Hi, I changed the 165/70-13 of my r9 to a 185/65-14 of a r21, I don't know what's the better preassure to these tyres, if the preassure of r9 tyres or the preassure of a r21 tyres.

My car is a r9-tse of '84.

Mike.

Hi Mike
I think you should go to your tyre manufacturer or reseller and ask them about the tyre pressure, cause pressure is a weight:area ratio, and in your case weight hasn't changed alot by the 14"wheels, but area might have changed due to the tyre width, so I don't think you can still apply the same R9 13" pressure now.
Ask the tyre shop you bought them from and keep the vehicle's weight in your head they might ask for it.
And that's only my humble opinion.