Closed Chamber refers to the shape of the combustion chamber. If I recall correctly it's refering to a chamber that has a large quench area... when the piston compresses the gasses in the the chamber as the piston hits TDC there is a "quench" area that forces the gasses into a MUCH smaller space this ups the "compression ratio" of the engine but kills the flow of the heads as the valves don't have the same clearance on the sides.

a "small journal" is refering to a rod or crank journal. A Journal is the part of the rotating assembly of the engine that the bearing travels around. Journals are found on the Crankshaft, Camshafts, and connecting rods. The size of the journal determines if a part will fit in that engine or not.

Close ratio transmission refers to the gear ratio's in a transmission. Close ratio means that the difference in the gear ratio's is smaller or close together... for example the following are 2 sets of gear ratio's for GM transmissions... you can see that the ratio's for the first one are much closer together than the second

2.52 1.52 1.00
3.06 1.62 1.00

All of this information is readily available for all who want to know by simply looking use the ctrl+n function of your web browser to google something you're not familiar with. It's the best way to learn.

All of the information that I provided is EXTREMELY simplified. There is a great deal more to understand everything.