Getting there,,,

Another couple of hours were spent at the workshop today to make the measurements required to the cylinder head to allow us to calculate the compression ratio. First of all Wayne machined a new angle into the exhaust ports, making a step from ~30° to the standard ~45° as opposed to the exhaust gases charging right into a 45° angle. This will just help everything flow and hopefully make the turbo more efficient. After this the outer edge of the combustion chamber is given a bit of vaseline and a squared piece of perspex with a tiny hole is placed on top. The vaseline is used to provide a seal so a liquid can be poured in with use of a burette, and thus we can measure the capacity of the chamber. The chambers turned out to hold 53cc and this figure was than used to calculate alng with the swept volume, the compression ratio with a flat piston. The end result was 7.68:1 which is pretty much ideal for our application.

Anyway, here is a photo taken today of Wayne making a mess, and making noise while blending in the valve and combustion chamber.



Next on the to do list is to find a suitable cam for the engine...

A brief, green and shiny update

Good evening all.

Today Me and my Brother spent a couple of hours dummy building the bottom end. A matter of putting the main bearings in with the crank and attaching a piston and rod to it so we can make accurate measurements to work out compression. Everything went together nicely and with a little oil everything moved smoothly. Next up we need to get the head to the workshop and measure that too. The pistons are +1.5mm so the overall capactiy will be 1659 - the additional torque over standard 1597 will be very welcome.