whoops that extra nought has caught me out!!! I’m in Normandy, just outside Honfleur. Very pretty, eating garlic sirloin steak off the bbq at the moment and a plate full of French cheeses. Oh and a bottle (or 2) of Bordeaux followed by the local Calvados. When in Rome.......
The other reason the rev counter might have said 10000 is your rev gauge is double reading. Half those numbers make sense for a performance VW engine. A stock VW T1 engine is specified to run up to 4000 RPM or 69mph with stock everything. People find that going to 5500 RPM is OK and nothing falls apart but it wears things out fast. The redesigned T4 is specified to 4800 RPM.. According to my Keith Seume book of silly engines, (The VW Engine Interchange Manual) by balancing things, changing connecting rods and their bolts you can make a T1 engine go to about 9000 RPM.. But it really only does it for 10 seconds and a 1/4 mile before heat has any effect.. leaving off the fan belt for more power and RPM is a done thing.