The generator matrix

 1  0  0  0  0  1  1  1  1  1  1  6  1  0  1  2  1  4  1  2  4  4  1  1  6  1  1  1  1  2  6  0  1  1  0  4  2  0  1  6  0  1  1  4  2  0  1  2  1  4  1  1  1  1  0  1  1  1  1  4  2  1  1  6  0  1  6  0  1  1  4  1  1  0  1  1  6  4  1  1
 0  1  0  0  0  0  1  3  3  7  7  4  4  6  1  1  6  1  5  1  1  1  2  6  1  7  6  4  4  0  1  6  6  0  1  0  1  4  0  1  6  1  2  1  6  1  7  2  1  1  0  3  6  1  4  4  3  2  1  1  1  2  6  2  1  5  1  0  7  3  6  1  4  2  1  6  1  4  3  0
 0  0  1  0  0  0  4  0  4  1  3  1  5  1  2  1  3  3  5  2  6  1  1  6  4  1  7  0  5  1  5  0  2  2  4  1  2  4  6  3  1  5  3  7  1  2  2  6  7  3  2  7  4  6  1  1  3  6  0  7  2  1  2  0  5  7  0  6  5  1  1  3  0  1  7  0  5  6  1  0
 0  0  0  1  0  1  0  3  5  5  4  3  4  2  4  2  2  1  1  1  4  0  7  7  3  6  3  6  7  1  1  1  0  4  4  6  6  1  7  2  1  2  7  7  5  6  5  1  7  5  1  4  2  0  0  2  1  7  1  1  0  2  7  1  4  0  3  1  5  6  4  2  3  1  3  4  5  6  5  0
 0  0  0  0  1  1  5  5  0  1  5  6  0  3  4  1  3  7  2  4  5  6  1  6  1  2  0  7  5  7  2  7  2  3  7  7  0  2  0  7  1  3  4  5  0  7  0  1  1  4  7  6  6  3  4  2  1  3  7  4  6  7  0  2  5  6  4  7  3  4  1  4  4  4  2  2  5  1  5  2
 0  0  0  0  0  2  2  2  2  2  2  4  2  0  2  4  2  0  2  4  0  0  2  2  4  2  2  2  2  0  0  4  6  6  4  4  0  4  6  0  2  4  4  6  2  6  4  6  4  6  4  4  4  4  6  0  0  0  0  4  2  0  0  6  2  6  2  2  4  0  4  6  0  4  4  0  6  2  6  4

generates a code of length 80 over Z8 who´s minimum homogenous weight is 68.

Homogenous weight enumerator: w(x)=1x^0+162x^68+528x^69+1181x^70+1790x^71+2843x^72+3628x^73+5051x^74+6182x^75+7914x^76+8772x^77+10543x^78+10584x^79+11759x^80+10850x^81+11161x^82+9218x^83+8086x^84+6498x^85+4994x^86+3364x^87+2521x^88+1422x^89+986x^90+436x^91+252x^92+154x^93+90x^94+38x^95+24x^96+20x^97+10x^98+4x^99+6x^100

The gray image is a code over GF(2) with n=320, k=17 and d=136.
This code was found by Heurico 1.11 in 288 seconds.