Does anyone have any pictures of their engine installation and how the cowl was cut to accommodate head and muffler. I am currently trying to finish up my plane with a Saito 100 engine mounted horizontally. The Saito came with the "new and improved" muffler and I will have to pretty well butcher the cowl to make it fit. The Saito straight pipe coupling is perpendicular to the engine. The pipe and muffler will require a huge hole so the cowl can be installed. The muffler can't be screwed on after the cowl is installed. Hindsight is 20/20 but I probably should have invested ($90.00 USD) in a Pitts muffler for the Saito. Alternatively, I could have tried an inverted installation (didn't want potential problems with my first 4-stroke engine).

I think I will probably see what I can do with the standard muffler for now and order a new cowl for the next attempt. Just want to get it in the air for now. Pictures, ideas and suggestions are welcome!

Ross

After butchering a cowl to try and get the saito to fit horizontally, I gave up. I ordered a new cowl, changed the engine to inverted and then cut the cowl for that.

Part of the issue that I had with the side mount was having enough room to get the cowl on and off. Even with a huge hole, it was still difficult to get it on and off. With the invert mount, getting the cowl on and off is easier.

EXACTLY!!!

I have also ordered a new cowl and will try again with the inverted installation. In the meantime, I may just continue with the hack job so I will have something to fly and fix it properly later.

Do you have any pictures of your inverted installation? (I assume you used the standard POS Saito "improved" muffler?)

Ross

Here is a picture of mine with a Mag .91 4s mounted horizontaly in it.. Fit right in there... But then Magnum doesn't have that straight pipe exaust manifold Saito does...

I had it very nicely cut out to accommodate the engine head. Perfectly centered and a small hole perfectly aligned for the needle on top. I thought I would be able to let the straight pipe out through a fairly small hole in the cowl and attach the muffler afterward. When screwed all the way in, the muffler is about in the middle of the cowl. Even if I made the hole large enough for the muffler, it won't work because the muffler cannot be screwed on with the engine mounted (hits the firewall). Have to attach the muffler, mount the engine and then install the cowl - needs a great huge hole in order to slide the cowl over the muffler. I might slit the cowl and open it up to go over the muffler and cover the slit with some vinyl trim.

As I said, the only way I can see that it would work is to use a different exhaust or mount the engine inverted. New cowl is ordered.

Ross

Know what you mean.. I have two Saito .56's and two .72's... One of each has the new (straight pipe) and one of each has the curved pipe... I lost one curved setup in the air and found out I can order either style these two engines from Horizon.. Not sure about the 100 though.

Yes this problem does bring back memories...AAARGH!!!

I put an OS 1.20 in mine and after seriously butchering my cowk=l I ended up ordering a new cowl and a slimline muffler to avoid the butchery. I still had to slit the cowling on the bottom to allow me to spread the cowl a little for installation and removal, but it looks ok and flies great!!

Do fly nice don't they...

I ended up with a large hole in the cowl on mine, too, but it's my first cowled engine. I was able to put the muffler on after the cowl, however. First I screwed the straight header pipe as far into the muffler as it would go, but still loose enough to turn with my fingers. I turned the lock nuts down to the muffler, too. Then, I placed the header in position to thread into the engine. I turned the header pipe with my fingers so that it unscrewed from the muffler as it screwed into the engine. When it was all the way into the engine, I tightened the lock nuts on both ends. A final tighten on the nuts while the engine was hot, and it hasn't given me any problems yet. There seems to be plenty of thread in both the engine and muffler. It is critical to get the threads positioned right at the engine so that they engage right away, though, so you don't end up with too little in the muffler. It helps to have small fingers!

Steve

Steve

I was thinking about trying that but I was concerned that without full thread engagement, I would run the risk of the threads wearing excessively due to engine vibration. I realize that if everything is tight enough for zero movement, it shouldn't be an issue but if it loosened up a bit it could damage the head. I may give it a try before I completely hack the cowl. Do you have any pictures of your installation?

thanks for the suggestion.

Ross