The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  2  2  2  2  2  2  2  2  2  2  2  1  2  2  1  2  1  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  1  1  1  2
 0  4  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  0  0  0  0  0  0  0  0  4  4  4  0  4  0  4  4  0  4  0  0  4  4  0  4  4  0  4  4  0  4  4  0  4  4  0  0  0  4
 0  0  4  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  4  0  4  4  0  0  4  4  4  4  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  0  4  4  0  0  0  0  4  0  4  4  4  0  0  0  4  0  4  4  0  0  0  0  0  0  4  4
 0  0  0  4  0  0  0  4  4  4  4  4  0  4  4  0  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  0  0  4  4  4  4  0  0  0  0  4  0  4  4  4  4  4  0  0  0  0  4  4  4  0  4  0  0  0  4  4  4  4  0  0  0  4  4
 0  0  0  0  4  0  4  4  4  0  0  0  0  4  4  4  4  0  0  0  4  4  4  4  4  4  0  0  0  0  4  4  0  4  4  0  0  4  4  0  0  4  4  0  0  0  0  4  4  0  4  4  0  0  4  0  0  0  4  4  0  4  4  4  0  4  0  4  0  0
 0  0  0  0  0  4  4  0  4  4  0  4  4  4  0  0  4  0  4  4  4  0  0  4  0  4  4  0  0  4  4  0  4  4  0  0  0  0  4  4  0  0  4  0  4  4  4  4  4  0  0  0  4  0  4  0  4  4  4  4  0  0  0  4  4  0  4  4  0  0

generates a code of length 70 over Z8 who´s minimum homogenous weight is 68.

Homogenous weight enumerator: w(x)=1x^0+53x^68+158x^70+35x^72+7x^76+2x^102

The gray image is a code over GF(2) with n=280, k=8 and d=136.
This code was found by Heurico 1.16 in 3.06 seconds.