We use tongue mufflers that free flow. Uniflo tanks, exhaust pressure to uniflo vent. If we encounter weirdness we cap uniflo vent and run pressure to overflow. Tower head gaskets are 10 thousand, OS FP gaskets are 15 thousand. Jim Lee sells head gaskets for this engine of different thicknesses. I have run a lot of these. Some all out on sport planes, some as stunt engines on sport planes, some as stunt engines on light profiles for stunt, some on thick winged planes between 500 and 540 or so cubes. Sometimes the Towers run perfectly with little or no break in. I've a Tower on an Oriental ARF still breaking in after 20 flights. After 20 flights I am still getting black exhaust. A friend having lots of experience with bushed engines in slow combat said it was the crank/bushing fit wearing in. The chrome brass line/piston fit, usually doesn't take much break in, it's the crank. News to me. But he appears to be right in this case. Engine is running in, exhausting less black, gaining power and smoothing out.
These engines need to be tuned in to your plane. Weight, airfoil drag, wing area.
Examples:
1. Cheater Magician. Tail moments extended, stab and elevator increased by 30%, flaps widened. Outboard flap 1/4 inch wider at tip than inboard flap. Fabulous flyer. I used a light stiff half inch piece for the fuse and a Walter Umland wing kit. Plane weighed 33 ounces all up, motor and tank. Tower was set up with 25 thousand head gaskets, .265 venturi and OS clicker FP needle valve. Dead smooth repeatable run. Wet 2, leaner 2 break. Loved that plane.
2. Prowler. Flea market special. $10. Excellent flier until a flap hinge pulled out on inverted laps. Wam. Plane weighed in at 46ounces. All head gaskets were pulled out in order to get an effective break. Head on cylinder, no gasket, worked on this engine. Lucky. .283 venturi, OS fp clicker needle valve. The Prowler considerably more drag than the Magician. Thicker airfoil. Much heavier. Palko and Banjock kept after me to pull out head gaskets and open venturi. I thought bull. It worked. Setup this way the Prowler had good power and a useful break. Otherwise not enough power. I had the Magician engine available. (The Magician had gone in on the L-Pad when the bellcrank pulled out, victimized by a...) I didn't believe my friend, bolted the Magician engine on the Prowler. It behaved identically. I wound up pulling out all head gasket and using a large OS Venturi with an FP needle.
3. Galaxy. Ten year veteran. Weight unknown. Tower 40, .272 Venturi, FP clicker needle valve, 30 thousand head gasket. Runs very sweet. Perfect for practicing pattern on 60 ft lines.
4. Oriental ARF, recovered, reinforced wing, 3 ounces of tail weight, all up weight 46 ounces. Engine breaking in. Set up like Prowler.
Plus others including Vectors, a Buster run all out, and and.
I use Power Master 5% and 10% nitro, 22% oil, fifty/fifty castor/synthetic. 10% nitro is my preference these days in all conditions. Fatter needle. Wider range of needle valve setting. Plugs Enya#3 or Thunderbolt RC. 10.5x4.5 APC sport prop. I'll probably do some prop experiments with the Oriental. Power still not optimum. Engine breaking in. See above.
Topic: Tower 40 (Read 2206 times)