General view IT3 engine

Due to recent job change and house moving, I have not been able to put as many hours in the workshop as I would have liked. This will stay the same for a few months so I will concentrate on getting the main scheme of the car under way and start with the actual car design. This means the IT3 engine will be finished later but still on time to gather relevant info before the important design decisions on the V8 engine are made.

Some screenshots on the engine design almost finished. At this point it is missing spark plug and ignition hall effect sensor, and other sensors (Temp, Engine speed, Inlet pressure, EGT), carburettor, exhaust and engine stand.

The image below shows a cross section of the engine assembly. It clearly shows the main section of con rod, crank shaft and piston, on the lower part; and the exhaust valves and cam shaft on the upper part, behind the rocker carries section. Note the minimal cross section of the piston, quite innovative on an model engine of this size. The bore is Ø35 mm and stroke is 20 mm. Not quite to scale, but this allows for bigger engine capacity and thus more power, without significantly affecting overall engine envelope. Obviously the big flywheel will not be used on the V8 engine. On this test engine it will be used to, first provide enough inertia for the engine to not stall at low revs, and secondly to allow measuring the rough power of the engine.

Below is the entire engine, showing mainly the distribution system. On the V8, this will be different as only gears will be used. The depicted arrangement was chosen to test the gear system, but a chain is used to keep cost and complexity down.

I do not intend to bring into the CAD assembly all the fixings and other mechanical elements to reduce amount of time on design. Since this engine assembly is not too complex, it is worth taking the risk of not playing around with hundreds of fixings in CAD.

Overall very excited to start with the scheming of the car. I might start doing some 1:1 plots to start sketching by hand on it. Even perhaps a cardboard mock-up. This is always a good practice as it is the only way of getting a feeling on the size and helps a lot with packaging (engine, cooling system, control systems, batteries, etc).