Heads Under Pressure Snowmobile Head Design Team Members: Peter Britanyak, Nick Harker, and Chris Tockey

Deliverables Head re-designed to accept pressure sensors for in-cylinder pressure data Research on whether casting the head is feasible and cost effective

Specifications Pressure sensor to acquire in cylinder pressure data Starting with the design used on the Evinrude outboard motor Not responsible for data acquisition Sparkplug Shorter electrode (NGK) 30º sparkplug angle from deck surface Maintain current location Injectors Design injector seating as per drawings 9º injector spray angle towards intake side Near nozzle geometry as per drawings

Combustion Chamber No dome offset Squish area same as turbo head 34% Dome height approx. 1 inch as necessary for compression ratio Dome angle needs to be determined for the correct compression ratio Compression ratio of 6.5:1 Dome radius.75 inches Cone to plug distance is -.08 inches Squish velocity of m/s Squish diameter of 1.95 inches Squish radius from cone to squish.25 inches (double turbo head)

Manufacturing –Research casting as a method to manufacture the head Report on viability and cost Obtain Head bolts long enough to prevent stripping and uphold aesthetics of motor

Pressure Sensors  Contacted Kistler about part # 6052C Cost: $2500 each Cost: $2500 each  Not part of our budget (from Karen)  There are detailed drawings available so the head can be designed without buying the sensor.

Sparkplugs From past experience NGK sparkplugs have been the most successful. The aim was to use a plug with a shorter electrode to prevent it heating up and causing detonation at high revs. As of now we are still working on the decision of which sparkplug to use. The challenge is finding the sparkplug that will allow for a plug to injector spray cone of -.08 in.

Squish Velocities

Squish Velocity Value Range

Configuration 1

Configuration 2

Configuration 3

Volume Comparison For Config. 3

Plug to cone issue Original Specs: –9º injector angle –14º cone angle –-0.08 in cone to plug distance Modified specs: –7-9º injector angle –22º cone angle –Electrode touching fuel cone

Injector Seating

Casting Contacted Eck Industries and D8 Toured D8 facilities talked with owner about the possibility of casting: $3-4k for pattern with approximately 4 week lead time $ per casting with approximately 1 week lead time Contacted Travis Pattern and Foundry in Spokane. Minimum run of 50 or more. Referred By Travis Foundry to Lost and Foundry Sells casting equipment Ability for in house casting Setup Cost $400

Casting Pros and Cons Pros: After initial investment, cheap and quick to make. Easy “quick” prototyping Casting knowledge and experience gained to team Easier to implement design changes with cast head blank Cons: Expensive initial cost Out of house (less control) Time to create first head Unknown design criteria Still requires machining of final surfaces

Decision points Pressure Sensor (6052C or other?) Spark Plug type Squish Velocity (Specific RPM or band?) Combustion Chamber design Plug to cone distance Manufacturing (Casting)

Current Budget Plugs –$12 each Manufacturing –Casting D8 - $4000 initial + $200 per cast Lost & Foundry (in house) - $400 –Machining Material – Billet Aluminum $100? Tooling – In house $100? Bolts –ARP approximately $100 Gaskets –Not yet researched - $100?

Future Plans July 10th Design Review July 12th Sparkplugs ordered, pressure sensors chosen. Decide on manufacturing process. June 17th First Iteration sent to Andy and Justin for review June 24th Completed iteration sent to Andy and Justin for review Aug 4th Design Finalized and ready for manufacture.