does anyone now how many psi in a stock 87 t2 fuel pump,am doing a swap in to 84 gslse

 

There is no pressure in a fuel pump.

Do you mean how much pressure can the pump make? Depends what the flow is. There is no single answer to your question.

I wouldn't put a TII pump into a GSL-SE unless you have some form of fuel control. It will make the mixtures richer, meaning increased fuel consumption and less power. Get the right pump for the car.

I though the GSL-SE used an external pump? If that is the case, you can't use an FC pump anyway...