./1 Gal of fuel. Any help would be appreciated

Hi Ritz,
You would get more responses with a new thread,but here goes. If the engine isn't broken, you can run it on 32 to 1 mix (4oz. per gal) for the first couple gallons then switch to 40 to 1 mix. If it has a water jacket break it in in the water, moving. You can find mufflers and other parts at Wackerengines.com. Pete does have boat mufflers. Anyway, don't let it over heat. Good luck.

Dave

Where has everyone been? I soo look forward to getting an email that someone responded to this post Just wondering if any of you have actually flown a Toro. They do very well in the air. I have one on a 14lb Sig Rascal 110". It flies like a dream. My buddy has one on a 1/4 scale Space Walker. It is amazing on that plane. Many of the engines I have sold are now flying with happy pilots. Just wondering about all of you.

Hi Scott,
I am still here. Rollmyown is alive and well in PA. That is good to here that you have had such sucess. I havn't flown one yet. Working getting a big mule airborn. Flying season is year round here in south Texas since we are on the same latatude as south Florida. I bought a poulan 46cc off RCU and it has a bore and stroke of 40x31.5mm. This works out to 40cc for me. What is the bore of one of your 46cc Poulans? This one came from a Craftsman saw which was labled 46cc. It has the coil mounted on the cylinder like the 46cc, but has a flat on top with no vertical fins like 46cc I have seen. Nice motor with a chrome bore and CH adapter. I havn't been able to track it down by part number. I am glad that your E-mail notification works, as mine don't. I seen you mention the Sig Rascal a couple times and thought that the 110" was a typo, but I gusee it is correct. This must be a big floater at 110inches. Stay warm.

Dave

Hi Scott,
I have some airplanes but they are not suitable for a Toro, so I haven't flown one. They are also not powerful enough to get my 4 ft tree stump off the ground. The building season is here in PA now, but I keep getting sidetracked with other stuff. Too much tinkering with engines also. I am planning on an airplane that I can try more than one engine on. The other thing is that airplanes are getting bigger and I am running out of room. This has to a common thing with us modelers. Time is going by too fast also. I also wonder when you get time to fly with all the engines you build up.
John

Dave, I did some checking and your engine is indeed a 40cc. It is the same basic engine as a 42cc like in a Wild Thing saw but for some reason just the 40cc has the coil mounted to the engine. That is nice to know. I was looking for a 38cc class engine to convert. I think you helped me find one Thank You!

Time to fly has been limited latley. I have been selling a ton of engines in the past few weeks. Everyone is buing stuff for thier winter projects. It should slow down soon. I have a few planes to get done too. Too many projects and too little time.

OK, My last Toro, with some new mods, 2bbl model, spun an APC 16x8 at 8500. That is just amazing for these little trimmer engines. Look out Zenoah G26, 8900 is getting closer

Someone has new Toro engines on Ebay. Says he has a pallet of them.

Yes he still has some but they are comming to an end.

Hey Guys. I have some video I wanted to share. I test ran toro yesterday with smoke. Man did it smoke !

[link=http://www.scottellingson.com/brillelle_25cc_gt_smoke.mpg]scottellingson.com[/link]


[img][/img]

Hi Scott,
Man, that really smokes great. Did you just install a standard nipple or does it have a coil inside the muffler?

Dave

Just a standard nipple pushing the kerosene across the exahust port. It worked very well. I did it to a Poulan 46cc also and had the nipple about 2" from the exahust port. It didn't smoke near as well.

Seen the video. Dude that is wicked on an engine this size.

The best part is, that was with kerosene. That isn't the best to use. It has no hang time. I want to try some real smoke oil. My neighbors allready think I am nuts running these engines all the time. Wait until they see the smoke fog roll by

Hi Scott,
I agree also, that is a smoking fool for a 25cc engine. I saw a smoke test on the ground of a full scale biplane once and your test reminded me of that one. Your smoke really looks dense, the neighbors are going to love it! I must be doing something wrong because I have never started a Toro with one flip like you. Most of the time, almost all of the time, I need an electric starter. My computer stopped receiving emails, That needs fixed along with a few other projects. I am also building a new PC, so I should be able to really see the video. It is pretty cold here now to be testing engines. How cold was it that day when you one flip started that engine?

The Toro's I have done seem to flip start fairley well. I tried a different carb on that one and it was the ticket. It is a WT 15. It is 11.11mm and needed to be modified a little to work. The fuel came in on the tip cover. It had no other fuel imput. I had to drill a fuel input in the regular place and use the top cover fitting for th pulse. It Worked well. I had to buy a couple carbs from MD mower for $40 each. Ouch! I was out of carbs. The thing is the jetting must be just right for the Toro because it ran smooth as silk no matter were the throttle was. Usually they get a little rough in the mid range but this one was perfect. That engine also hand started very well. Better than any other. It was a little warm in it video. I had run it about 10 minutes earlier, but not for very long. It they are cold cold, then an electric starter is better. They still hand start but not near as easy. But if it were on a plane and you landed to refuel it would easily hand start again. Carbs are the biggest thing. I always use new ones but some work better than others.

I just ordered some avaition smoke oil to try. It should be better yet. The kerosene smoked well, but disipated fast. The smoke oil should have a better hang time. It was about 40deg the day I did the video.

Hello Scott, The last day I ran some engines it was around 60 degrees so it wasn't the temperature, I don't think, was giving me problems. I suspected that the carbs I was using are the problem so that is what I will concentrate on getting right. From what you are saying about carbs, that has to be my problem. I will get it all straightened out one of these days. When you get the right carb on a single cylinder engine and put some time on it, the old inspect the plug for proper combustion idea, will probably work with these engines as well as any other. Time now to catch up on building.

A friend and I are messing around with the toro two barrel motor..I have read through the thread here, and I know I saw something about mufflers.. Does anyone reccomend any mufflers in particular? as far as performance, or maybe a cheap good value one? Just wondered what the bolt up alternatives are to modifying the stock type...
thanks... lots of good ideas in this thread

Hi, The stock muffler will actually work pretty well. Very quiet and not a ton of restriction. I make mufflers for the ones I convert. They are louder but lighter and less restriction. It all depends on what you want. You should pick up a few hundered RPM with a good muffler but if you want quiet, the stock one is fine. I will actually test one in the next couple days and see the actual RPM difference. I have one here I test ran yesterday. It spun an APC 16x8 at 8550. I will see how much it drops with the stock muffler.

Poco242, How broke in is the motor that turned 8550 RPM.

It is absolutly brand new. It was the first run on the engine. I did it in my shed using regulag gasoline and a 50:1 oil mix. I use a laser tach to check the RPM

I was just wondering because you said the one you are sending me only turns 8150 RPM.