Briggs & Stratton 206 Rules Update – RLV Exhaust 5506 and Rocker Arm
Briggs & Stratton 206 Exhaust -5506
This week RLV will begin shipping 206 exhaust systems which will now feature a main brace back to the control cover along with an additional non-welded brace that extends from the cylinder head. The exhaust dimensions and pipe angle remain unchanged along with the current part number 5506 will remain the same.
“One of the main failure modes we looked to address with the support of RLV happened during the installation of the exhaust system itself” stated David Klaus, Director-Briggs & Stratton Racing. “When a ridged system isn’t properly aligned during the installation the unintended force created increased the chance of failure. This new system will allow the pipe and braces to be installed separately naturally correcting this situation. Allowing the exhaust to ‘float’ and bracing from the top and bottom of the exhaust further helps to dampen the harmful harmonics that can lead to failure.”
Some additional advice to extend the life of your 206 engine and RLV exhaust system:
- When installing header wrap do not overlap the wrap by more than 1/8 inch. Excessive overlap traps heat in the pipe and in the cylinder head.
- Start 2 to 3 inches from the flange when installing header wrap to help exhaust heat to escape. Excessive heat can cause head or exhaust valve warping.
- Engine mounts – Just because a mount allows for additional engine offset does NOT mean you should do it! Excessive offset and the use of a thin aluminum base plate (typically machined to save a few grams further reducing strength) amplify vibration throughout the engine and system. It will also impact fuel metering as vibration agitates fuel (hint, hint).
- Install the engine with no more than a ¾ inch offset. When a ‘typical’ ½ inch plate is used and offset beyond this, strain gauge tests shows up to a 20% increase in vibration measured at the valve cover. This is a TREMDOUS amount of additional vibration and does not take into account any common contributing sources of vibration (track surface, tire balance, bent axles, etc.). Vibration accelerates fatigue.
- Use a QUALITY mount. The BEST on the market is the Odenthal mount. It allows for greater offset without sacrificing rigidity. Another system would be the PMI engine mount with the ¾” engine plate verses the standard ½” plate.
- If your track is not a part of the Briggs & Stratton Weekly Racing Series you are missing out on over $50,000 worth of track and racers prizes. “This bullet point improves the lives of our 206 racers through fun, some bragging rights, and great prizes.” BriggsWRS.com.
Briggs & Stratton 206 rule update -3/25/15
Rocker Arm Minimum Length on P/N 557015
Machining advancements in our final trim die is resulting in the small tab highlighted in the image below being reduced. This does not impact performance or require any attention by our racers. The new minimum simply reflects the reduction of the tab as shown.
24F: Rocker Arm – overall length 2.825 inches minimum. Can be checked using a dial caliper.