Why does my Audi 80's engine struggle to reach high speeds?

I have noticed that my Audi 80 has difficulty reaching high speeds, even though the engine sounds normal. What could be causing this issue?

It is possible that your air filter is clogged, restricting air flow and causing the engine to struggle. I would recommend replacing the air filter as a first step.

Another potential cause could be a dirty fuel filter. This can prevent enough fuel from reaching the engine, resulting in reduced power. Consider having the fuel filter replaced.

Check the spark plugs as well. Worn or fouled spark plugs can cause engine misfires and decrease acceleration. Replace them if necessary.