No.
I'm doing something else right now for a GTP article, so I just happen to be testing car speeds at SSRX. I'm measuring two of the four straight sectors and the top speed. I was testing the Mustang Gr.4, on circuit BOP (not oval BOP), so when I was done I hopped out, painted it P8 Matte and went back to do the same test.
Mustang Gr.4, standard paint:
Top Speed - 171mph
S1 - 1'06.926
S2 - 1'05.925
S4 - 1'06.220
S5 - 1'06.218
Mustang Gr.4, P8 Matte
Top Speed - 171mph
S1 - 1'06.928
S2 - 1'05.924
S4 - 1'06.220
S5 - 1'06.219
That's 0mph faster and 0.002s slower over 20km (each straight sector is 10km) for the P8 Matte car, equating to a 0.001mph difference at over 168mph, and thus of no statistical significance.
Or "tripe".