I have a nexstar with a SuperTigre 40 and a straight Tuned Muffler. Every run I cover the side of the plane with oil, can I tip the muffler down to clear bottom of plane. Or is that not recommended?

You can tip it down.

You can also use an exhaust diverter on it. They are extensions that put the exhaust into the airstream a bit farther away from the airplane.

Sometimes where you point the exhaust works wonders. And sometimes just a bit further out is enough.

Thanks, didnt know if it would push up nose to fast or screw up air flow.

The diverters work great. I had a homebuilt where the plane was soaked w/oil... I installed a diverter, and I basically did not have to clean the plane after each flight anymore. A little Fantastic, adn in the back of the Suburban it went...

http://www3.towerhobbies.com/cgi-bin...&I=LXL378&P=ML

I use a deflector on my Alpha trainer, and it does a great job of keeping oil off the plane. On my Four Star, I have actually run a plastic tube from the muffler and tie-wrapped it to the landing gear. I took out the muffler baffle to compensate for the added resistance, and it works and sounds great (OS 46LA).

I am putting a Super Tigre 45 on my current build. Those mufflers are pretty bulky. I would expect to get some resistance from it if it is tipped too far. I am planning on a deflector for that as well.

I am getting one for my trainer, it gets soaked in oil.

A tip for you folks using (or planning to use ) exhaust diverters.

The diverters have a NASTY habit of coming off (usually in flight ) and being lost.

Take a Dremel OR a small triangle shaped file and cut 2 shallow grooves all the way around the exhaust nipple on the muffler.
When you put the diverter on the muffler, use a small hose clamp to secure it in place instead of the plastic zip-tie.
The hose clamp wil force part of the diverter into the grooves and prevent it from falling off.

Good idea Campy.

I agree with Rock. I have used diverters for exactly what you want to correct. They are inexpensive, very light and don't add weight and can be set up without altering your existing muffler.