Time to plan and scheme for the next project!
The previous 1098 engine & gearbox project is now running and driving really nicely. It took me about 5 years from start to finish as I took my time collecting parts and getting all the work done.
viewtopic.php?f=5&t=85524So, this time is something completely different... The normal Aussie 1098 engine is a long stroke (83.8mm) and small bore (64.6mm) engine, and shares the engine block with the 998. The long stroke engines traditionally have better bottom end power and less top end power, and small bore engines can limit the size of the valves that you can fit. They also have a higher piston speed due to the distance they have to move each revolution
What I've planned for the next engine is a short stroke (68.4mm) and big bore (70.6mm) engine. This configuration was used on the 1071 Cooper S to compete in the 1100cc class. Later on in South Africa they made short stroke crankshafts so that they could make both 1100cc and 1275cc engines from the same engine block. I'd heard of a few guys in the UK turning these into fun little engines, and it sounded like something I'd like..
So the starting point:
1100S Auto block - standard bore
12G940 head - standard 9 stud
12G2827 crankshaft - standard/standard grind (2.0" main and 1.75" big end)
1100S standard rods and pistons
So this engine will be built up as a high rpm revving engine. I think the block has all the modifications done to convert to a manual gearbox, the head will need a service at a minimum and I'll consider getting some bigger valves installed. The crank will need to get ground to at least 010 undersize but they are considered one of the strongest cranks available due to the large journals and overlap between the main and big end bearings. The rods have the heavy caps on them, so will need to be lightened at a minimum before I use them.
I've still got lots of decisions to make regarding the final spec, and this will take another few years to get the parts for and the machining work done. I'll have to add in a disc brake kit before I get this done too
Attachment:
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And why not just do a 1275 engine? I guess just because I can and want to do something different