Aliased cubemap reflections :(

Hi community,
I’m working on car paint shader but I have a problem with the quality of the reflected cubemap. Actually my environment is a high quality HDR map (8000x4000) displayed at 1024*512 in game. (2048x1024 makes no differences)
I’m trying to have a very sharp/high quality reflection, but as you can see on the images, the reflections look nice when I’m close to the hood but they are getting very very dirty/aliased as the camera goes away from the car hood…and I need to solve this problem.
I tried every kinds of “Mip Gen Settings” for the HDRI map but nothing works… Any idea ?
Thank you !

the hood with carpaint:

the hood with a chrome shader close and far from camera:

up :rolleyes: