1981 bmw 320i

My car starts get 62psi out of fuel pump but will not rev past 4000rpm anyone know what might be wrong

Just about anything, except the fuel pump. Ignition, fuel injection, engine compression, you name it. You’ll need to be way more complete in describing the history and problems this car is having.

I agree with Texases. Two possibilities that jump to mind are a clogged exhaust and ignition timing that’s no longer advancing with RPM. But there are a myriad of other possibilities.

There are a number of things that it could be but if the assumption is made that the problem is not related to a clogged catalytic converter then it’s more than likely going to be in the fuel injection system.

This car should have CIS on it (and if the converter is not clogged) you need to check for vacuum leaks first off. The best way of doing this is with a vacuum gauge. CIS is extremely temperamental to any vacuum leaks at all.

You checked the fuel pressure which is at 62 PSI. Do you have the special fuel pressure test gauge for CIS? A normal fuel pressure tester will not tell you the whole story about CIS pressures.

Any check engine light?

4000 RPM in any gear? If it won’t exceed 4000 in low gear (low load) then you can rule out fuel delivery or weak spark and focus on Mountainbike’s suggestions.